My Chemical-Free House

A Guide to Creating a Healthy Home

Tiny Homes and Trailers

How to Offgas a New Car

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This post contains affiliate links. Upon purchase, I earn a small commission, at no extra cost to you.

This post will go through the techniques used to help promote offgassing of the VOCs in a new car. That “new car smell” is made up of VOCs and we can speed up their release or mitigate them with a number of hacks.

Not all toxins in new vehicles are gasses (VOCs) however. We will also look at avoiding, cleaning and sealing nonvolatile toxins like metals and flame retardants.

1. Pick a Less Toxic Car

Makes and Models

The most recent study that compares the toxicity of vehicles across brands was in 2012. The study revealed the top picks to be the Honda Civic, Toyota Prius, and Honda CR-Z.

The worst of the bunch were Mitsubishi Outlander Sport, Chrysler 200, and Kia Soul. Though things could have changed with these brands since 2012.

Toxins of Concern

The most worrisome toxins are metals, flame retardants, and PVC followed by VOCs. A number of cars are now free of PVC and some have cut out brominated flame retardants (though replaced with flame retardants that are just as worrisome).

Some models contain more metals than others. Metals and flame retardants are not VOCs and they have no odor. They also do not dissipate the way VOCs do. Flame retardants will continue to come out of the foam for the lifetime of the foam. Metals also are rubbed off or released over time.

Honda is still popular amongst those sensitive to chemicals. The company puts out an environmental report every year which shows that most Honda and Acura models are PVC-free and they use low-VOC adhesives, tapes, foams and coating materials inside the vehicles (source).

Ford has also made a big effort recently to reduce offgassing.

See them in Person

If you are sensitive to offgassing you will likely want to look at a few different makes and models in person to see how you feel in them. A 2007 study showed that interior VOC emissions varied greatly between makes models and trims and even within the same make/model/trim. (Source)

Partially Offgassed

You may also want to consider a car that has been on the lot for longer, and may have partially offgassed already.

Certifications

There isn’t a universal or widespread certification for indoor toxicity of vehicles.

TUV Toxproof certifies levels of interior vehicle toxins including heavy metals. They have not released publically what levels they are allowing. And without being able to compare that to vehicles that have not applied for this certification, it makes it hard to make much use of it. Brands that are certified include Mercedes, Volvo, Renault, Land Rover, and Jaguar.

I think this is a good idea and I look forward to having a certification like this become more transparent and more widespread.

Some fabrics in interior cars are certified by Oko-Tex Standard 100. Volvo has this certification. However, the fabric is not my biggest concern in the vehicle.

How long does a new car take to offgas?

In terms of the chemicals that are volatile, and produce that new car offgassing odor, this study found a lot of variability between brands. However, after one year the VOCs were down to 1/10th the original level.

The offgassing of VOCs is not a linear process, it’s on an exponential curve. There is a sevenfold decrease in the first month of use, or about 20% per week (source). To facilitate offgassing there needs to be air movement (and heat help a lot too).

2. Heat it and Air it Out

Heat and Air while Parked

Heat, air and time are certainly the main ways to offgas a vehicle. You can heat it by putting it in the sun, by running the heating system or even with space heaters (very carefully in a small space).

When you are heating materials you are releasing the VOCs and also creating new VOCs (this study explains), so make sure when you are heating up the new vehicle you are airing it out substantially at the same time so that the gasses have somewhere to go.

Windows should be open while you are heating the vehicle. Windows can also be left open anytime it’s safe to do so.

When it’s raining or otherwise unsafe to leave the windows down, I would reduce the temperature by using window sunscreens because the VOCs being released have nowhere to go.

Aim for a substantial amount of airing out with heat in the first 6 months.

Temperature Control and Air while Driving

When you are driving you will want to keep the HVAC on fresh air intake which reduces VOCs by diluting the air, or open the windows.

While you are driving, lower the temperature to reduce the release of VOCs inside the vehicle.

3. Deep Clean your Vehicle

Deep Clean the Seats

If you have cloth seats I would have the seats cleaned with a shampoo extraction. Or possibly steam cleaned.

AFM Safecoat makes a carpet shampoo that can be used for this purpose in lieu of the more toxic products that car detailers use.

You want to use an extractor that pulls some of the chemical coatings off the fabric as well as toxins that got absorbed by the fabric when the car was brand new. You can use that on carpet floors as well.

Make sure the upholstery can dry out quickly and thoroughly to prevent mold growth. My post on preventing mold in cars goes into more detail.

HEPA Vacuum

To capture flame retardants (FR) you want to use a HEPA vacuum (add the HEPA filter and bags) as often as is reasonable for you. FR are constantly coming out of the foam for the lifetime of the product. They are not gasses.

Wipe Down Surfaces

Phthalates and metals are another chemicals that live in dust. Wiping down all hard surfaces alongside vacuuming is a good way to mop up these chemicals.

While other websites recommend microfibers clothes because they are particularly good at grabbing on to dust where many of these chemicals live.

I would also be concerned with bringing those back into the house carrying heavy metals, phthalates, and flame retardants, and I therefore might opt for more disposable clothes, like these ones.

Although it might seem excessive to some, when cleaning up dust that contains heavy metals and flame retardants, I would wear an N95 mask. These toxins are much harder for the body to process and much more fundamental in terms of the cause of illnesses.

You can use a gentle cleaner like AFM Super Clean or any gentle soap that you do well with. Here is my list of cleaning products.

Clean up Oil Residue

If there is excessive oil residue left on any car parts, you can clean that up with TSP mixed in water. Be careful not to remove lubricants that are needed for the functioning of all the door parts (and other parts of the vehicle).

3. Use Absorption Materials

There are a number of materials that absorb VOCs that can be placed around the vehicle. These are especially useful when the vehicle has to be closed up due to rain, humidity or for security reasons.

Carbon/Charcoal. My go-to would be carbon/charcoal because it’s relatively cheap and it is effective. These pellets from Amazon are the least expensive charcoal to use. You can get them at Walmart as well.

Zeolite and Minerals. You can also use bags of zeolite, and the EnvironKlenze odor eliminating pads, which are made of minerals.

Baking Soda or Vinegar. Some articles have suggested putting out bowels or trays of baking soda or vinegar. Those can help. If you have them handy you can put them out for 24 hours and discard them when they are saturated. But they are not as effective as the charcoal.

Absorptive Powder for Seats. You can use the same strategy to absorb VOCs coming out of seats. You can sprinkle baking soda or zeolite powder on the seats, let it sit for 12 hours and then vacuum it up. The challenge with this strategy is that the particles can get stuck in some fabrics.

Air Purifier with Carbon. While you are storing the vehicle you can also run a full-sized high carbon air purifier. Run it on an extension cord. Here is my list of the best air purifiers for high offgassing. Austin Air is my top pick.

4. Use Sealants to Block Toxins

A less common strategy in a vehicle is to use sealants. In general, you want to offgas anything with heat and air first. As sealing will by definition slow down the offgassing, meaning it actually goes on for longer.

In a car that you cannot heat and air out for any reason, this strategy can be used.

Seal the Fabric Seats. AFM makes a product for sealing in offgassing in carpet which can also be used on car seat fabric. The product AFM Lock Out is spray applied to the seats.

Seal Vinyl. AFM also makes a product called Hard Seal which can be used to seal hard vinyl components. Use three thin coats applied with a sponge. So many new make and models are vinyl free so unless you must go with one that has vinyl, I would look at those other options. I would also be sure of what the material is before going ahead to seal it.

Seal other Plastics. AFM Acrilacq can be used to seal plastic in some vehicles (and is used in Hyundai to seal in some of their plastics). Talk to Green Design Center if you are not sure which product would work best.

The idea to seal surfaces in a car came from Non Toxic Environments Podcast.

If the plastic components contain heavy metals, which they do according to the Ecology Center report, I would use this sealing strategy.

Use Seat Covers. Plastic seat covers will block flame retardants and metals in the seals.

5. Use Air Purifiers/Filters

There are small air purifiers made for cars but you can also put a full-sized air purifier in the back seat. I will go through both options.

Air Purifiers Made for the Car

Many companies that make air purifiers make a smaller model for vehicles. These plug into the cigarette lighter:

  1. EL Foust car air purifier has a 60 CFM fan and 3 lbs of carbon. The CFM (the amount of air it’s cycling through it) is good for a car.
  2. Air Oasis Mobile Unit uses PCO and generates ions. They claim the mobile unit does not give off any ozone. The fan size is not important as this machine puts out ions. The post on PCO explains in more detail.
  3. IQ Air Atem Car 18 CFM, less than 1 lb of carbon.
  4. Other popular models are similar, the Aireox Automobile model has 75 CFM fan and 2.5 lbs carbon.
  5. The Amaircare Roomaid is 32 CFM with only half a pound of carbon.

Using a full-sized Air Purifier in a Vehicle

I mentioned above that you can use a full-sized air purifier on an extension cord while the vehicle is parked. But you can also use a full-sized air purifier like Austin Air while driving.

These inverters can run an appliance up to 300 watts. Air purifiers are usually around 150 watts. You can put an Austin Air, or another air purifier on this list, on the front seat or backseat. Just make sure it’s secured down really well so it is not a flying missile in a car crash. Use the inverter to run it off the cigarette lighter.

You can buy Austin Air through Amazon, Air purifiers of America, and Walmart.

The HEPA component can be useful for capturing flame retardants and particulates, but it’s the carbon (or other sorbent materials like potassium permanganate or zeolite) that is going to make the difference in terms of reducing VOCs.

If you are incredibly sensitive, a full-sized air purifier is the way to go.

6. Should you use Ozone to Offgas a Car?

I would not personally use ozone to reduce the offgassing of a new vehicle.

Ozone works well on specific odors – smoke and fragrance residue most notably. It helps to kill and denature mold. And I did find it useful in offgassing the new glue smell of metal trailers.

But ozone interacts with many VOCs to create some unknowns. Especially in a car where the mix of VOCs can change from vehicle to vehicle, new VOCs that we can’t predict can be created.

It also leaves behind oxidation of materials, which smells horrible and can worsen things.

I have heard from folks who have had success using ozone to offgas new cars. If that works for you, carry on. But for folks new to using ozone for VOCs, I would discourage that experiment. See my post on ozone for precautions.

Myths about Offgassing Cars

Masking odors – Other websites are promoting odor masking agents to get rid of that new car smell. Please don’t add more toxic chemicals to cover up toxic chemicals.

Using the car’s cabin filter – This gets mentioned a lot too. The cabin air filter is mainly to protect the HVAC system and keep dust out.

You can add a filter with charcoal or even a HEPA filter. This minimal amount of carbon is not going to make a dent in the offgassing, and would only help when it’s on recirculate.

When you are driving the vehicle during the initial offgassing phase you want to keep outdoor air coming in as much as possible, not on recirculate.

Though it’s still a good way to help keep your HVAC system clean and keep some particulates out if you have high air pollution outside.

For those sensitive to outdoor pollutants, I would use a HEPA cabin filter. This can be especially useful if interior offgassing is forcing you to keep the air on fresh air intake and you are sensitive to outdoor pollution.

Corinne Segura is a Building Biologist with 6 years of experience helping others create healthy homes.

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Designed for Mold-Prevention – Corbett’s Tiny House

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building a high performance mold preventative tiny house

This post contains affiliate links. Upon purchase, I earn a small commission at no extra cost to you.

Intro

Corbett and Grace Lunsford’s tiny house on wheels (THOW), called the Tinylab, was made as an educational house to teach folks about home performance.

In this article, I’m going to outline the areas of this tiny house’s home performance that are relevant to mold prevention.

These mold preventative aspects of the house are:

  • Air sealing to prevent vapor from entering the cavities of the enclosure.
  • Using vapor retarders wisely, to prevent condensation in walls and the roof.
  • Insulation installed without significant air leakage (air leakage = vapor movement = condensation potential).
  • Windows flashed and taped correctly to prevent water infiltration.
  • Using ventilation to reduce humidity, and avoid negative or positive pressure which can push or pull air through the walls and cause consequences.

I also outline some other facets of the house that make it a healthy home. These are:

  • Low VOC materials
  • Improving indoor air quality by reducing carbon dioxide, carbon monoxide and VOCs
  • Controlling humidity
  • Managing microbial growth in tanks
  • Energy/Power system which provides for flexibility of location

I haven’t seen many tiny homes on wheels built really well. This is only the second one after Terran’s house that I have featured as a mold preventative build.

Air Sealing is Key

In Corbett’s High Performance house, air sealing is incredibly important. Air sealing is how you prevent air from entering the wall and other cavities. This is important because air carries vapor, and it’s usually at a different temperature.

Air leakage brings with it vapor that can condense on hidden surfaces.

This build used materials that are made for Passive House design. Passive House is a design process that includes a major focus on controlling for moisture and condensation within the walls, ceiling, and foundation.

The Exterior Water Resistant Barrier (WRB)

Solitex Mento membrane and tapes were used, just like in this detailed example.

Solitex Mento is a breathable house wrap/WRB that comes with a line of high-quality tapes for sealing around all seams and openings.

Most houses should have a breathable exterior water-resistant barrier over the sheathing, with a vented rainscreen system. A rainscreen is battens that create a gap behind the siding. This lets moisture escape and dry out.

These products are good at air sealing and they are also lower VOC than liquid applied barriers. Many high-quality builders are now using liquid applied barriers in many areas of the house, and that might not work for all chemically sensitive folks.

Interior Vapor Retarder

Inside, the Intello brand smart vapor retarder was used to prevent moisture from entering the cavity in the winter and let it breathe more in the summer, preventing condensation within the wall cavity.

We want to get away from using vapor barriers that trap moisture. Instead, these two permeable membranes, one on the outside of the wall and one on the inside, control air flow, and slow vapor flow but don’t stop it completely.

The Insulation

With Rockwool R 15 in walls and ceiling, the Tinylab house can be moved around the US to multiple climates. You always want to design the house with one climate in mind to optimize all the systems (and the whole house as one system).

This house was built for Atlanta. As they moved the country they had the most difficulty with humidity and condensation in very humid and very cold climates. They attempted to follow the weather to reduce this challenge before returning to Atlanta.

Rockwool is easier to pressure fit into cavities compared to cotton batt. They tried the recycled blue jean insulation at first, but it was sagging in the ceiling, and leaving a little bit of air gap in the wall cavities. You can see that here.

Rockwool holds itself in well with a friction fit in both the ceiling and the walls, without sagging and leaving air gaps. The tighter it is to the framing the better.

If your insulation is not tight to the framing air leakage can lead to moist air moving through the wall and condensating. A lot more moisture moves into the wall with air leakage than with diffusion. Diffusion itself moves very little moisture, not enough to cause problems in a well-designed wall. Matt Risinger explains that in this video.

You need to take your time to cut and fit the insulation as perfectly as possible so that you don’t have air leakage.

They didn’t use spray foam, even though folks like the idea of insulation that in theory is an air sealant and a high R-value insulation product in one.

In reality, spray foam often pulls away from the walls, in which case you lose the air seal. And in a tiny house on wheels that is moved around, it’s going to crack and come apart from the studs almost for sure. Bad idea.

Here is the interior air barrier and air sealing:

Low-VOC Materials

There was a big focus on 0 and low-VOC materials throughout the whole build which I appreciate seeing, even though the Lunsford family is not chemically sensitive.

