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This includes the top 6 American locations in four states: Arizona, Nevada, California and New Mexico. These are campsites for RVs and tents (some have cabins, but not vetted) where experienced mold avoiders have found a lot of healing within the last year. Many of these locations are tried and true for many years, but I make sure I have recent reports on all of them.

The brochure covers the basic information you need to decide on which one will be best for you, including:

Location, elevation, basics on the campsite (hook ups, bathrooms etc), how spacious they are, costs, proximity to stores, WiFi and cell coverage, temperatures (and other weather related details).

This post on the Locations Effect goes into more detail on what a sabbatical entails (and also what to bring!)

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What are the Causes of Mold in Tiny Houses?

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 companies started with someone who may not even have built a whole house before!

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.

2. Building Codes not Followed 

Building codes are not perfect, and they are only the bare minimum needed. To build a truly mold-resistant (regular) building you have to hit many of those codes right on and in many areas go above and beyond if you want the house to really hold up to moisture and mold

Tiny houses don’t even meet those basic standards on some of the most basic mold preventative building methods.

For some areas of the house, RVIA certification could help ensure things are done better. But some RVIA codes are not mold preventative (like requiring 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 and 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 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 from his mistakes.

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 I will post about to my Facebook page and email list when it opens again. (There will be a bonus for those on 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.

Guide to Non-Toxic Flooring 2020

Updated November 2019

There are many choices for non-toxic flooring suitable for the chemically sensitive or the health-conscious individual. The best options are real hardwood, polished concrete and tile. But specific brands of natural linoleum, carpet and engineered wood are excellent choices as well. I will look at a few options that are still non-toxic but not quite as healthy, like luxury vinyl plank, laminate, cork and bamboo.

This post covers Green Non-Toxic Flooring divided into three categories, starting with the purest options:

1. The Greenest Options (Dark Green)
2. Medium Green
3. Light Green

If you need assistance choosing the best floor for your sensitivities, budget, and area of the house, please contact me for a one-on-one consultation. 

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.

1. Greenest Floors "Dark Green" (0 VOC, No Offgassing)

i. Natural Solid Hard Wood 

non toxic green healthy real wood solid floors natural finish
Naturally finished floors by @wdflooring
 @fourboardwoodworks flooring & installation
@thomashartshelby photography
Natural wood flooring is usually my number one choice. However wood contains natural terpenes which do bother some, and they can contain anti-sapstain chemicals which could explain why some people react to wood used in building and not wood in the forest.

Aromatic woods like pine have much higher natural volatile compounds than maple, for example. Wood also has a higher possibility of harbouring mould than less porous materials. To prevent mould you should make sure your wood has been kiln-dried and kept dry at the store and  onsite.


There are plenty of green 0-VOC options for finishing wood. I used Hemp Oil on my floors, a "purest" option. AFM Poly BP is another great non-toxic finish. I go into detail on more options for wood sealers and stains in my post on sealers.


For subfloor glues, my top pick is definitely AFM Almighty Adhesive which is safe and highly tolerable. If that doesn't work for you, try Liquid Nails Subfloor Adhesive. You don't need to use subfloor glue though!

There are no VOC/HAPs wood fillers by Mohawk and ECOs for the nail holes.

Unfinished Hardwood

You can buy solid unfinished hardwood flooring from specialty flooring stores, as well as Home Depot, Lowes and Lumber Liquidators. Lumber Liquidators is usually going to have the lowest price. These big-box stores have networks of installers. I tend to go with the installers that work with Lumber Liquidators, but other stores have good networks as well.

Pre-finished Hardwood

Usually finished with aluminum oxide infused polyurethane and cured under UV lights, these are typically very well tolerated once cured. I consider this to be safe product even for the chemically sensitive. Test it first. It is close to 0-VOC. This finish has two main benefits, not having to finish it in house and the finish partially blocks the wood odour.

I have looked over Mirage brand as well as Mono Serra from Home Depot. Bellawood from Lumber Liquidators also uses the UV cured polyurethane with aluminum oxide - they claim low VOC.


Use solid wood baseboards - they come primed and unfinished (don't use MDF).

Non-toxic underlayment types are silicone backed paper (for the most sensitive) or Rosin paper. Nail down installation with a paper underneath is less toxic than the glue down method. You may need a small amount of regular wood glue on the last piece or you may be able to face nail.

ii. Polished Concrete

If polished concrete flooring makes you think IKEA warehouse, think again, polished concrete can look beautiful and be green and healthy.

The Retroplate system uses "liquid glass" (a modified sodium silicate) and is completely non-toxic and 0-VOC. This option is available across Canada and the US, you just have to find someone who specializes in that system.