Walls and Cabinets

Purebond plywood which is made with a “soy glue” (probably a polyurethane glue) was used for the interior walls and cabinets as well as the interior door.

If you are sensitive you should test this out for yourself. I prefer plywood made with phenol-formaldehyde which has a defined short period of offgassing before it cures, compared to an unknown glue and VOC that we know less about.

For the walls here I would have preferred just a solid tongue and groove wood. With plywood only used for cabinets.

Flooring

The floor is APC Cork, which looks awesome and is great for sound dampening. For most moderately to severe chemically sensitive folks, cork flooring is too high in polyurethane glue (and VOCs).

There are many similar floors you could put down in a tiny house that are extremely low (lower than this) in offgassing. I list them here in my flooring post.

Insulation

Both Rockwool and EPS (polystyrene) foam insulation are used in the house. Both healthy choices. Rockwool is my go-to insulation to consider before moving on to more unusual options.

My insulation post goes more in-depth into insulation choices and why rigid foam is still a good choice for most sensitive folks.

Rigid foams are frequently used as exterior insulation (outside of the framing) as part of the system design to prevent thermal bridging and to help prevent condensation.

This video has some good information on the insulation:

The Devil is in the Details (Like Window Flashing)

When designing and building a mold preventative house, the devil is always in the details. Flashing is an area that is more often than not done wrong on new builds (along with the air sealing layers like the house wrap).

I liked this detailed video below on how to properly install a new window to prevent future moisture issues.

Maybe this looks simple and like anyone who can follow instructions can do it, yet almost every builder makes mistakes here.

It’s rare that I see a build in progress with the house wrap/WRB and all flashing done right. You should supervise this part of any build.

When windows and other openings in the exterior are not detailed right, water that gets behind the siding finds its way to the plywood or OSB sheathing. Enough moisture will cause water damage and mold here. As damage continues it will get into the framing and wall.

In regular builds, other openings in the wall for vents or wiring are often left without any sealing (flashing)! Big problem for water and air getting in.

Water is expected to sometimes get behind the siding – that’s not a fatal situation. It’s supposed to be able to drain, dry to the top and bottom, and stay out of the walls.

The windows are Pella brand wood windows with aluminum cladding on the exterior. The caulking recommended for this combination of materials is DAP 3.0 Window, Door, Trim & Siding High Performance Sealant.

Here are the WRB instructions from 475 if you prefer diagrams to video. All the brands come with detailed instructions, there is no excuse for a builder to not know how to do this.

Exhaust and Ventilation

What Happens if you only have Exhaust Fans

The object in the Tinylab is to have active balanced and controlled ventilation.

It’s easy in a tiny house to create negative pressure with a high CFM (CFM is the amount of air it’s moving) bath fan or range hood. This pulls way too much air out for such a small space. This can happen in any well-built air-sealed house, but it’s exaggerated in a small space.

The problem with that is that you start to pull in air back through any gap that the air can find a path through. And back through places you don’t want to pull through – like exhaust vents or even the composting toilet in this case! You might also be pulling in moist outside air.

You aren’t getting healthy make-up air this way (which is the air that’s coming in to make up for that exhausted air).

Why you want Air Moving In and Out

Without enough air exchange (air coming in and going out) in a small space, you can also raise your carbon dioxide.

Having air exchange (meaning you replace the indoor air with fresh outside air in a controlled way) is the best way to reduce carbon dioxide, VOCs and other pollutants, like those produced by a gas stove.

This house has a number of high tech ways to manage the air quality and replace the air.

An Energy Recovery Ventilator

A Broan HRV (later switched out to an ERV) exchanges indoor and outdoor air in a balanced manner. The ERV is working better for them in their climate because it buffers both humidity and temperature.

You need to look at the house as a system and your climate to determine which one you need.

The negative air (exhaust) side of the ERV is venting out of the bathroom, and the positive air (incoming air) is coming in over and under the loft.

The fresh air comes into the loft area with a damper to control whether it goes down to the sleeping area below.

This video explains what an ERV and HRV do and what the difference is.

Exhausts and Make-up Air

The composting toilet and kitty litter box area has a 3 CFM exhaust vent to keep that air moving out (a very small fan, just enough to keep it moving out).

The gas stove has an exhaust fan venting out over it, to pull out moisture, carbon monoxide and other pollutants and particulates from cooking. When this fan kicks on, it opens up a damper that brings in fresh air right under the stove. This keeps air circulating and moving out right where you want it to.

You can see it in action here:

Monitoring the House

The house has a number of cool monitors that help you know that everything is functioning as it should be.

Carbon Monoxide

Defender brand low-level Carbon Monoxide monitors detect low levels of carbon monoxide. This is important if you are running appliances on fuel. Your carbon monoxide level should be 0 in a healthy home.

Elderly, children and those with compromised health are more affected by low levels of carbon monoxide. The cheap monitors are only going to show you when the level is already too high.

Radon

Corbett has a radon monitor from Trutech tools, which is useful in a regular house. Though here it is used for teaching purposes. If you are not on a foundation you don’t need a radon monitor. (Though if you have a granite countertop this might be interesting to see!)

Corbett is aiming for 0 radon in all his houses.

C02 & VOCs

The Foobot monitor tests for carbon dioxide (what you breathe out, this will show you if you have enough fresh air), VOCs, particulates, temperature, and humidity.

Pressure

Retrotec manometer measures the pressure inside, making sure it’s where you want it to be. In the Tinylab they are making sure it’s more or less equalized.

It also monitors the pressure of the incoming air through the ERV. Just an extra data point to show Corbett that everything is functioning, and for educational purposes. For most people, this extra step would not be needed.

Though it would be interesting to see the pressure in the house as a whole. Just seeing that would tell you if something is wrong with one of your fans or exhausts.

Temperature

Two Dwyer temperature gauges measure the temperature of the incoming air through the ERV, and the air inside the wall on the backside of the insulation. These show how well the house is managing the temperature.

The temperature gauge on the inside of the sheathing can help you to calculate if there is a risk of condensation on the sheathing or exterior vapor barrier (if you have an exterior vapor barrier). Especially if that is coupled with air leakage (which you can use an infrared camera to check for).

A third gauge wraps around a plumbing pipe under the stove to see if there is a chance that pipe will freeze. Smart!

Mechanicals / Systems

Greywater & Blackwater

The greywater tank is on the exterior and is portable and on wheels. I like this idea as you don’t have and scum build-up inside hidden tanks. And not having a blackwater tank definitely cuts down on the kinds of bacteria and mold you might be fermenting in your tanks. (They use a composting Air Head toilet instead).

Freshwater

The freshwater tank, stored inside under the sink, won’t freeze. It uses chlorine to keep it bacteria and fungi-free, it’s not for drinking unless you want to filter the chlorine out.

In the last section, you can see the major leak they had with this tank and how they put more precautions in place after that.

Fuel & Electrical Systems

They have three solar panels that are portable, on a long cord and are set up on the ground. They can be moved around to maximize sun exposure. It’s not a great idea to put panels on the roof; more holes = more chance of leaks there.

You can also plug the house in; the whole house runs on one extension cord that runs off a regular house outlet (15 amps). That is an impressive (low) amount of power usage. It gives you the ability to be super flexible with where you live. Either going off of solar and propane, or one plug into any house.

The stove and hot water heater run on propane, which cuts down on electrical usage.

The Mitsubishi mini-split only needs to produce 5000 BTU of heat, 4000 BTU of cooling to keep this house warm and cool enough for their climate. It runs off only 200-300 watts.

This is something you need to calculate in at the design stage. You don’t want an oversized or undersized system.

Mini Split heat pumps are ductless systems, they do not bring air in or out of the house.

This does a little bit of dehumidifying, and in some conditions, the ERV helps too. But they also found they had to add this desiccant dehumidifier.

This video shows the mechanical systems and is a good overall tour:

Design of Walls, Ceiling, and Floor

Floor Design

The base of the house was designed to use the trailer cavity as an insulation cavity. EPS foam with foil backing was placed in between the metal trailer joists.

Underneath the whole trailer, there is a metal barrier to prevent water from splashing up. There is no thermal break underneath the metal trailer framing. This is a typical design for tiny homes on wheels.

On top of the framing, plywood is placed against the metal. It looks like there might be a slight gap between the EPS and the wood.

I wouldn’t recommend this design of the floor system in terms of preventing condensation and mold.

In fact, the flooring system is where you should put the most thought and planning. Bring in an architect like Cheryl Ceicko, or Passive House designer like Mike Maines.

It’s easy and common to have condensation in the flooring of a tiny house on wheels. The metal trailers make this difficult. There is a lot of thermal bridging. You need to decide between thermally breaking this underneath with foam or building up a breathable system on top.

Those who have designed with mold prevention as the main goal have all built up on top of the trailer. This post shows a detailed example.

EPS is also used around the metal wheel wells, a place that is prone to condensation.

Roof/Ceiling

The roof has plywood decking with foam exterior insulation on top (1 inch EPS), then Solitex Mento, then a rainscreen, then 26 gauge metal roofing.

Walls

The walls are regular 2 x 4 framing with Rockwool, plywood sheathing, a rainscreen, and is breathable to both sides with the Solitex and Intello products.

Make sure your rainscreen is vented, it’s a tricky detail in tiny houses on wheels.

What went Wrong?

A Flood

The Freshwater bladder did leak and it was quite the flood. After that, the Lunsfords put some precautionary measures in place.

Anyone preventing mold would want to do this from the start, making sure a leak-prone area is a waterproof protected area and you have these leak alarms.

Mattress on the Floor!

The foam mattress was put right on the floor. Always a no-no! This causes mold underneath. They changed over to an air mattress which does not let moisture transfer through it.

Condensation in Storage

They also had condensation on the wall in the backside (at the back of the drawers that were full of clothes and things) on the really cold days. That’s a place to keep an eye on. You may even want to design your storage a little differently in a cold climate.

Realistic Expectations

Corbett doesn’t have unrealistic expectations on how long a tiny house will last. He says no more than 30 years.

They put a lot of miles on the house but it was designed with an engineer to make sure that it would hold up to those forces. In that sense, it was designed well for the motion.

Building a tiny house when you have sensitivities is in a way a trickier endeavor. You are in a much smaller air space with all the items that offgas that you can’t avoid – appliances, flooring, caulking, glues, windows, doors.

You are also in a much smaller space with EMFs and you cannot get away from that.

In the end, I still like tiny houses for those with mold and chemical sensitivities, but only if you know full well what you are going into and have taken the time to design a detailed mold preventative build.

There’s a lot of work involved here – you are designing a full system. Just about as complicated as a regular-sized house.

The only part that is easier due to the size is that you have an easier time supervising the build. The HVAC is also less complicated.

I am currently taking Corbett’s course in Home Performance to become certified with the BPI as a Building Analyst. Corbett consults on home performance, and you can contact him here.

Corinne Segura is a Building Biologist with 6 years of experience helping others create healthy homes.

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Prevent & Decon Mold in Your Car & AC

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prevent and treat mold in vehicles

This post contains affiliate links, upon purchase I earn a small commission at no extra cost to you.

This article covers the sources of mold growth in vehicles – AC system, high humidity storage, spills, leaks, and design malfunctions – and how to prevent them.

I go into detail on the four methods used to clean the HVAC system out, as well as methods to clean mold and cross-contamination in the vehicle as a whole.

The AC is usually the most difficult area in the vehicle to manage microbial growth. While there are certain makes and models of vehicles where this is more of an issue, to some degree it’s a problem in all vehicles due to the inherent design of the AC system.

Preventing Mold in Vehicles

Preventing Mold in the AC and Heating System (HVAC)

prevent mold in the car's AC system

The fungi and bacteria grow mostly in the evaporator core and immediate surrounds, due to humidity and moisture that forms when AC is in use. Mold can form in the ductwork as well.

To help reduce mold formation in the AC system, run the fan for the last 10 min after using the AC. (Defrost is also AC, so you need to run the fan for 10 minutes after defrost as well). This helps the evaporator dry out.

Using recirculate can worsen the problem in some situations. Bringing in fresh air (if the outdoor air has drier absolute humidity) as opposed to using recirculate can help the evaporator to dry out.

Another thing you can do is to avoid parking in areas where a lot of debris can enter the air intake.

Similarly, when driving through very dusty areas, you are bringing in dust and spores through the air intake. You may want to turn off the HVAC system completely in those conditions.

Maintenence on the vehicle should include changing the cabin air filter as needed (when it’s dirty).

I would include one of the four HVAC cleaning methods below as a preventative (before you start smelling or reacting to mold) if you do use the AC system regularly.

For those Extremely Sensitive to Mold in HVAC – How do you Turn off the AC?

Many folks who are extremely sensitive to mold do not use the AC system in their vehicle at all. If you refrain from using this right from the start with a new car, you will avoid most of the problems here.

If you want to avoid AC use altogether, using just the heating system should be fine. But, keep in mind many new vehicle models have automatic climate control which will use both heating and cooling under many different conditions (not just when defrosting). If you want to turn off the AC, look for a vehicle where this can be done – new cars have a way to disconnect the AC compressor. Ask a mechanic how to do this.

Does the auto setting on cars use AC and how to turn off AC

If you have already used the vehicle’s AC or you bought a used vehicle that has some funk in the HVAC system, then even the heating setting will circulate the fungi and bacteria throughout the vehicle.

Buying a vehicle with heated seats is a good idea in case you become sensitized to the vented HVAC and need to turn it off for a while (and try and clean it). Some very sensitive folks have had to turn it off permanently if they have not had success with the cleaning methods.

One other hack is that you can externally mount the HVAC system to get easy access to the evaporator. This is a very unusual hack. You can find photos of it in the group Mold Avoiders on the Road.

Alternative Ways to Stay Cool in the Car

Cars that Come with Cooling Seats

Some of these built-in systems blow unrefrigerated air through the cushions. And some use refrigerated air that is tied into the main AC systems. The unrefrigerated air system may be safe in terms of mold prevention.

Safer Cooling Seats (or Heating)

You can also add your own cooling and heating seats to avoid the use of your car’s HVAC system.

Cooling seats that you add yourself work simply by adding a fan that blows unconditioned air which helps to cool you down.

This one (pictured) that uses fans is affordable.

The heated seats use coils, just like a heated blanket or heated jacket. Some models like the Naipo do both.

Then there are gel seats, I like the idea of the ones you put in the freezer first, then you bring it out to the car with you. This is a kids version. If you know an adult version let me know, I think it’s a good idea. You will want to dry those off though, when they come out of the freezer they are probably going to condensate.

Cooling Vests

When I used to have severe heat intolerance, I used cooling vests on my body – both active and passive vests work.

The active vests provide more cooling but are more expensive.

They were life-saving for me until I healed from heat intolerance.

Preventing Mold in the Car (as a Whole)

does mold grow in cars just from sitting in humid climates
Many of us stored our vehicles in the humid winters of the Pacific Northwest, to come back to moldy cars

Why Mold Grows Inside Vehicles

There are a few ways your vehicle can become moldy inside on the seats and upholstery. Sometimes just leaving a car to sit in a very humid place for long periods of time can cause mold to start growing on the seats.

More common though, is a spill or window left open that wasn’t dealt with fast enough.

Other sources of water damage are less common:

  • Debris accumulating in the air intake areas and connected drains (keep your air intake area clean, and change the filter). The cowl intake and drain area can collect debris. Those areas are connected to body cavities that can harbor microbial growth. Thus structural mold is possible in a vehicle, though this is less likely than mold growth in the HVAC and inside the vehicle.
  • Rainwater that has gotten into the HVAC ducts and car interior in some past Ford models – causing hidden pooling of water.

Ways to Prevent Mold Growth in Vehicles

Prevention here is key. Once mold is actively growing and has made it through to the foam in the seats, it’s a huge problem that is hard to fix.

When storing your vehicle for long periods of time in a constantly humid climate, it’s best to leave it in a sunny spot and leave it with a dehumidifier. Climate controlled indoor storage is of course ideal.

Though generally, a vehicle should be able to withstand a good amount of humidity while being stored, really high humidity for long periods has been a problem for me. I left a truck in 70-95% humidity for a couple of months and came back to mold growth. No known water intrusion.

Many others in the Pacific North West and similar climates have left vehicles sitting to come back to visible mold growing (and not from leaks).

Both active (battery-powered), and passive dehumidifiers will help. You can also monitor the outdoor humidity.

I would check on the vehicle (or have someone check on it), both to empty the dehumidifiers and possibly to dry the vehicle out actively with heat and airing every few days if necessary.

When you spill something or leave the window open, just do everything you can to dry it out within a day, which includes the above: usually sun and air, or heat and air. Add dehumidification only if it’s going too slowly.

Decon/Clean Mold or Cross-Contamination in a Car

DISCLAIMER: Some of the cleaning methods discussed in this article, that include ozone, chlorine dioxide, hydrogen peroxide, and quaternary ammonia, require knowledge of safety precautions for handling the materials, and executing these methods. Please take full responsibility for your health and wellbeing and make sure you understand the risks, precautions, and procedures – not all of which are explained here in full (please research them before proceeding or consult with an expert). Full disclaimer here.

use a HEPA vacuum to decon mold in a car

If you do have some light surface mold in the car or cross-contamination, I would start with a deep clean.

If you had a big spill that didn’t dry out, or you suspect someone else did in your vehicle, you might want to open the seat covers to check on the foam. Some have zippers. If they don’t you would have to cut them open to check.

Mold in the foam cannot be properly remediated other than with replacement.

Deep Clean your Vehicle

You can remove light surface mold or cross-contamination by steam cleaning or shampooing the seats.

Make sure it is dried out quickly after that. Car detailing shops can do this. Just make sure you know which products they are using, as some might not be acceptable, toxin-wise.

A mechanic I talked to near Vancouver BC, does a shampoo of the seats with high temp extraction, then an enzyme spray on the seats instead of ozone to reduce odors. I use similar enzymes to break down odors.

DIY HEPA Sandwich for a Car

If it’s not so bad as to warrant a steam clean or extractor shampoo, use a HEPA vacuum, which you can do your self. Vacuum the seats and carpet, and upholstery.

For a vehicle, you want a rather flexible hose. I would use the Shop-Vac. I’ve used this one before with the HEPA filter and HEPA filter bags.

You can then wipe down all surfaces with quats or the cleaning product of your choice. A proper HEPA sandwich would involve another round of vacuuming.

Having your car or truck professionally detailed can help, as they do a very thorough clean, though I haven’t seen them do HEPA vacuuming.

Using Ozone on Cross Contamination

I use this little one from Amazon

If those methods don’t cut it, and you are still sensing mold in the vehicle, you will want to use the methods below.

Many people do use ozone and it does work, but it leaves behind oxidation, which smells quite terrible.

Depending on how long you ozonated it for, it can take a while to die down.

I don’t agree that you will damage the wiring easily, you would have to use extremely high levels for a very long time to do damage like that. Many mold avoiders have ozonated vehicles at very high concentrations for 24 hours, many times. I have done a couple 24-hour treatments on my truck.

Car dealerships use this all the time as well (but normally in much shorter treatments, like 1 hour). Many people only do 2-hour treatments for mold, which should not cause damage to the plastics, and would only cause minimal oxidation odor after.

There is more info below on pumping ozone through the HVAC. If you don’t need to pump it through the HVAC, just see my general post on ozone and run it inside the vehicle. I use the little Airthereal.

Please read through the precautions thoroughly, since ozone is a dangerous gas that can be deadly.

Another oxidization method, though it is a weaker oxidizer than ozone, is to use chlorine dioxide gas. That method is explained below, in its own section.

Other Fogging Methods for Mold

If you have another decon method that has worked well for you in decontaminating your house from mold, it’s likely you can use that here – like thieves oil fogging, Concrobium fogging, or using quats.

Silver Hydrogen Peroxide though, is likely too much oxidation for most vehicles, though it can be used in the empty part of metal cargo vans.

Chlorine Dioxide Gas to Treat Mold

Chlorine Dioxide, like ozone is an oxidizer. Like ozone, there is evidence that it breaks down mold and mycotoxins.

Although it’s weaker than ozone, you should take the same safety precautions outlined here. It is dangerous to breathe in and it’s explosive in certain concentrations.

You may not need to be so far away from it like with high doses of ozone, which is an upside. It’s also cheaper and easier.

Keep it simple and buy the ready-made tablets or packets on Amazon. They are inexpensive and work just as well as mixing it yourself. NosGuard is one brand, Reset is another one.

Read the safety instructions carefully on the product and make sure you understand them. Never use a chlorine dioxide product in occupied spaces.

If you want to make it yourself, please take full responsibility for your safety and wellbeing. Here are the instructions:

How to make chlorine dioxide gas treatment for the home or car: 6.5 oz (roughly 3/4 cup) Oxine plus 3-4 tsp citric acid in glass or heavy plastic container, one for each room. Leave it for 3 hours for a shock treatment or 24 hours for a deep treatment.

You can make a smaller batch for smaller spaces with the same ratio. It takes about a minute for the reaction to take place, the liquid will turn yellow, and for about 3 hours it will release chlorine dioxide as a gas. Take similar precautions as with ozone for airing it out and re-entering.

Four Methods for Cleaning Mold from the AC (HVAC) System of the Car

1. Take it to a Dealership – Have them Clean out the System

Skill Level – Easy. Results – Can work, depending on which methods they use.

how to clean mold out of the AC system of a car

There are a number of different cleaning methods used by automotive repair shops to clean out the AC system. Some use ozone and even run it through the HVAC in the same way as described in the next section on ozone.

There are also treatments that are similar to #4 on this list, introducing a product into the system to clean the evaporator.

One mechanic explains: “one is a mist treatment, using a product which foams up. You drill a hole in the case and then introduce the mist to the evaporator core and let it sit, give it time to work, and then flush it out.” (source).

Some of these might have fragrance of other toxic additives but others would be acceptable for many folks who are sensitive.

2. Using Ozone Through the HVAC

Skill Level – Intermediate. Results – works on most mold and bacteria.

how to use ozone to clean out a car or AC system

This is a technique used by some car detailers and dealerships and mold sensitive folks.

The simplest way to do it is to run an ozone machine in the car while the vehicle is running so that the ozone is pulled in through the air intake. Most people would run this through for a couple of hours. Depending on the amount of ozone and the time you run it for, you may need a window open to provide oxygen.

If you are running the machine in the car I would use a small machine like the ones on Amazon for under 100$.

Instead of running the vehicle, you could alternatively, hook up the battery to a battery charger to run through the HVAC settings that way.

For any serious contamination or if you want to blast this more directly through the HVAC, mold avoiders tend to use an external ozone machine that pumps in the gas, giving the machine full access to oxygen outside. Bioblaster is the most popular one.

If you are in the Facebook group Mold Avoiders, you will be able to see an example of a Bioblaster hooked up right to the air intake here.

That machine is overkill for me. But others may need this. I would have no problem running the smaller ones on Amazon that I have used many times and pumping those through the HVAC system with tubing from the outside.

To get it through all the different parts of the HVAC system, the ozone needs to run through it on all settings (heat, AC, recirculate). Run it through each setting for at least 20 min. The next section explains more about how to access the air intake.

This is tricky because of how far away you need to be from the ozone. Let it air out each time before coming close enough to the vehicle to change the settings. Again, ozone precautions are here.

3. Spray Through the Air Intakes

Skill Level – Beginner to Intermediate. Results – May or may not work.

spray in the air intake to kill mold in a car
The air intake is usually right under the front windshield

In this method, hydrogen peroxide or quats are sprayed through the air intake.

Some very mold sensitive folks have had success with 10% hydrogen peroxide sprayed into the air intake with these video instructions (not with toxic products like scented Lysol). Seeing the process in a video really helps to make sense of it.  

Spray the hydrogen peroxide through each setting for 3 min. You can use this mister.

You will be using 29, 30 or 35% peroxide (depending on what you can source) and diluting it down to 10% (here is the dilution table). Please research and take full responsibility for handling and spraying this concentration of hydrogen peroxide.

Some people found this worked better with quats (a type of ammonia). This ACDelco product was recommended.

4. Greg Muske’s Quats Cleaning Strategy

Skill Level – Very Advanced. Results – Likely to work if you do it right.

how to clean the evaporator core
From http://biotoxinjourney.com/clean-driving-machine/

Greg Muske from Biotoxin Journey has a detailed and more complex method of accessing the entire HVAC system and runnings quats (quaternary ammonium) through it.

You need some mechanical expertize for this method as it does involve drilling into specific parts of the system, which differ depending on your make and model.

You need someone who can understand the heater core diagram for your car, which you can look up online. You’re going to locate the evaporator core. Then drench the two cores by running about one gallon of quat solution into 3 access holes. Followed by a water rinse.

Greg also misted quats through the ductwork via the vents and the opening for the cabin filter directly above the blower (after removing the filter), and air inlet holes located under the hood next to the firewall. Unlike when cleaning the cores, this was not rinsed out. It was dried out by running the heater and fan on high.

Greg then cleaned out the rest of the car by using a steam cleaner on the carpet with Thieves Oil Cleaner. (You can use the cleaner of your choice). All other surfaces in the vehicle were wiped down with quats.

Full instructions and a video can be found here: Clean Driving Machine. This section was printed with permission from Greg Muske.

Corinne Segura is a Building Biologist with 6 years of experience helping people create healthy homes.

This post was written with input from an engineer, a mechanic, and a car detailer.

Did you find this post helpful? If so you can buy me a coffee to support the research behind this blog. Thank you!

What are the Causes of Mold in Tiny Houses?

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common areas that go moldy in tiny homes

1. Built by Non-Experts

Highly skilled builders are rare. They tend to focus on upscale houses because that extra work and time they spend to build something right does translate to more expensive homes.

Most tiny house companies I have seen were started by contractors who don’t have much experience, they certainly don’t have the expertise in building science (which is mold prevention), and high craftsmanship.

Most small companies I have looked at started with someone who had not even managed a whole house build before! That was the case with my builder.

Even if a company is well established, it’s rare that an architect or other building science expert is recruited as a designer and consultant on a tiny house build. It is necessary to have that building science expertise to building anything that will hold up to mold, no matter the size.

My resource page contains links to architects, builders, and building science experts who I think are good.

I certainly wished I had chosen an experienced builder who really cared about details, and hired an architect to design and manage the project.

2. Building Codes not Followed 

Building codes are not perfect, they are only the bare minimum requirements and even though they are just the absolute bare minimum of what needs to be done on a house, they are not usually followed.

To build a truly mold-resistant (regular) building you have to hit many of those codes right on and in many other areas go above and beyond those codes if you want the house to hold up to moisture and mold.

Tiny houses don’t even meet those codes on some of the most basic building standards. If you are having trouble finding a regular house that does not have mold, well, I don’t have good news, tiny houses are built even more poorly.

For some areas of the build, RVIA certification could help ensure things are done better. But some RVIA codes are not mold preventative (like the requirement a vapor barrier), that could make things even worse!

Look at RVIA codes and see if that will work with your moisture management system. You may have to forgo that certification. There may be important guidelines to follow there for general quality (plumbing, electrical, fire safety), but not necessarily for mold prevention.

You can build a mold preventative build (like this one) and also meet the International Residential Code (IRC) (which would be a good idea).

 3. The Trailer is Tricky to Insulate

All Tiny Homes on Wheels are built on a metal trailer – that’s a tricky interface for condensation in most climates. Building the house by using that trailer as a floor cavity is a bad idea.

The house should be built up on top of the trailer, and even then there are many very detailed decisions and details to consider and execute. See this post on a Mold Preventative Tiny House for details on the trailer base.

4. Metals Frames 

Many THOWs are also made with metal framing. That is really tricky too! Now you have a whole house with thermal bridging and the possibility of condensation in the wall. Even if you go with all foam for insulation, this has to be well thought out and designed well.

I have seen trailers with a metal frame and then an organic insulation! No!

The wheel wells, another metal area, are also particularly difficult to insulate and are usually done wrong. The wheel wells in my tiny house went moldy within the first 3 years. They need to be thought out and detailed right.

Hire a building science expert to design your building envelope.

5. Which Climate is it Built for?! 

Tiny homes are often moved throughout many different climates in the US and Canada. Which climate was it designed and built for?

Even if some thought was given to design the building envelope and HVAC for that climate, will it now be moved to many different climate zones? How will the house perform in those?

If the house is made for multiple climates that has to be factored into the design of the entire envelope and moisture management system as well as the HVAC right from the start.

WUFI is one program that you can use to model the moisture in the house and see how it will perform in various climates.

6. Movement is not Your Friend!

Taking a house and then jostling in on the highway does not lead to something very durable. All those little details that need to add up to have things perfectly sealed and flashed do not benefit from a lot of movement.

You can easily lose the integrity of your sealing or flashing here, you may even have trouble with your framing or siding. Problems with your framing could lead to problems with your doors and windows and more…

7. A One Year Warranty??

Many tiny houses are very expensive and only come with a one year warranty! What!

What other 60K item would you buy that only has a one year warranty? Builders can get away with a lot because major mold problems will take longer to show up than one year.

My house had a few problems in the first year, but there were other major problems that took more than a year to show up. Mold above the shower in the ceiling, mold on the framing, an insulation system in the floor that was not done right – I fixed these myself on my own dime.

Ben Garrett (Tiny Healthy Homes) who built my house only paid for things that went wrong in the first year. He then changed the name of his business (and so I could not sue him). That’s another reason these small companies are very risky. I lost 100k as a result of the building defects in that house.

Though I did learn a lot about building science when I took it apart! And this did lead me to become certified as Building Biologist to help others build low offgassing, mold-safe houses.

8. Siding is Prone to Mold

Siding is frequently done wrong on tiny houses. Mold preventative siding almost always has a rainscreen with very few exceptions.

Regular wood-framed houses almost always require a vented rainscreen siding system to prevent water damage and mold. This is rarely done on a tiny house.

Most houses I have seen have siding right up against the sheathing. Sometimes it’s permeable siding, meaning solar vapor drive can drive moisture in, but even if it’s not, it prevents drying from the inside out. And you are losing your layer of protection from water entering behind the siding.

A rainscreen helps water that will get behind your siding drain out.

I highly recommend Cheryl Ciecko’s course on building a mold preventative house which has opened up now for the January session.

To hear about future course dates you can sign up for my email list:

9. Roofing Prone to Mold 

Regular sized houses have a fairly complex roof system that often has venting. An unvented roof would have to be done really carefully.