You can do acid stains, add natural pigments, use white cement, or add white sand to Portland Cement to get many different unique and modern looks.

iii. Tiles

Types of Non-Toxic Tiles:

real stone tile, natural, safe for the chemically sensitive
Marble tile is good in theory, but most of it has a resin put on it at the factory to fill in tiny holes and fissures, and it might have a (chemical) sealant on it as well. A pure slab, or tile, that does not have a glossy finish can be sealed with a natural or low toxin sealer.

Slate is also good, you can find it unsealed like these from Home Depot. Though like marble, a resin is used to fill lines and pits. Both can be sealed with AFM Mexeseal or Meta CreamTung oil can be used on slate. Some types of slate are dense enough to not require a sealer.

Concrete tiles have beautiful designs. You may want to ask what additives are in the concrete and test these out for tolerability. I sealed mine concrete tiles with AFM Penetrating Water Stop. You can also use tung oil or Meta Cream.

Other natural stones like travertine, granite, soapstone and limestone are all great options for green healthy floors. Always check if a resin or sealer is already applied, and then check to see which natural sealers will work over the stone of your choosing. Honed stones (i.e. not glossy) are the easiest to seal with a natural pure option. Very dense stones like many granite types and some slate do not require a sealer at all (bonus!)

Budding green companies now make walnut oil and hemp oil that can be used on natural stone and concrete. Though I have not seen hemp oil used in this application, it is a drying oil, so this theory does make sense. Walnut is a semi-drying oil so I would have some reservations in putting it over a large area. The post on sealers explains this further.

Ceramic tiles have a high incidence of lead in the glaze Ask for lead test results from the company and do a simple 3M Lead Swab (those are useful on a number of household items and they are affordable). But to pick up lower levels of lead, you need to hire someone who has an XRF tool.

All ceramic tiles should be tested for lead. A client just tested American made tiles that stated they were lead-free, but when tested they showed high levels of lead. So it might be wise to test any glazed tile regardless of origin. And be extra careful when removing them as the lead dust is particularly harmful. Tile over existing lead tiles if possible, instead of removing.

Porcelain tiles are inert and safe. I have not seen evidence that porcelain tile contains lead. A benefit of both porcelain and ceramic tiles is you won't have to seal them.

Wood-look tiles claim to be 0-VOC even though there is a printed image on them. The glaze seems to block this. I have tested them and I do not detect anything that is different from regular tiles. Wood-look tiles are usually porcelain but can be ceramic.

Glass tiles are inert and healthy, most types are too slippery to use on the floor. Some have used some types on the floor, but I would recommend these only for walls and backsplashes.

A Note on Air Cleaning Flooring

Crossville Tiles have a coating option called Hydrotect. This uses the PCO process to clean the air. A layer of non-toxic titanium dioxide is used to coat the tiles. This reacts with UV light, and just like the PCO air purifiers I reviewed, it creates a reaction that can break down some bacteria, moulds, VOCs, and viruses. I don't know how impactful this tile coating will be to the overall air quality in a room. The company does have some reports that show a reduction in bacteria, which may be worthwhile for some folks.

If you read my article on PCO air filters you will remember that some people have a bad reaction to this process. It's possible that in a high VOC area it creates formaldehyde, or in a clean environment, it can create NOx. I would try out a PCO air purifier before installing this tile, to make sure it works well for you.

This air cleaning technology is also used on wood floors.

2. Medium Green (0 to Low-VOC)

i. Natural linoleum 

natural linoleum, organic safe healthy flooring chemical freeMarmoleum is made from linseed, binders, wood flour, limestone and dry pigments which are mixed and then calendared onto a natural jute backing. It's got a UV cured sealer on top, and this is the glue used to install it.

I found that after one month the odour all but disappeared from the product - though many people say the odour never disappears 100%. I am using this in my trailer. I was surprised and impressed since I don't normally do well with linseed.

The roll down flooring that I recommend (the sheet) is glue down. The tiles (MCT) are also glue down, they have a plastic backing (not PVC) it's slightly more rigid and would generally work better in a trailer. The "click" is the same sheet (roll down material) mounted onto a substrate of HDF and cork. It takes longer to offgas, but it has the advantage of no glue.

This is one of my top flooring choices, I recommend it often and it looks cool as well. I like many of the colours and the concrete look.

ii. 0 VOC Engineered Wood 

safe non toxic 0 VOC and low VOC, low offgassing engineered flooringWhile many engineered woods have significant offgassing (see section below), Kahrs brand has zero added formaldehyde and claims 0 added VOCs. I tested it and found it to be quite good.

Here is my more detailed review of my testing of this floor. Here are their test results with Total VOC 50 ug/m3, it's still not clear to me how three of those five chemicals are not added to the glues or finish, however that is still an extremely low level and two of the VOCs are terpenes naturally occurring from wood.