In a small space, your roof cavity can start to mold fast. Mine did over the shower as the builder had no interior vapor barrier and the breathable roof sheathing membrane was enough to trap moisture there.

Many tiny houses also have roofs that are flat or don’t have the right material for the slope.

Here is an example of a highly detailed mold preventative roof.

10. Details not Done Right 

The devil and mold prevention are in the details. Window flashing, house wrap installation, house wrap taping, metal head flashing, the detail below the rainscreen, flashing on any permeations going through the wall, details around the door- all of these are super crucial.

It’s especially important to get right due to the lack of overhangs over windows and doors on most tiny houses. This means everything has to be done perfectly. The overhang on a regular house is insurance against too much rain hitting these vulnerable areas.

Simple Insulated Shelter for MCS and Mold Avoidance

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I recommend all of the products here, some products have affiliate programs and some do not. Upon purchase, I earn a small commission through affiliate links at no extra cost to you.

This post is about two highly insulated shelters I made with rigid foam, raised off the ground and covered in a tarp. 

These shelters are super simple, super tolerable for the chemically sensitive and are ideal for mold avoidance in cold weather (or even in hot weather).

This has the same insulative value that a house would have. I was very warm inside in Canadian winters with one space heater. This shelter can work in any climate, though it will not survive a hurricane! It was highly tolerable for MCS and a good set up for mold avoidance.

These shelters were an incredibly important step in me healing enough to live inside. The shelter was the last step in mold avoidance before I moved back inside. I moved back into regular housing for the first time in 8 years, and I continue to recover.

Living inside for one year now!

This is something I wish I had known about much earlier on, as tent living and custom trailers/vans are difficult to make and to live in, especially in cold weather. It’s hard to keep a steady temperature, it’s difficult to insulate trailers and vans, and it’s hard to keep them from going moldy. This shelter solved all those problems.

A wood frame like mine (pictured) is needed to protect the shelter from high winds and snow. My frame was very robust, survived a massive wind storm and big snowfall. If you don’t require snow and wind protection, simply tie up a tarp over the raised up foam shelter and skip the frame altogether. 

Building the Simple Shelter

The shelter is made of a plywood platform and a wood frame, though you could use metal or another material. We used some pressure treated wood for the framing and some non-treated wood.

Most of the points touching the ground are stumps, for added protection from rotting out (you can see that in the vide

The interior is an XPS foam box. The box was made to fit the plywood, it was 4 x 6 feet but you can make this any size you choose. The height we decided on was 6 ft. 

You can use any thickness of XPS that you want. Though for this to hold itself up without any supports (other than tape) as it’s designed, I would use 2 inches.

What I would do differently next time is paint the foam with ECOs primer and paint and possibly seal with shellac. This will seal in flame retardants and the very minimal off-gassing. Most extremely sensitive people do well with this foam<

I would also use clear tape next time because it would look better!

I would buy a tarp that covered the wood but still had air movement underneath.

When you are heating you should seal up as much as you can on the inside with the tape that you tolerate. Green painters tape or Siga tape are the most tolerated types. 

When taping the outside in heating season do not cover the seams fully, just enough to hold it together like in the videos.

In cooling season it’s the opposite (if you did put AC in there). 
Such a robust frame is not always necessary. You can build the plywood platform, with foam box on top and simply string a tarp over this if you don’t have strong winds or a lot of snow.

A number of details are necessary to control condensation on the inside of the tarp in heating season, as condensation can drip down onto the wood or foam. We used spacers on the sides, a criss-cross on the top, and a piece of plastic suspended above the roof of the foam shelter to stop water from dripping down and wood from getting wet and moldy. 

Please contact me for details if you want help setting something like this up.  

This shelter worked extremely well though there are things to keep an eye on in the long term. Here are some video tours which will help you to picture how it works, shows the spacers, and other details like windows and power. 

The whole thing was completed with some volunteer labor and some paid labor for 1000 CAD.  I used two 100 ft extension cords (10 or 12 gauge) to power this heater and my laptop and light. You need one dedicated 10-12 gauge cord if it’s 100 ft, for a 12.5 amp, 1500 watt heater. Plenty of heat for a small space! You can’t have anything else on that circuit in the house it’s running from or inside on that cord).

I used this plugin thermostat to control the temperature and keep it very even (which needed a surprising amount of offgassing). I strung up this bulb (the string needed some offgassing).

I used the Mondo King Thermarest and I covered it in two Husky bags (taped together) to keep it dry. A small fridge was kept outside in my trailer, on a different circuit. 

I used this little portable tub to “shower” in outside, and the luggable loo. More pictures of the framing:

 

Healing MCS with Mold Avoidance – Interview with Solona

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This posts contains affiliate links to the books I read and recommend. Upon purchase, I earn a commission, at no extra cost to you.

This is an interview with Solona, a fellow Canadian, who I have known in the online world for a few years. I have followed her journey from severe MCS, to planning effective toxin avoidance, to 85% recovery in just 4 months. She’s still in the journey, but is recovering quickly.
I wanted to interview Solona because she had and overcame the key bottlenecks which are:

  1. Assuming she was already avoiding mold
  2. Making an avoidance plan with brain-fog
  3. Finding a safe home to heal in

We talk about a couple books in this interview – the Beginner’s Guide to Mold Avoidance by Lisa Petrison, and Bryan Rosner’s book Lyme Disease Supercharge (which is actually about Mold Avoidance). I want to add Julie Rehmeyer’s book Through the Shadowlands to this list of helpful books in this journey.

INTRO

Corinne: This is my first interview. I want to do a healing from MCS, mold illness, healing from CFS series.

I want to talk about the journey from severe MCS, to quite a rapid healing journey.

STARTING WITH SEVERE MCS

I want to inspire other people who are starting out, who have high MCS, who want to go further with avoidance in order to get better. Not to just avoid avoid avoid and go in circles.

Is that correct, would you say you had severe MCs, I remember you talking about fragrance residue on packaging.

Solona: Oh definitely.

C: Did you have any other symptoms like fatigue?

S: I was diagnosed with CFS, I think about 20 years ago. I was bedridden for a few years. At my very worst, the scariest symptom I had was paralysis, especially around gasoline. I would lose the use of my limbs and I couldn’t walk or use my arms. And then I would get slurred speech. Those were the scariest symptoms. Then the garden variety ones also.

C: And I remember the forest fires, was that a big turning point? We are talking about the interior of British Columbia, Canada. The fires hit hard, 2 years ago, was it?

S: It was last summer. The big clue that this was mold, was that I relapsed after nearly 10 years of being mostly recovered. After being in Ontario. I went to Ottawa for a job. It’s really bad there and I crashed within about 2 months. I moved back to my home in BC to get well, then the forest fires hit in 2018, and even when they cleared I did not recover.

C: So Ontario was worse

S: Ontario was what made me crash, for sure.

BOTTLENECK 1: ASSUMING ALREADY AVOIDING MOLD

C: One thing I found really interesting ….We were both in the Canadian groups for MCS and other groups. I have seen you over time, though we haven’t talked on the phone, I don’t know you really well.

But one thing I saw that I wanted to talk about is I have seen photos of your house [where you were really sick right before avoidance]. I think at the time you did think you were avoiding mold. Is that because it was better than many other houses? And you were able to sense mold in other houses?

S: It’s because I never knew about extreme mold avoidance. I had a very good sense of smell so I can smell mold. I had no idea about outdoor toxins or molds you don’t smell, molds you don’t see. I was living in mold and I didn’t know it. And that’s why I didn’t recover like I did before. And I can’t really explain why I was OK in that house a few years prior.

But I can say I have recovered symptoms that never went away before, now, with mold avoidance.

C: Houses get worse over time if there are errors. It wasn’t a very new house, what was it from the 70s?

S: 70s yes.

C: I’m also in BC and the houses are not well built.

A lot of other people are in this stage now –  you had no visible mold, no water stains on the ceiling, right?

S: No, nothing obvious

C: No smell of mold. Did you have a basement?

S: No

C: basements are often musty, but you couldn’t get under it to see if there were any problems.

S: As I later learned, once I unmasked I didn’t really tolerate the area well for some reason.

C: When you started the more extreme avoidance you moved from one area of BC to another. Not extremely far. Some people do mold avoidance and they feel like they have to go to the southern US or even to the Caribbean.

S: I think it’s about 3 and a half hours [from the moldy house in Slocan Valley] to Kelowna [the first new location for avoidance]. The thing is, I learned through experience there are levels of unmasking. And I think I unmasked and cleared out and healed to a certain degree in Kelowna until I left went to an even clearer place [Idaho] and came back. I cleared out even more and now I don’t think I can tolerate Kelowna.

C: OK, you started in the Slocan Valley where your house was, then when you started mold avoidance you went to Kelowna and improved, and then you went to northern Idaho and improved even more?

S: That’s right. I spent a week in northern Idaho and felt incredible, and did a tonne of healing even in that one week. And then went back to Kelowna and instantly felt sick again and my symptoms got worse the longer I stayed.

C: [Going back in time again] I’m interested in that time, where you got a lot worse, you went to Ontario, probably hit a moldy building, came back and then hit the fires, and everything was really hard. But what do you think lead you to that shift [to mold avoidance]….

S: You did!!

C: Me?

S: It was 100% you. I was trying to find housing…..to buy a new house….

C: ….and I was like “no, they’re all terrible”

S: Yeah, well, no, it was when I decided….. I finally gave up… I looked for housing for ages, I finally gave up and made a joke that I will live in my car. So then I was posting vehicles. I put a deposit on a camper van.

I remember you said, “you don’t know what’s behind the walls”. And I was so discouraged at that point.

C: That was the one that was built out…. it was old. [Camper van build outs are very prone to mold].

S: Yeah it was old enough that it probably would have been contaminated. And I didn’t know about extreme mold avoidance, I hadn’t read the Beginners Guide to Mold Avoidance. I didn’t know all the nuances.

I was so discouraged I was like, “stop telling me the vehicles are not good!” So then that led me to actually read the book [Beginner’s Guide] and go, “ohhh now I know what she’s talking about”. I bailed on that camper van. And then changed my plan to actually doing extreme mold avoidance.

C: But you were in the mold groups, I wasn’t just coming into other groups and saying things like that! That was an extreme mold avoidance group.

S: And I didn’t know that it was different than what I was doing [already].

C: So, we’re going back to that time [again for a minute]. Houses are so difficult to find around here. You had MCS and some mold sensitivities. When you’re in that extreme level of MCS, you’re so limited. Usually people end up choosing moldy houses.

S: We are avoiding new houses because of the offgassing….

C: ….and maybe some have fragrance you are ruling out so many options, even just a cross-contamination of a fragrance.

So you were in the mold groups and the van was an idea, that van was tricky, I’m glad that van didn’t’ work out!

Then you found the most amazing vehicle of all time…

S: I researched probably 15 different solutions – inserts for trucks, medical transport, then I thought, what about an ambulance? Then that led me to the term Campbulance. I was watching van life videos like crazy to learn how to do it. I thought the campbulance would be more sterile and well maintained.

I found one being sold by the Province of BC. The Province gets rid of them every so often. I did tonnes of research and moved into an ambulance.

C: Ya, it’s such an awesome vehicle.

BOTTLENECK 2: MAKING A PLAN WITH BRAIN FOG

This is another key area. It didn’t seem like you had that much brain fog at the time.

S: Oh, I did at the time.

C: Cause now you can see the improvement?

S: It’s not as bad as it was in the beginning, but I was having trouble at work….

C: This was a critical time, you did have less brain fog or more clarity [than others], you were able to sift through the information, organise the information that was in the groups.

That’s another bottleneck stage. The first bottleneck, is thinking, I’m already avoiding mold because I can smell it in other buildings. The second bottleneck is how do I make this happen. What are the options and the solutions.

Do you think that looking at the struggles of others in the groups now. Do you think there was anything different about you at that point?

S: I think because I’ve been doing this for so long, MCS avoidance. I deliberately made a career I can do from home. My life has revolved around [MCS]. I don’t know that I could have done this just winging it if it was my first time, as quickly as I did it. I already had a job set up….

I also have a brain that is good with spreadsheets. I had spreadsheets with all the different vehicle options, all the features that I needed.

C: You had places lined up, you had places with wifi, since you need to work.

S: Exactly.

I listed and downloaded all of the apps, like freecampsites.net that show you where you can boon-dock, where they can show you wifi signals, I just researched all the places I could go.

C: I remember you even had a spot in case the fires did come (this last summer). Which was a lot of research.

[But], you also didn’t get into the bottleneck where you over-researched and just didn’t do anything. Like this ambulance could break down, this van is moldy, this tent might not work…

S: I think I got lucky because I didn’t do it perfectly at first.

C: No one does!

S: I made lots of mistakes but it still worked anyway. I think it just works out, you just keep doing it and it works out.

C: I think I want to stick that point a little bit, because you were able to do that strategic thinking planning comparing and get to the solution in a reasonable amount of time.

S: I think it’s a lot easier to do that when you have a sounding board, someone who is a little more cognitively with it. Now I have a few facebook friends and I help be their brain.

C: In the beginning, there are not a lot of people, and that’s why I do this as a job, there are not a lot of people who have the bandwidth and time to help the people that are in the beginning who have cognitive difficulties. I think it’s a key time for people to get help with the decision making. Especially if they are worse off than you.

Once I saw you get on a roll with it, I was like, oh, you’re gonna be fine.

S: 20 years ago I would have needed my mom, I was planning my trip to BC to get well, I told her I need you to be my brain. I think if someone is worse they need someone to lay it out step by step for them.

C: And now that you’re at the stage where you have some experience, you’re doing a little better and you can hook up with other mold avoiders who are in that stage and you can help each other. That’s a lot easier to find because you can mutually help each other. In the beginning, that’s a lot harder to find, because you’re the one in need. And a lot of people get stuck there. That’s a tricky spot if you get stuck.

BOTTLENECK 3: FINDING A SAFE HOME

[On to] the ambulance! I don’t want to talk too much about the ambulance because I could talk a LOT about the ambulance. We need to find out more, if we can find out how this was built. I think this has SIPS walls or spray foam. It is well built.

S: I asked for the blueprints but never got them. I just know it’s well insulated. A refrigerated truck is similar.

C: I want to dig deeper and I know other people are looking into custom building. Yours… I wish we could dissect it. It’s not very new right?

S: It’s a 2009.

C: It’s not too old. Most trailers don’t hold up that long [to mold]. There’s the fiberglass types. I go through all the types that tend to last a little longer but they all have their drawbacks. Yours I think is made like the older Camplites, that have a sandwich laminated wall. Or it just wouldn’t hold up this long. Maybe in 10 years when it dies, we open it and rebuild more of them like it!

That’s another difficulty – finding a trailer that is offgassed. I bought a Camplite when I was starting out, it was metal-foam-metal. I thought this would be fine. This was 8 years ago. It was so strong with the offgassing, it blew my mind. It reeked like glue. It was a well-made trailer, but I wasn’t able to use it until it offgassed. I regret selling it, because once it did offgas I should have kept it for emergencies or traveling. I just didn’t realise what a gem it was.

There are other options, vans that don’t have wooden walls and nothing in them….

RECOVERY, NOT JUST AVOIDANCE OF TRIGGERS

C: You actually made pretty quick gains…

S: I think the reason was that I spent 10 years in avoidance, and it was a pretty fast and short crash.

And this is why I knew it was mold, that mold avoidance is the reason I got well, because I spent a year in the Slocan Valley (in BC, Canada), which is as pristine as it gets in terms of MCS – no cell towers, I had the best water, the best air [in theory], and I still stayed stick for a year [after returning from Ontario], and then as soon as I did mold avoidance, within two months, I was like I’m going to go for a hike now. I went, WOW.

C: And then from there you got even better. So within the first two months… you started in Slocan, then you went to the Okanagan. Within two months you saw quite a lot of results.

S: I left in June and within two months I was slow hiking, by August I was feeling even better.

C: By now…. you started June….. it’s been 4 months.

S: It’s mid-October now, I’m in Idaho. The longer terms things are healing now. I had really bad psoriasis. My energy levels are even better. My diet and appetite are even better.

C: That’s so awesome.

Are you still sleeping in the ambulance.

S: I’m sleeping in a tiny house/cabin. That was built with MCS and mold in mind.

C: And you’re still feeling as good or better.

Yeah one sign of health is remembering my dreams and have lots of dreams, really good sleep, 8 hours. I have the best sleep now, I go walking every day, I work full time. We carry water, I can chop firewood. I can do lots of physical tasks I couldn’t do before.

C: Do you want to say what percent you are better?

S: 85%. That’s pretty subjective.

C: Yeah, some people would be thrilled with 85, and some people as they get better they will say they didn’t even realise there was another level of health.

I’ve also been sick for a long time and have trouble with those percentages.

S: I leave 15 % because I could do more intense hikes. And I also give it such a high number because some of the really scary things are better.

I can (but don’t) pump gas. I got diesel on my hands and brought it inside, and though, “oh, that smells bad”. And I was perfectly fine. For me that was a huge huge leap.

C: I don’t think people know I was as extreme as you, or close. I was floored by having someone else pump my gas [at my worst].

S: I went dancing and it was a room full of perfume – when I was really bad I would have been really sick after 5 minutes. In this case I actually danced for I don’t know, maybe an hour. Then I did get sick but I was able to step out and be OK. I’m not perfect where I can dance in a perfume room for 3 hours.

C: It’s [still] a lot of progress in a short amount of time. It’s taken me a lot of years to be OK around perfume. And everyone has such a different journey. It’s really hard to say how it’s going to go. Some people, their MCS disappears almost immediately, though they might not have been as severe as us from the beginning.

For people as severe as us, it’s not unusual that it’s going to take some time. Fast gains are always exciting though.

FINAL MESSAGE FOR THOSE WITH MCS

S: I think the one and only thing I wish the people with MCS knew, is that mold avoidance isn’t necessarily what you think it is. It took me years to realize it’s not what I thought it was. [Understanding the role of] outdoor toxins is HUGE. Understanding it’s not a smell. At least giving it a shot. I have heard a lot of people say I’m already avoiding mold. Which is what I used to say. Then realizing, oh, I really wasn’t.

I think the best way I can explain it, it’s not just your everyday average mold, it’s “super toxins”. And avoiding those is a bit of an art form, but it’s worth learning and at least giving it a shot.

C: I agree. What I see is that people with MCS and lyme are aware of mold. They are aware of the offgassing, the fragrance, toxins in the outdoor air. [All the toxins out there]. But some toxins are more destructive. If we can take out the bigger ones….

I will link to Lisa and Erik’s book, and Bryan’s book, I should add Julie Rehmeyer’s book as well, Through the Shawdowlands which is also very helpful. They talk about taking out the master toxin. Mold is one of the really key ones. Fragrance isn’t the master toxin. You won’t get out of this by avoiding fragrance.

I know for sure from watching this for 10 years.

—-

You can contact me for one on one help with problem solving for mold avoidance or finding safe housing.

Tiny Homes & Shelters for the Chemically Sensitive

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Updated in 2020

Related posts:
1. Regular-sized non-toxic prefab homes
2. Mobile homes on wheels for those with sensitivities
3. Emergency shelters for those with sensitivities

Simple, Small Modular and Custom Homes for those Sensitive to Mold and Chemicals

For individual help choosing the best tiny home or structure of your needs or a review of a tiny house company, you can contact me here for a consult. 

1. Passive Home Tiny Homes

https://unityhomes.com/our-designs/nano/

Besonwood is a high-quality passive home custom prefab company. Their custom Thoreau Cabin home is 150 sq ft. The owner chose the stone facade but that is not a typical facade. They are custom homes so they can built any size.

Their predesigned wing is called Unity Homes. Their smallest house “Nano” (pictured) is 477 sq ft. Nano Shell packages start at $65,000, and for a complete house it would be roughly $150,000.

They are wood framed with passive house design, made to high standards. This would not work for those extremely sensitive to offgassing as their walls include OSB and engineered wood framing.

The insulation used is Rockwool and cellulose in the model I saw (they have different wall systems to choose from). This is a house that mold sensitive folks should consider due to their quality work and indoor factory conditions.

2. All Wood Prefab

The Holz100 homes come in all sizes from very very tiny, small and large.

The walls, floor and ceiling are all wood, no glue, no nails. The roof will not be all wood, there will be another roofing material there.

I have a more in depth review in the general prefab post.

$35,000 BASE PRICE (CAD) for the 93 sq ft little module.

3. Metal Yurts

http://cleanairyurts.com/our-yurts/yurt-homes/

The metal yurt from Clean Air Yurts is 18 ft in diameter. The shell is made of galvanized steel coated in zinc. The door is metal as well.

You would need to build a foundation and choose materials for the exterior and interior, provide insulation and wiring and plumbing (if desired).

Though you could just leave it as a steel structure. The yurt can be assembled in one day and can be taken down and moved if needed.

Metal walls are very difficult to insulate in cold climates.

The cost of the metal yurt is 10K

Grain Bin Home – Another Yurt Like Option

These Grain Bin Homes are also 18 ft in diameter and made of galvanized steel. There is room for a loft and it has louvers that can collect rainwater if desired. Other options include solar panels.

It does not come with options for interior/exterior or foundation, so those would be up to you.

The homes are around 10K but there is a big discount for non-profits who are purchasing them.

Same as above, metal walls – tricky to insulate in heating climates.

4. Wooden Treehouse

From Out N’ About, a company that rents out treehouses, sells plans and parts, this 16′ Treezebo Hexagon could be a great non-toxic home.

The plans for the treehouse are $450 and that includes a 3-hour consultation. The metal parts are $2000-2500 and the wood would come to around 5-10k, not including materials for wiring and plumbing.

I like this simple option if you don’t need insulation. A rot-resistant wood and no need to worry about the foundation type simplify things here.

5. Arched Cabins

The basic kit for Arched Cabins includes kits include floor plates, ribs, ridge beam, standard R13 insulation, Super Span Roof Paneling, trim and fasteners needed to assemble the cabin.

Arched Cabin kits do not include the foundation, installation, interior, end caps, delivery.

What I like about arched cabins is that there are no leaks with this one piece roof.

In this design, you can use spray foam insulation (with or without rigid foam) without worrying about exterior leaks getting in behind.

The 12×12 kit is $2400. This is a simple, mostly metal kit that you could then customize to be chemical-free on the inside. 

6. Plastic Domes

These cool Intershelter domes are easy to transport and assemble and have a lifespan of 30 years.

The larger domes are made of a fiberglass composite material that the company says does not emit an odor. Some sensitive people say fiberglass needs some time to offgas (1-2 years or more) and others find it ok fairly soon after production. 

The small domes are 14 feet and are made of ABS plastic, which is a really safe plastic (the same plastic the LEGO is made of). This one they say has an integrated foam component.

The domes start at  $7,500 for the 14′ model in 2017.

Installing foam in the larger domes with an exterior vapor barrier is not simple in heating climate. If you are in a tropical climate this might be ideal.

A similar dome that Intergalactic, is also fiberglass, but the insulation is integrated.

Assuming the insulation is done well here and it is not prone to leaking, this would be much easier than trying to put foam insulation on the inside of the one-panel fiberglass dome.

In theory that would work better in heating climates (cold climates).

7. Plastic Homes (Non-Fiberglass)

Plastic Lego-Like Block House

EverBlock makes plastic blocks that fit together like lego. You can make a simple structure out of these. It’s a safer plastic than fiberglass that is much more tolerable for the chemically sensitive.

8. Plastic Module Homes

coodo.com

There are a few designs that are using metal framing with a plastic body. I find this design extremely promising.

The Coodo above, is made in Germany, and can deliver all around the world. A similar company, AluHause is American, with a show house in Palm Desert.

The downside is that fiberglass does offgas and won’t work for many sensitive folks, at least not right away.

Both have the potential to be very waterproof and mold resistant designs. Neither one gives too much away on how it’s built exactly.

Just like when looking at larger prefabs you have to go through the reconnaissance process outlined here.

The Coodo is 61K British Pounds for the base model.

Another similar model is the Haus.me which I go into more detail on in the prefab article. This one looks to be a different type of plastic, not fiberglass, though they don’t say which type. They claim that it doesn’t offgas.

9. Simple Wooden Cabins 

Solid wood very basic wood cabin


Leisure Cabins bare bone wooden cabins are made of solid wood. I see some OSB in the subfloor but that could be avoided. Opt for solid wood for the roofing as well.

There is no insulation so they would be difficult to live in in extreme temperatures.

It does not include roofing shingles and roof prepping, stains, railing, foundation and deck or windows. You do your own wiring, plumbing, and systems as well.

This version is a thin wood wall, not very warm. And when you start to insulate something like this you start to get into a complicated design. In that case I would prefer to go back to a prefab like the Unity Homes on this list which already has a well thought out wall system.

It is $6500 CAD for a 14 x 14 foot cabin. They are produced in Canada. 

Amish Built Wood House

From Backyard Buildings in Maine, these tiny houses are a good deal. They are custom built. This one pictured is from a member of the EI groups on Facebook and I have her permission to post about it.

The house is made of local wood, non-fiberglass insulation, low VOC adhesives, a woodstove (but you could use electric heat), wired for on-grid (but can do off-grid as well), cedar siding, metal roof, and plumbing.  

This does become a complicated system to design when you add insulation.

When I tried to work with this company, it was difficult to communicate with the builders (because of lack of technology/being Amish). They were mixing some traditional building with some more modern techniques like adding exterior foam insulation.

They can be moved though they are not on wheels. This one is 400 sq ft and was only 14K! I would only get a shell if buying something like this.

A Traditional Log Cabin

https://www.montanamobilecabins.com/projects-updates

For a thicker wood wall look at a company like Montana Mobile Cabins. This true round log cabin does not use insulation.

I much prefer this simple design than to try and insulate a wood framed cabin. This is a much safer bet for mold prevention.

Prefab Square Log Cabins

I like the thick square logs too.

Confederation Log Homes above makes custom prefab log homes with square-cut logs. The company has been around for a long time.

This is the first log home company I would look at due to their extensive experience.

10. A SIPS House

The Nomad Micro is a metal SIPs house. It can be made to be very non-toxic.

They are 28K CAD for the 10×10. You need to add: shipping (From Vancouver BC, platform or slab, installation, wiring, heat, plumbing, hot water heater.

There is an option to complete the inside in a non-toxic way. My most sensitive friend tested the SIPs and thought they were good.

Nomad has stopped production of the 10 x 10 and only produces the 13 x 13 now. They have also changed the basic design of the units since I first posted this.

I do see wood mixed in with this metal structure which I would remove in the design. But if they do use metal framing with metal SIPs I still think this is a good idea.

10. Hemp House

Hemp House Pods – a simple 8 x 12 structure meant to qualify as an ADU (without a permit) is made from hemp and a wood frame. Hemp may be mold resistant in certain climates.

I would have this reviewed just like all the others. I would use huge overhangs and I would look more closely at a foundation type that does not wick moisture up.

The cost does not include plumbing, electrical or the deck.

The houses are 15K and they say they go up in a week.

A Note on Exterior Metal and Fiberglass Shells and Mold Prevention

A prefab house that has a metal or fiberglass shell that does not have a rainscreen system is extremely difficult to insulate in most climates where houses are heated. This includes container homes.

“In a cold climate during the heating season, moisture vapor inside a building is driven outward into exterior walls. When it reaches a surface that’s below the dew point, the vapor condenses into a liquid.” (source).

In this case that “surface” where moisture in the air condensates is that metal or fiberglass shell.

To try and work with this problem you need airtight insulation. This could be 2 part closed-cell polyurethane spray foam insulation. This offgasses too much for most people with chemical sensitivities. It also causes the challenges of exterior leaks going undetected. Arched Cabins has a nice design because there are no seams or permeations.

The second strategy is to use rigid foam insulation and make it airtight. This is also tricky. Foam can be taped or sealed with caulking or 1 part canned polyurethane spray foam, but it’s difficult to keep it airtight. And any gap of air behind the foam can have air with enough moisture to condensate in some climates.

Mold Preventative Design

Options:

  1. In heating climates, it’s easier to have a well-designed wall system that has the proper air barriers (likely no vapor barrier), and a rainscreen – in short, built like a regular house with all the complexities of the wall system but with great attention to design and execution of detail.
  2. A monolithic wall – I tend towards simple buildings that have fewer areas where mistakes can be made. Monolithic walls (a single wall, made of one solid material) is easier in this sense. Log cabins, solid concrete walls, and solid earthen walls are examples. This doesn’t mean they will work in any climate and are foolproof. You still need a building science expert (like an architect) to design the system as a whole and make sure that the wall type is properly designed and executed and well as maintained.

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Corinne Segura is a Building Biologist with 6 years of experience helping others create healthy homes.

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A Guide to Non-Toxic Camping Gear (And Keeping it Mold Free) | 2020

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I have updated this post after having spent 2 years of close to full-time camping. The focus is still on avoiding chemicals, but I am adding more unusual camping equipment and techniques for avoiding mold, updating new gear I really like, and some new tricks.

This post contains affiliate links wherever the brands I like have an affiliate program. Upon purchase, I earn a small commission at no extra cost to you.

For individual help on choosing the best camping gear for you, and how to keep it mold-free, you can schedule a consultation with me here.

Choosing a Tent Type

A Cheap and Easy Start – Pop Up Tents

non-toxic pop up tent, offgassing

I bought a pop-up tent as my first tent. I went for one of the cheapest options here just to get started quickly. I was able to use it after one week (with the doors all open at first for air) but it was about 1 month before I found it offgassed the chemical smell, and I could close up the doors. I was super sensitive at that time.

A number of brands have pop up tents in this style which are super easy and quick to put up and have a decent design in terms of the amount of ventilation (more on the style I prefer with ventilation below).

Mine leaked in heavy rain so I don’t like this style of tent, other than the fact that it is very easy to pop up and if you get a good tarp over it you will be waterproof – I always put a tarp over now, more on that later.

Anyone super challenged with putting up tents might want to start here.

Rain Fly Styles – Preventing Mold and Avoiding Chemicals

For heavy rain, a tent with a really good rainfly is needed that comes down almost all the way to the ground like many of the REI or MEC brands and this Backpacking tent (pictured left). I used the Winterial version of this style for many months.

When it comes to tents on the ground, this is the main style I look for because of the good rainfly which keeps it more waterproof.

Having mostly mesh on the inside also reduces your exposure to chemical offgassing and helps to prevent condensation on the walls.

Technically you don’t need a tarp over it, but I always add one. Water that soaks the tent walls will then soak anything that is touching the walls inside. The tarp is also needed so you can get in and out when it’s raining.

I just don’t trust any tent enough to not put a tarp over top. More on setting up tarps later in the post.

Offgassing Tents

Sometimes the rainfly smells stronger than the tent and sometimes it smells less. Sometimes a super beefy tent bottom is the hardest part to offgas. It depends on the brand.

Some who are trying to reduce exposure to chemical offgassing and flame retardants wash the tents to remove some of the treatments, but this also removes some of the waterproof coating. That can work if you have a good tarp over.

I have not found any evidence that many flame retardants can be adequately washed out, but it can’t hurt to try.

I like putting tents in the sun to offgas them. Smell them to test, and also touch them to make sure they don’t cause skin irritation.

The more mesh you have the more airflow and the less exposure to offgassing.

Stealth Camping – How to Camp on Balconies

For stealth camping on patios and balconies of hotels or Airbnbs I have used a one-person tent like this, I also like this Tenton brand (I like that it comes with straps to strap it to a camping cot below to raise it up).

You can also look for tents called bevy tents.

I have tried just a mat with a mosquito net over it, and I have also just strung up the just the rain fly (with no tent) over a camping cot and Thermarest if there are no bugs.

Otherwise, you can cut out the bottom. Never put a tent with a bottom right over outdoor tiles, bricks or concrete for long, you will have a recipe for mold fast.

You can put up a tent on top of a camping cot like in the pictures of the Tenton one person tent linked to above. But to keep a low profile I prefer to use a camping cot and then string up the rainfly or mosquito net so it does not go higher than the balcony rails.

Putting up a Tent when Disabled 

Make sure you know how (and that you can) put up your tent alone (as well as set up other supplies like a stove) before you get to the campsite. I have shown up to campsites with tents that are defective or missing parts more than once, so I would do a trial run for that reason as well.

For those who are disabled and limited, I made this video on Camping for Those Who Can’t Camp, to try and give some examples of how camping might still be possible for you.

Brands of Tents that are Low in Offgassing

Moonlight thetentlab.com

Brands that seem to be the lowest in offgassing are:

  • Lightspeed (polyesters with PU coating) REI (polyester, rainfly, and floor coated with PU)
  • LL Bean (polyester with PU from what I have seen)
  • Big Agnes (nylon, polyester with PU and some silicone).
  • The jury is out on Coleman, some people tolerate it and others don’t.
  • Some people find cheap Walmart tents especially Ozark brand is more tolerable than ones for hundreds of dollars. I have found Ozark tents to be very tolerable myself.
  • Cuben fiber tents – Cuben Fibre is PET – polyethylene plastic, this can be more tolerable. Many have said these don’t contain FR, but Zpacks failed to get back to me on that.

There is no consensus on which brand is the best for those with chemical sensitivities. Everyone is so different, no tent is perfect, and for some less sensitive there might not even be a big difference between the brands. You have to test them out for yourself if extremely sensitive.

Silicone treated tents might be more tolerable for some, others may prioritize avoiding flame retardants.

10 Tent Brands without Flame Retardants 2019 

  1. Sierra Tensegrity Elite tents (Amazon).
  2. Mountain Hard Ware tents made after 2019 are FR-free (Amazon).
  3. TarpTents
  4. Fjällräven tents (Amazon).
  5. Diamond Brand tents (Amazon).
  6. Nemo Some tents do not have FR. (Currently, Apollo and Chogori, says the company).
  7. Moonlight All FR-free and coated with silicone on the outside and polyurethane (PU) on the inside.
  8. Winterial does claim no flame retardants in discussions although the brand is not one that publicizes this
  9. NatureHike has claimed no flame retardants, but it’s not written anywhere other than private emails (Amazon)
  10. Six Moon Designs SilNylon, Silpoly and Dyneema Tents and Tarps are not treated with any fire retardant materials

Some canvas tents do not have flame retardants.

Cuben fibre from what I have seen is FR-free

Camping Gear without Flame Retardants 2019

  • None of the Thermarest Camping pads contain FR. Some have the Prop 65 warning (but for chromium)
  • The Exped mats are FR free since 2015 the lot.
  • REI brand sleeping mats are not treated with FR.
  • Wildkin sleeping mats and sleeping bags are also FR free.
  • Two other sleeping bags that are FR free are Holy Lamb Organics (but they use cotton), Kelty, Wiggy’s, and the down quilts by Jacks ‘R’ Better.

Should you go with an Unconventional Tent?

Aluminum Insulated Tents

These Billion Brick tents are insulated and the foil on the inside will also block most of the VOCs from the fabric on the outside. They say you can sleep in them down to 0 degrees Celsius. They are 269 USD. They do not have any mesh for ventilation which I imagine would be quite the problem for condensation and I do not know how you would get fresh air. This doesn’t seem realistic for me.

The Shift Pod is another version of an insulated aluminum tent made for Burning Man. The benefit to the aluminum on the outside is it’s reflective of sun and heat. I would think it would have similar problems with condensation in most situations. It’s pricey at 1300 USD.

For 18 USD you can get this aluminum lined small sleeping tent (that might work for balcony sleeping or in an emergency, otherwise it’s difficult with a lack of ventilation). The aluminum on the inside is more tolerable than the usual plastic.

Make Your Own Tent

Others have made homemade tents with materials they can tolerate like Tyvek, Reflectix or XPS sheets. You can also make a more typical tent from untreated nylon.

More info on that in this post here.

Canvas Tents, are they Mold-Prone?

Some folks who cannot handle the chemicals in the synthetic tents have tried canvas tents. These do not hold up well to rain and high humidity and I would not use them in rainy or humid conditions nor expect them to last very long at all.

Some companies people like are Reliable Tent,  Kodiak Tents, Davis Tents.

I have seen canvas tents, specifically, Davis tents hold up for quite a long time in a dry climate and with a woodstove inside. It can take rain and even snow, as long as it can dry out. For long term living a gravel floor or a raised up wooden platform is best.

For those who don’t tolerate cotton or who want the tent to hold up a little longer than cotton canvas, you can make one out of hemp fabric, like this one. You can expect cotton and hemp to last a short while in dry non-humid climates where you are expecting very little or no rain for a while.

If you are making your own tent out of canvas or nylon you can use the tube structure of a conventional tent and build it around that.

Large Wall Tents

Wall tents can be canvas or conventional nylon/polyester. They have straight walls and are generally larger. Barebones makes a nylon polyester wall tent. Often this type has more weather poofing and will have flame retardants because they are set up for wood burning stores.

This can be a good solution for a longer-term camping tent. Though you should take care to keep the base dry (cut out or raised up) if you want it to last.

How to Stay Dry and Prevent Mold when Camping

How to Set up Tarps Underneath and Over Tents

I bought a tarp for underneath to keep dew from getting the tent wet from below (also called a footprint), and later I added a tarp for over the tent to stay dry. The bottom of my tent stayed nice and dry at first with the tarp underneath. I would take out and turn over the sleeping mat every day.

If the bottom of the tent gets wet you will want to dry it in the sun within 24 hours (flip it and then put it back and maybe move spots). You can use the footprints made for underneath tents but tarps are generally cheaper (your tent may come with a footprint).

You want the tarp underneath to be a little smaller and tucked in so that is is under the tent. No water should get between the two. Some people tuck it and then raise it a little with sticks or rocks so that no water gets in between. I tried that but in the end tent bottoms still went moldy on me if I had damp soil.

Putting a tarp overtop helped a lot. I found regular tarps from the hardware store has a strong smell but offgassed within a few days. I use a silnylon tarp which has a less offensive odor but is more expensive. Over most tents, you need 12 x 10 or 12 x 12.

Some people find they still do have to move the tent every couple of days due to condensation or the earth going funky underneath.

Keep a backup tent that is offgassed in case of mold or damage to your primary tent. Keep backup gear especially if you are out in the wilderness, if you need geat to offgas before using, or you cannot easily drive somewhere and buy new gear within one day.

Generally, you string up the tarp up in an “A shape” so that it’s touching neither the tent nor the ground, you can also string it up with a shed slant like the photo above. Some people dig a small trench around so that the water that drips off does not go towards the tent. Without a tarp, I had a lot of problems including saturation of the tent and water coming through especially where anything was touching the tent.

In a major storm, a larger tarp overhead helps, as well as a deep trench, and if things are going swampy you need to raise it up. I have used XPS sheets to raise up a tent in a storm before I found the Cot Tents.

The Solution to Tent Bottoms Going Moldy – The Best Tents For Avoiding Mold

After throwing out many tents and then moving on to cutting out the bottoms, I have finally found what seems like the perfect tent: the Ozark Trail Two-Person Cot Tent (easier to find at Walmart Canada than in the US right now).

This is an integrated camping cot tent (pictured left). This is off the ground so the bottom will not mold. They do have the one-person version available in the US.

This had a very low odor rainfly and a brilliant design with the rainfly coming down way past the cot to protect water from getting in between.

This is the best design of a tent I have ever used, though it’s flimsy and broke on me when I took it down. It is assumed here that the Prop 65 warning here indicates the flame retardant “Tris”.

Although I didn’t like the more common style of tent cot (I had trouble with ventilation and even dangerously spiked my C02 levels one night), if the Ozark Tent is not available I would use this style again, but with caution with ventilation.

The Winterial brand is a brand I have done well with, though it was the Camp Rite brand that I tried in this style. The Camp Rite brand does have a two-person version.

I quite like the Tenton tent that is made to strap on to their XXL camping cots. You will, as always, want a tarp over this whole set up since this rainfly does not come past the cot (though on their website they sell a larger rainfly which would).

The tree tents look interesting, as they are raised off the ground, but you have to keep in mind these are really just for sleeping as they don’t look very conducive to hanging out all day. I wonder how much they sag in the middle, and they are not as easy to put up. For those who are less picky about their sleeping environment resembling a regular bed, the hammocks with nets are interesting options that are affordable and easy to travel with.

Downsides of Cot Tents

Cot Tents are Bulky

While I would never want to go with anything other than the raised off the ground tent again, this won’t work when I travel. When I travel I need to fit a tent, sleeping mat, and sleeping bag into a duffel bag.

The sleeping mats I use are huge and unless I can send a tent ahead I would have to go back to cutting out the bottom. I would use plastic bags to encase things instead of the thick tarps I mention.

Cot Tents are Colder

It is cooler when you are raised off the ground. But I don’t find it any worse than cutting out a bottom and using a camping cot (in fact I find it warmer than tents with the bottom cut out).

Flame Retardants

Ozark is a very tolerable brand for MCS. I don’t like the flame retardants they use. I have not seen a flame retardant free brand in this style.

Should you Buy a Cheap Tent or Tent that Lasts?

For those doing mold avoidance or living somewhere very damp, you might want to go with the more disposable option.

Expensive tents from REI and MEC tend to pack smaller and lighter and should be higher quality, however, if they do go moldy it is a bigger loss.

On the other hand, if I am traveling with a tent I want one that’s not going to break unexpectedly as many places around the world do not have stores that sell tents. Check also how much wind and rain they say they can withstand. You pay more for quality and wind and rain protection.

But all of that said, I would never spend more than 150 on a tent unless I’m sure it’s going to last me a long time (like the ones raised off the ground).

Camping Mats – Low Offgassing 

Air Mattress

I started with the Lightspeed air mattress which is the one the most sensitive to chemicals use. It offgassed quickly (2 days in the sun) and felt comfortable. It’s good quality but I had back problems with it. Many with chemical sensitivities prefer the Intex polyester air mattresses.

Other very sensitive folks have tolerated the small air mats. I was very impressed with how little this one smelled (less than the air mattress), and it’s a WAY better option to travel with, but I did not find it comfortable enough.

Go with the simplest, most compact option that is still comfortable for you.

Open Cell Foam Self Inflating

The Mondo King

I ended up buying the thickest Thermarest instead and LOVING it. This is as comfortable as a bed to me, though many people put Thermarests over a camping cot, that seemed excessive with the MondoKing (though cots can also help you get off the ground which is a benefit when you have cut out the bottom or are preventing mold under the bed).

I’m not that picky about beds so I was surprised that the airbed hurt. The Thermarest has a decent R-value to keep you warm, the more insulation you have under you in the cold the better.

The MondoKing is very comfortable and I usually wake up forgetting I’m in a tent. It has polyurethane in it but it offgassed quickly in my experience. I used it after 2 days of airing out (not ideal), in one week I found it to be really good, and one month to be near odorless to me.

This is a super good mat for a trailer or other tiny home as well. It does not contain flame retardants.

I bought the repair kit for the Thermarest as well because this is going to be my main bed in the trailer, I also carry the repair kit when traveling.

I still prefer the MondoKing, but another good and more affordable (but thinner option) I use is the Lightspeed version.

Camping Beds and Moisture

When it was hot and sunny (and I was not self-contaminating) I had no problems with condensation if I turned it every couple days and some days left it standing up to air out.

You will want to flip or air out your sleeping bag as well in the day to prevent mold.

As it got cold and I moved it into a trailer it became very challenging to keep a sleeping pad dry and mold-free. It needs to have slats underneath and a waterproof cover without a doubt in a cold or damp environment.

I wouldn’t recommend leaving this on any flat surface without a waterproof cover anymore. As I got more sensitive I was not able to keep this clean without an encasement.

If you are very sensitive to mold, very unmasked, or detoxing through your sweat, encase the sleeping mat right away. You can use plastic but I prefer these thick aluminized tarps as they also block the smell.

I used those tarps if I needed to block the smell but if I just needed to encase it I used contractor bags that are thicker than the usual garbage bags. I taped it airtight.

Closed Cell Foam Pads

For the ultra-sensitive to chemicals, an aluminized Thermarest is the safest camping mat.

People usually go with the solid foam or the small inflatable ones as they pack much smaller than the deluxe one I bought (and these are more affordable). They offgas less as well.

Here is a good overview of the closed-cell foam pads.

You can wash these unlike many of the other options. Some even pour boiling water on them to clean them and kill bacteria. You can’t do that with all camping mats.

Camping Cots

I like this style of camping cot the best because it packs really small, it is relatively flat, works well with a Thermarest over it, and it’s low to the ground but high enough to have airflow.

I never put a camping mat straight on the ground anymore. I always want that airflow under the sleeping mat (if you are not using an integrated cot tent).

I would not say this style of camping cot is easy to take apart and put back if you are physically disabled.

Bedding – Low Offgassing

Sleeping Bags

I’m extremely pleased with this Teton sleeping bag which is warm and offgassed after sitting in the sun for a week or so. I never even washed it.

I used this in the summer and some days it was too warm.

I am currently using this Abco bag, as when it’s on sale it’s a better price.

Others like a silk sleeping bag liner which keeps you warm and keeps your sleeping bag cleaner. It is much easier to wash a liner than the sleeping bag. I’m using this silk one and it’s quick to dry (surprised by how chemically it smelled, needed more washes than most fabrics).

You can also make a liner by sewing a queen flat sheet in half. You can either use a liner to get inside of first or to encase a blanket. This will keep the sleeping bag good for longer. The polyester liners can work too.

In warmer weather, I skipped sleeping bags and used heated blankets as my only blanket. As I started to detox through my sweat things got trickier.

Now I like a warm but washable option like these Pendleton Blankets. But, when it is very cold, a sleeping bag is really the warmest option.

Sheets

I use these AmazonBasics polyester sheets. But there are specific sheets for Thermarests and other brands of sleeping mats. They are also polyester, the only difference is they are fitted exactly for the Thermarest.

You don’t want any cotton in your tent – it doesn’t do well outside for long if it’s humid, and it’s terrible when wet.

Pillows

I bought a polyester camping pillow which is small (and it has cotton on the outside!)

I use waterproof pillowcases to prevent mold which I aired out and washed before using. They do smell at first, but polyurethane coating does offgas (to most people’s standards).

I have tried lots of camping pillows from the air and foam ones to the polyester ones, to just using a towel. You have to figure out which is the most comfortable for you. Some are very small. The air ones can be easy to roll off of. A towel is easy to wash if you need to wash gear often.

I keep backups of everything.

Staying Warm and Cool

Heated Blankets

I use a heating blanket in almost every climate. I thought the biggest problem for me would be stabilizing my temperature, but that ended up not being that difficult at all.

This is the Sunbeam heating blanket I use. After going through a lot of these, the trick is I want one big enough to cover me and I want the 10 hour shut off not the 3 hour shut off, to keep me warm all night.

They are challenging in how strong they smell when new and since they can’t go in a dryer they can be difficult to clean in cold weather camping.

I encase my current one in these liners and wash the liner every 3 days.

For those concerned about EMFs you can use this to heat the tent without putting in on your body. It won’t be as warm, but it is likely safer than a stand-alone heater in a tent. Or, the fancier and supposedly healthier option is an infrared mat.

This 60-watt heated blanket (the smaller throw size) will run for most of the night off this solar kit. I always have an extension cord running to my tent. A small heated blanket tucked into a sleeping bag provides a lot of warmth.

Using a Heater in a Tent

I have set up many a small heater in a tent. I check the wattage and if it has temperature control (I make sure my tent is big enough, note: read the tent dimensions carefully, they run small).

It’s safer to place the heater up on a small table or round of wood to keep it from knocking over or blowing directly onto something that could melt or burn. I make sure my tent is big enough to accommodate a heater with lots of space around it and it has an auto shut off when it falls over.

I use this little Honeywell heater because it’s super low wattage (250 watts).

I find it easy to accidentally shove this when sleeping and it can turn towards the tent fabric easily. That is just one reason why this is not technically recommended. It is a fire risk. This is what I have done, but I cannot officially recommend it.

If my tent is on the ground and I have a thick Thermarest, I can be warm enough with a heated blanket and that little heater down to 5 degrees C. I don’t sleep well when I’m cold, but everyone is different, so you will have to work out those details.

Other Heating Options

  1. Hot water bottles can be put inside the sleeping bag at night. This thermoplastic one has been reported to be very tolerable by many.
  2. Hand warmers work well when you don’t have electricity. Hand warmers in your sleeping bag can be a big help. The same company also makes sock liners. I have used these in power outages, they seem totally non-toxic.
  3. Heated clothes like battery-powered heated jackets, socks, and gloves can be a huge help as well.
  4. Wood stoves are used by some. I’m getting the Cubic Mini for the cargo trailer but I do not have experience setting up a wood stove in a tent.

Cooling a Tent: AC in a tent 

For the AC you will need to cut a hole for the exhaust and seal with tape around it.

If I put anything electrical in a tent I make sure I have multiples layers of protection from getting wet from above or flooding from below.

Use heaters, heating blankets AC or woodstoves at your own risk of fire or electrocution. They are not recommended for tents.

Here is the longer version of my Amazon visual list of my Favorite & my Unusual Camping supplies I bring with me on a Sabbatical.

(See the comment box on each image to see my notes on each one).

A few examples here:

  • I cooked everything in an Instant Pot when camping which I could do on my one extension cord.
  • Travel Berkey is still on my wish list, this ceramic filter is ideal for well water or any other water where filtering for biological pathogens is the priority (otherwise I buy water)
  • Non-cotton fast drying travel towel, I use this one.
  • Earplugs, and for really loud situations the “triple down” method of foam + silicone + ear protectors (or noise-canceling headphones). The construction ear protectors do smell quite strong. One benefit of noise-canceling headphones is some noises cannot be blocked without adding white noise.
  • The foam contoured eye masks smell a little and need some time to offgas (I put them in the sun). It is still my favorite mask many years later. The fabric ones can be washed to remove chemical treatments. I always keep a backup mask.
  • I still love this portable dryer, I got a tonne of use out of that. I used it outside with an extension cord, undercover.
  • Washable wool or silk long underwear, wool socks, and wool hat, gloves to stay warm in cold weather
  • Hand sanitizer (that’s my favorite non-toxic brand) and baby wipes are essential in a tent (unscented of course, for yourself and also if there are bears around).

More Resources:

Corinne Segura is a Building Biologist with 6 years of experience helping others create healthy homes.

I spent 2 years living outside in tents in order to bring down my chemical and mold sensitivities and get back into regular housing.

healthy home build consult

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Converting a Cargo Van For Mold Avoidance & MCS

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This post will cover converting a cargo van into a camper for mold avoidance (and for those with chemical sensitivities).

I will focus only on a few key areas: insulating in a way that will not go moldy – as metal walls are the trickiest thing to insulate because of the condensation factor. Most vans are built wrong and have mold (or will go moldy).

I will also look at MCS safe materials for the walls and interior, and a few appliances that are recommended.

Building a camper that will be both mold-free and chemical-free is tricky!

Keep in mind a cargo van can be anything from a metal box with a bed to a fully decked out camper with a stove, fridge, sink, heater, AC, and even a full bathroom.

I recommend all of the products here, some products have affiliate programs and some do not. Upon purchase, I earn a small commission through affiliate links at no extra cost to you.

For assistance with converting a van with materials that are healthy for you and mold preventative, you can contact me here. 

If you are not sure if you can tolerate the system for mold preventative insulation, I recommend getting in touch before buying a van.

camper van conversion low offgassing, low chemicals, for mold avoidance

Insulating a Cargo Van to Prevent Mold

The most important aspect of creating a mold-free camper is the insulation.

Here is the key point: no water vapor can enter the wall cavity, in most conditions, this means no air can enter or be behind the insulation.

With exterior metal walls, as soon as you are heating the van to the point where the exterior wall will hit dewpoint, you have a serious risk of condensation and mold in the walls.

So again, to keep it simple, no water so no air can enter the walls if you plan to heat your camper when it’s cold. What folks are reporting is no air at all should be trapped behind insulation if you want to prevent mold.

Rigid Foam Insulation

Camp Like a Girl was not a book I was a fan of. Sara uses some XPS and some EPS insulation. XPS is a vapor barrier (meaning no water can pass through 1.5 inches), and EPS is not. So using XPS foam is one option to insulate your van. XPS or polyiso with foil backing are usually tolerable for most people with MCS.

However, just the foam on its own will not be airtight. You can use canned spray foam to fill in the gaps if that is tolerable for you – the full system that is working, and was reviewed by a top building science expert, is to fill in the area behind the foam with spray foam and squish it in, leaving no air behind anything.

It is not chemical-free but I have found it odorless once dry. Handi-Foam is the safest one, as it is GreenGuard Gold certified. Great Stuff will work for many people. This method involves a lot of canned spray foam.

It also then needs to be riveted to the frame.

I would not recommend Sara’s method of putting in EPS and not sealing it – this leads to condensation, but because she barely heated the van and had hot temps in the day, this did work (at least for a while).

Any foam with air behind can be a problem when heated. Breathable insulation is even more tricky. A few cold days in a row and this will start to be a problem.

A good way to go about it is – if it’s warm enough – to sleep in the van empty and slowly work on insulating and building it out. The other option is to get it all done and then wait for it to offgas. 

Sara also uses insulation in the bed platform to keep the bed warm. I would be concerned here with flame retardants in the foam, and putting a bed on a flat surface is a no-no for mold.

In the bed section, I discuss how to use insulation under the mattress, or to use slats (unless it’s an air mattress, or fully 100% encased in plastic). More on protecting beds from moisture and mold and keeping warm in that section.

Spray Foam Insulation

Spray Foam is, in theory, your safest bet for preventing mold, as the foam will get into every crevice and form an airtight layer that will prevent all moisture from getting into the walls. 

The best spray foams are Heatlock Soy line at Demilic and Icynene Proseal (both GreenGuard Gold) (closed cell). Both are polyurethane foams, from reputable companies that are usually easy to source.

A reputable and very experienced installer is generally more important than the brand, as that is where the process goes wrong and can cause it to offgas majorly. (Though do go with a well-known brand).

The DIY kits for this type of spray foam are a definite no. And it must be closed-cell, which is a vapor barrier. 

I recommend these to healthy people who are set on spray foam. I don’t usually recommend them to people with MCS because of so many instances of prolonged offgassing.

In theory, they do not offgas, but I hear many many stories from moderately sensitive people that this does offgas noticeably in buildings. A small sample may air out quickly, but test this in a building before using it. At least two years (if this is installed correctly) may need to be scheduled into offgas this for the moderately sensitive. If not installed correctly it’s a goner, you’re going to be scraping out the whole thing. 

If you are mold sensitive but not chemically sensitive you could consider this in a van. I have heard though, both in Airstreams and in vans, stories of spray foam pushing out the frame in areas causing problems. A skilled installer may be able to clarify why this happens.

But Airstream themselves, as well as Winnebago, have moved away from 2 part spray foam due to problems. 

Wall and Ceiling Materials 

vans for chemical sensitivity and mold avoidance

Metal is your safest bet unless you are putting the plastic covers back on.

For an extra layer of protection, caulk around the seams to prevent moisture from going into the walls if you do put the plastic covers back on. 

If you want your interior walls to be another vapor barrier layer, the metal or plastic should be used and caulked airtight. The drawback is another step to being able to check on your wall.

If tin/aluminum tiles are used it’s best that behind them is airtight (though if you have enough insulation this might not be necessary). If you don’t have enough insulation to start with you could have condensation behind the wall cover. Some folks are putting canned spray foam behind the tin tiles for an extra layer of air sealing.

I have also seen gaskets with solid silicone sheets used to make something airtight.

In a cargo van or trailer, instead of using metal walls, my preference would be to keep the walls as simple as possible so that you can open them up to check on problems. You may want to use plastic sheets, or could simply cover the foam with the material of your choice.

I like silicone leather as a wall choice. Though you could also tack up polyester fabrics, the grey side of house wrap (which looks cool), paint foil or metal walls with AFM metal paint, polyethylene wall tiles (if you can tolerate the glue), or seal everything with shellac and then paint directly over XPS.

There is no reason to use PVC, the most toxic plastic, in areas like the ceiling tiles. But real tin ceiling tiles could be used as a non-toxic alternative which adds a fun look to your camper. 

While The Vanual looks very pretty with its wooden ceiling, I would avoid plywood as walls, ceiling or subflooring. There are just too many points where the wood hits the metal. If you are intent on getting this look, you would have to have lots of insulation at all the metal ribs to make sure dewpoint would never be hit.

If that is possible, then you could use plywood with strips of wood over it to get the look in The Vanual. Use a wood that can take high humidity. 

Floor Materials for a Van

non toxic flooring for cargo camper vans
Marmoleum Photo Green Design Center

I wouldn’t use wood to raise the floor joists as the wood right against the metal could be a recipe for condensation and mold. Rigid foam may be your best bet for floors to solve the thermal bridging there, with the same system of canned spray foam above and riveting used to make it 100% airtight. 

Different flooring materials that could be considered include:

Metal sheets, which could be painted with AFM Metal Primer with different designs for a pretty effect, or covered with rugs.

Marmoleum which is very tolerable. Be careful here as Marmoleum has jute backing. Use plenty of insulation underneath and an underlayment with a thermal break to prevent condensation. 

Hard plastic sheets, rolls of silicone, other rubber flooring if tolerable, Silleather, EVA mats (this formamide free one).

Woven vinyl (that one is phthalate-free), or hard vinyl planks (LVP) like Armstrong brand (which is plastic through and through) or Cali Bamboo which has a limestone substrate. Both are extremely low in offgassing, though still could be bothersome for some folks.

Plastic polypropylene click together tiles, super-duper easy to install. The brand is Europe is Bergo but in the US there are a number of them on Amazon like GarageTrac.

You could use wood engineered flooring or laminate if you are sure you have enough insulation underneath to prevent condensation from forming under the wood, a thermal break, and that the wood can withstand the humidity in your area. 

Subfloor

If you are concerned about denting, hard plastic sheets or metal. MgO board has worked for some but is prone to cracking and is permeable.

Interior Structures: Bed, Cabinets

preventing mold wood for ceiling and cabinets in a cargo van conversion
Photo Credit The Vanual

Sara and The Vanual used plywood for their bed bases. If it’s softwood plywood it needs a little time to offgas formaldehyde.

The other option is Purebond plywood (I wouldn’t use a non-moisture resistant wood species in a van or small trailer. Purebond does come in different species but as far as I know the glue is not made to withstand high humidity.

It also doesn’t let the mattress breath. Mattresses are very susceptible to becoming damp in campers. Even in a house, one should never put a regular breathable bed on a solid surface.

It would be best if the bed base was made of planks/slats that allowed some airflow. 

The bed should be flipped and checked often for dampness, especially if you cook or shower inside. Even better, in such a humid environment cover the mattress with a waterproof protector before installing it in the camper. This one is highly tolerable. 

The other option is to use a bed that doesn’t transfer moisture and doesn’t mold, like this well-tolerated TPU air mattress (takes only a couple days to offgas to my standards). But an air mattress won’t keep you warm. I now use the thickest Thermarest which is more comfortable than an air mattress for me (took a week or so to offgas enough for me) – this still needs a waterproof cover or to be raised off a flat surface.

I would use bedding made of polyester, wool, or silk, (and not cotton) because of the high humidity in vans. 

How to keep warm in a bare metal van 

Since insulation is so tricky, many mold avoiders keep the van bare. The best way to stay warm is to have insulation below you and above you.

Extra protection from the elements would be to add a canopy and heat sources:

I like the idea of adding insulation below you. There are a few ways. A thick Thermarest like the Mondo King does provide insulation.

But I like the idea of adding a layer of insulation below that. I like Thermacork. You could use foam, EPS polystyrene (the kind made for packing or crafts should not have flame retardant), it is also a little bit breathable. You then add your waterproof layer to your bed if you have it over insulation. (No air mattress in this setup, it won’t work). Then add a biomat or heating blanket.

Above you, you have your sleeping bag/blanket. Ideally for warmth, if you can tolerate it, your heating blanket is actually in the sleeping bag.

You can go one step further to stay warm and create a canopy or use a raised up tent inside the van. Anything to create a canopy – using the fabric of your choosing (as long as you have enough air) will keep this even warmer. If the area inside my tent or canopy is large enough for this to be safe – I add a tiny heater. I use this tiny Honeywell heater in all my small structures.

Cabinets

For cabinets, if you do use plywood, go for a formaldehyde-free plywood like Purebond (moisture resistant wood types only – the glues might not hold up to extreme humidity), offgassed APA exterior plywood, or use solid wood (which may warp in high humidity). I much prefer metal cabinets. 

Ventilation in a Van

You need fans that move air out – one above the shower if you have one, and one in the general space.

My CampLite had two fans and we still have problems just with cooking humidity making the mattress wet.

The standard camper fans are called Fan-tastic.

Van Appliances


 The Vanual has some cool tips for solar power, wiring, and appliances. If you want to go off-grid you will need solar and you generally you will need to tolerate a fuel stove. The Vanual and other van owners speak highly of Goal Zero solar systems because of how easy it is to install. Some people just use the solar charger outdoors.

The other option is to wire the van to plug into a campground plug (or modify to plug into a house), this would allow you to cook on an electric hotplate and would allow an electric heater.

Right now I use an Instant Pot to cook everything and I release the steam outside. This is a really good way to reduce moisture in a van or little trailer. You can cook almost anything in that.

Using an electric blanket is a good heating option to save energy. The best kinds are the large ones with the 10 hour shut off time to keep you warm all night. If you don’t tolerate those, a biomat may be better tolerated.

I would not use the stand-alone propane heaters that go inside as they will not be safe for those with MCS.

For cooking, if you are off the grid you will need to burn some fuel to cook. Cooking outdoors is safer. Alcohol burning stoves are safer than propane. Though this won’t be tolerable for many.

For a fridge, I would go with a 3-way fridge that can run on propane solar or AC electricity. Unlike in most trailers propane is stored inside so this could become a problem. The Vanual recommends running this fridge on solar or the car battery.

Here is an example of a fully decked out custom van made for someone with MCS (you would want to see how the construction was done if you wanted to copy or buy this one).

healthy home build consult

Corinne Segura is a Building Biologist with 6 years of experience helping others create healthy homes.

Did you find this post helpful? If so you can buy me a coffee to support the research behind this blog. Thank you!

Carl Grimes, Certified Indoor Environmental Consultant, reviewed the mold preventative insulation system for vans. Extreme mold avoiders are using this system with success.

Cargo Trailer Conversion

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Converting a Cargo Trailer into a Travel Trailer – Mold Preventative, Low-Toxin Design

converting a cargo trailer into a camper

I’m converting a small cargo trailer into a tiny trailer that can be used for sleeping and living. In the end, this model is only useful as a portable kitchen and bath. Other models are sturdier and may work better as insulated conversions.

The cargo trailer is a TNT brand DBL ‘A’ 6×12, White, 12″ extra height making it about 7 ft high on the inside. The extra height is well worth it I think for a sense of space.

Side and roof vent (side vents are so small that they bring in very little air. The roof vent can only be wide open if it’s not raining). RV door lock that locks from the inside (vital) and barn doors that lock from the outside (easier to handle than the ramp door). You may want to move the lock to the inside when living in it. Front and roof are curved in this one.

I recommend all of the products here, some products have affiliate programs and some do not. Upon purchase, I earn a small commission through affiliate links at no extra cost to you.

Costs in Canadian Dollars:

$6100 cost of trailer
$3600 cost of renos at trailer shop – metal floors, install window, take out plywood (much cheaper, and probably faster if you have the factory do these.)
$1500 cost of insulation
Labour for insulation and vapor barrier, foil and glue – lost track
$1300 Electrical (+ $185 for CSA inspection and approval – allowing me to legally park the trailer in Canada)

I have seen better prices in the US, you can go smaller and get a better price, but for me, 6×12 is the minimum amount of space needed to make a happy little home.

Joey was able to do this for $7000 with the factory doing most of the work. In the Facebook group Mold Avoiders on the Road, you can see people having smaller trailers renovated for under $4000.

Necessary Renovations:

plywood between skin and frame

Remove plywood.

Install window – 24 x 30 vinyl awning style to stay open even during the rain (you’re going to need air in such a small space). It’s vertical so that the framing did not need to be cut. I do not find the hard vinyl has a smell but you can use aluminum.

I wish I had put in two as it’s nice to have windows. One does bring in plenty of light through, along with the vent on the roof.

You can look for an RV window or you can use a tempered glass house window and reinforce the framing around it.

Install metal flooring 3/16 hot roll plate steel flooring, 1000 for the metal + welding. See this thread for an in-depth discussion on what type of metal to use.

Electrical work

A 30 amp panel with a campground plug and 4 outlets inside. You may be able to make do with fewer outlets but the electrician wanted a dedicated outlet for the fridge and one for the heater. Then I have one near the bed for a computer etc, and there is one up high to string up a light and run any kitchen appliances.

Have these renos done by the factory and not after you buy it. This was a huge mistake that costs me a lot of money and didn’t save me any time like I thought it would.

I should have known better as I had read Joey’s conversion story (highly recommend reading that for another version of a conversion and some ideas on what you might want to add. (I disagree that foam doesn’t provide a lot of protection from the cold and heat. 2 inches of XPS is R-10, that is really good).

How long it will take to customize one depends on the brand, the factory and the time of year. Add 2-3 weeks on to their estimate.

The back door in mine has structural plywood so that still has to be removed and needed metal reinforcements. The front end had plywood between the frame and the skin which was a major pain to remove. Look for a brand that does not have these two issues and you will save a lot of money.

If you want to do it yourself check out this thread (you have to sign up). Watching someone’s account of doing it herself is well worth it. You will see tips on taking out the plywood and choosing a metal for the floor.

Do the Walls Need Reinforcement?

A big question with cargo trailers is if you need wall reinforcement when you remove the plywood. There are two answers to this.

The first is that it depends on the brand, some brands will tell you that their trailer is good to go with no plywood, these have thicker frames like the steel CM trailers. Or some companies can customize it with thicker frames. See the pictures below.

The second answer is that the companies might say they are not strong enough but people leave it un-reinforced anyway. Erik Johnson, me and two other mold avoiders have taken out the plywood and not added anything that would replace it structurally.

Mine started leaking and the company that sold it to me claims that the reason it leaked is that the plywood was taken out and this means there is less stability and it’s easy for pieces to come apart and caulking to come loose. I have braced mine since.

If they won’t customize it without plywood, remove that part yourself and reinforce it (or don’t) yourself.

custom aluminum aluminum framed cargo trailer

The first picture is a customized trailer reinforced with aluminum frames. Very robust. If you look closely you can see tape between the frame and the exterior, a mold risk.

The second picture is a CM all steel trailer with a robust steel frame, the frame is standard and the company does not recommend reinforcement.

The third picture is a standard frame, with plywood removed. Though it’s not reinforced the owner is doing just fine with moving it around frequently. The brand is Victory.

This picture is my trailer it has the least robust frame of the bunch, while the seller advised that it could be reinforced for longer trips (he told me this after the insulation was up). I have now braced/added strapping.

Toxicity of a New Cargo Trailer:

A cargo trailer smells much stronger than someone might anticipate a new metal box to smell. An extreme avoider in a hot climate would leave it sit for about a year before using.

I have seen two people who have turned around and sold them soon after buying due to the strong smell. Mine is now a year old and not totally offgassed.

The smell comes mostly from the body of the trailer. It is a glue smell and may also be oils on the metal. There are many other parts that are non-metal (differ slightly between brands) that may include:

Caulk of different types, double-sided tape (you do not want to buy a cargo trailer with tape in the frame – this is a mold risk), plastic on the back of the RV door, plastic and glue (very smelly) in the vents to the point that you will likely not be able to use these vents for air, rubber and foam (glued on) can be found around the RV door, around the barn doors, and possibly around the window on some models, there may be tape holding up wiring, there is the usual plastic coating on the wiring, plastic light and light switch may be included, there may be spray paint on wiring, there may be caps on bolts, screen on top vent, there is also exterior paint which some people have said they are offgassing but I could not pick up a smell on.

In such a small space there are also the tires on the outside to consider – on a hot day you will smell these.

Rustproofing chemicals may also be added to the frame. (Thanks to Madonna Ramp for some of these materials from other brands).

A lot of this can be covered and you can see in mine that it is almost completely sealed up. If you buy one and it smells strong, give it time and/or seal it up like I did mine.

Every trailer takes time to offgas. Someone was able to get the company Mirage to build without glue or caulk, but she was not able to tolerate the trailer brand new. I would not recommend leaving out glue and caulk.

 Buying a Used Cargo Trailer: 

I did not see any used cargo trailers in my area when I was looking but you can sometimes find these. You would want to know what it was used for. Look for gunk and rust that will accumulate at the bottom around the frame.

Building out the Interior – How Mine was Done (The Second Time)

  • XPS Owens Corning Foam 2 inches on walls and floor (you can also use polyiso, the most well-tolerated foam, or EPS which is not a vapor barrier on its own but is usually faced with foil or plastic). 2 inches XPS is R-10. If you are going to a climate that is extremely cold, add another layer of foam – polyiso or XPS on the inside until you get a high enough R-value for your climate. The reason I chose XPS is that is has a high R-value and it doesn’t lose its R-value in very cold weather like polyiso does. I also could not find polyiso in my town.
  • 1 inch Foil-backed EPS on ceiling (because I needed something thin enough and flexible enough to be curved on the ceiling) (Note: This is backward, there should be more insulation on the roof but I wanted the roof to stay curved and the insulation to stay between the frame so I kept it simple.). The brand was R-Tech but I can’t find a link for this. I can add another layer of 1-inch foam if it gets too cold.
  • Great Stuff spray foam should be placed behind the foam and on the gaps of the rigid foam (airtight so no moisture gets behind the foam). There is one for small gaps and one for larger gaps you will need some of each. This then needs to be braced and riveted to the structure which is hard to do in many types of cargo trailers and I would not recommend these standard brands like the one I bought. 
  • GE 100% silicone for touch-ups to waterproof the exterior
  • A Fantastic Fan in the roof vent would be helpful for ventilation, drawing air out of the top will draw it in the window and turn over a lot of air. The fans also help with humidity. This has to be wired in with the electrical.

There is a rumor that spray foam will crumble with movement in a trailer but speaking with the company Great Stuff and some folks who have taken apart trailers they have not seen this be a problem.

EMFs:

All this metal and foil did not stop wifi or cell phone reception – it lowered my wifi connection only slightly. If you are concerned about EMFs consult with an EMF specialist and test out a metal structure before buying. In theory, it is a Faraday Cage that blocks out some external sources of EMFs and may intensify what is on the inside.

Fixing the leaks

My TNT Mirage Trailer has a number of poorly built aspects. The company took no responsibility for this and the leaks.

What has to be fixed on this model or checked on any model: The back doors were leaking, the top sil needed caulking, the door seals were not done right, the doors were bulging at points, bending the doors and adding gaps for leaks. The front diamond plate had nothing behind it, it was a negative lap – a poor design, the front wall should come all the way down. The front plastic cap on the top roof is also a negative lap.

Vertical seams have the ability to let in water in a big storm or when driving it in the rain. Always check windows, doors, and any openings. Screws should be caulked as well. Look for a well-done roof design. This roof design is good. I have seen custom designs with vulnerable roof seams.

Aggressively hose test this before adding insulation and know where the weak points are. After moving it is when things are most likely to come open.

When recaulking metal parts, attempt to open things up and get caulking between parts and not just over the seams.

These trailers are difficult and I would not attempt insulation in this style/brand again.


 Erik Johnson’s Cargo Trailer (MECU):

Erik is the pioneer of cargo trailer living. He called his trailer and camper MECUs (Mobile Environmental Containment Unit). Erik used EPS foam without flame retardants. I don’t know how he sourced this but I would think this is the kind used for packing, not insulation.

In Erik’s trailer, he left a gap (like I did at first) between the foam and the exterior. He put in weep holes at the bottom in case condensation did find its way to the back. Some trailers like mine come with weep holes.

He has said that there has not been any condensation at the back and he has had this for more than a decade. I put the insulation in front of the frame which created a space naturally behind it (though my floors and ceiling have no space).

This method did not work for me, major condensation formed behind the walls and I don’t know anyone that was able to get this to work.

Here is a video of his camper which is done like his cargo.

Other Trailer Options:

 You can build out the interior as much or as little as you like.

  • You could add batteries but consider how long these will last you away from plug-in power.
  • You could add solar panels but this doesn’t get you a lot of power, it may be easier to just buy a solar kit that is portable that is made for camping.
  • If showering in another building, campsite bathroom, or outdoor shower is not an option for you, you could install basic plumbing. You would want to avoid tanks and have very simple plumbing that goes directly out to a bucket or pipes out into a greywater system. You will have to make sure you are following the rules with greywater here. I want to avoid all cooking, showering, and clothes drying inside to keep humidity down.
  • Options for outdoor showers include simple bucket showers, passive solar shower (that one is PVC-free, unlike most of them), active portable hot water shower (this one comes recommended by mold avoiders), or an outdoor tub big enough to bathe in. A privacy tent can be used to shower outside or set up a toilet outside. You can also DIY and set up something simple like wrap house wrap around 3 trees, or tie string around 3 trees and the string holds up shower curtains.
  • You could install a simple camping or composting toilet inside or use it outside if you need to: some of the options are Luggable Loo, Mini Porta Potty, or Laveo Dry Flush.

Finishing the Interior:

Walls

Floors

For now I’m using these mats on the floor temporarily. They smell like straw.

I am currently offgassing Marmoleum (takes one month in sun to offgas) but I don’t like that there’s a jute backing under the Marmoleum against the metal, that’s a mold risk).

I had considered Cali Bamboo Cork (not sure yet how long it takes to offgas, definitely much longer than Marmoleum). 

Note: Flooring I ruled out: Thermacork decorative cork the only cork I know of that is heat-pressed with nothing added – not good for floors. It flakes easily and won’t last long.

Cork underlayment – I bought this and tested another one that claimed 0 VOC. It is going to need a lot of time to offgas despite these “0 VOC” polyurethane glues (not at all). A year later I have not offgassed the cork floorings (though they were not out in the sun for a year).

If you have space, I like this organizer. 

Heating, Cooling, Lighting, Laundry:

Kitchen:

  • I bought this fridge which needed a lot of offgassing outside including running it outside. This one smelled more than other brands I have tried like Danby. I like Walmart for fridges as well. 
  • I’m using this kitchen island which offgassed fairly quickly but you could use a metal version if you want to avoid wood (and wood sealers and glue). 
  • I offgassed this cutting board pretty fast. I’m just posting that because I love it so much
  • Thrift shop bowls 
  • This hanging basket to organize kitchen items 
  • I’m using a pressure cooker to cook – you can make almost anything in this. If you use it outside or at least release the steam outside you will have very little or no added moisture to the trailer. You can get away with no other stove, oven or microwave. You just need an extension cord to use it outside.
  • I’m going to buy the travel Berkey for drinking water, there is no plumbing in the trailer. Berkey is ideal for well water and water from campsites if you are not buying water. 

Bedding: 

In a high humidity situation like a trailer, tent or other camping structure it’s important to have a bed and bedding that will not go moldy.

My bed will be up on slats soon (right now I am turning the Thermarest over every few days – it went moldy so it is crucial to get it off the ground onto slats).

Cotton does not hold up well in high humidity, so I have used more mold-resistant materials.

Consulting

I am available for consulting to help customize a little “safe room” cargo trailer or custom made trailer. I can help with everything from choosing materials to managing the whole build.

I also help you to decide between different housing options, from building a conventional house, tiny house, trailer to setting up tent camping.

Corinne Segura is a Building Biologist with 6 years of experience helping others create healthy homes.

Buy Me a Coffee at ko-fi.com

Did you find this post helpful? If so you can buy me a coffee to support the research behind this blog. Thank you!