Despite all this, most folks do really well with Kahrs, and it is usually the first option in the engineered category I look at with clients unless they know this won't work for them.

The next option I would look at is Cali Bamboo Geowood. I really like their limestone substrate, it is highly tolerable and much healthier and than the standard substrate in most brands (normally substrate is a wood and glue mixture - the main the reason why this category has tended to be higher in offgassing). This one does claim formaldehyde-free and was tested by Green Design Center. The benefit here is less wood but the top does have more offgassing in my view than Kahrs and some other options.

Lauzon engineered flooring that is made in Canada also claims 0-VOC and 0 formaldehyde, but like Kahrs, when digging into their fact sheets on specific flooring, this did not seem to be the case on each type. Check out Anderson and Whickham brands which have also made claims of 0-VOC.

Use floating where possible, not glue down. The Kahrs underlayment is excellent.

iii. Carpet

For natural, non-toxic carpet or natural fibers and synthetics can be good. No flame retardants, no mothproofing, no stain repellent, natural padding and either no adhesive or a non-toxic adhesive. The most sensitive will want undyed natural carpet. Not all do well with the natural smell of wool though, and you might be pleasantly surprised with some of the non-toxic synthetic options below.

I have reservations about natural latex which are outlined in this post on mattresses, and I'm not sure if the same precautions need to be taken with carpet. I personally have a slight preference for synthetic backing.

Safe Natural Fiber Carpets

The best non-toxic chemical-free wool carpets are:

natural non toxic wool carpet no offgassing no flame retardants
Earth Weave from Green Design Center
1. Earth Weave - wool, no mothproofing, no other treatments, does contain latex. I always prefer undyed wool for the very sensitive.
2. Nature's Carpet  - wool - contains natural latex adhesive. The dark green line does not have moth proofing and uses undyed wool. The medium green line does not contain natural latex, which for me is a big plus, but it does contain mothproofing.
3. Natural Home Products - wool, contains natural latex, but checks all other boxes.

Hibernia wool. I have sniffed Hibernia and it does have a wooly smell (as you would expect), but not a chemical smell. The company has since changed ownership (2018). They do use moth proofing (typically permethrin is used on wool carpets).

Seagrass - I really like seagrass carpet because of how it feels underfoot. The DMI brand makes one I like that is not dyed or treated with insecticides or other chemicals. It does contain natural latex.

Non-Toxic Synthetic Carpet

Top two pics for non-toxic synthetic residential carpet are:

Home Fresh - My top pick for synthetics carpet (polyester), this carpet contains charcoal which absorbs some VOCs (up to a point) and was extremely low in odour and offgassing. The carpet does have Scotch Guard coating on it so I do not know how they can claim 0 VOC exactly. The backing is a built in felt backing, which seemed good to me.

I got a sample that was a few months old, but it has stayed bagged up, and I found it to be very good, extremely low in offgassing. I did not pick up classic carpet offgassing at all. Though it is not 100% odourless, it is close, and did not seem like an offensive odour to me. If you don't have an extreme sense of smell you may very well find this odourless. I was actually quite surprised as I have sniffed many carpets. This is my top pick for a green healthy synthetic carpet. Available in the US (not Canada). For $350 off, email me for a discount link or try this link.

(Note: I've been recommending them as my top choice for 2 years before they had this referral program and despite the company refusing to send me a sample directly or answer my questions. I just actually think this is an impressive carpet).

Flor 0 Fedora a low-VOC which is made from recycled plastic, it was less of that telltale carpet chemical smell. It offgassed to "odourless" way faster than their standard type. You will need to test their "dots" that attach these to the floor as well. This Fedora line does not hold up well with pets and does not look super durable, though some might prefer this carpet because of how fast it offgasses.

If you have conventional carpet in your house that is still offgassing, seal in the VOCs with Carpet Seal.

Commercial Grade

Commercial grade carpet is a lot harder to find in low-VOC. I have reviewed and sniffed a few of the ones that claim the lowest VOC levels.

Flor: Most of their carpets are commercial grade. They claim they have the lowest VOC levels in the industry as of 2017, though when probed for information on their VOC levels or any evidence to substantiate that claim, they did not have any. They have Green Label Plus which you can find almost anywhere now and is not a low level of VOC. However, when testing their carpet it did not have that tell-tale new carpet smell. The initial offgassing was as strong as other regular brands but it seemed less offensive (I know everyone is different here). But, what did impress me was that the sample offgassed way faster than other brands that have the tell-tale new carpet smell. A few weeks outside and it is fairly tolerable for a conventional carpet.

The other good option for commercial grade is wool. Though commercial companies are more reluctant to use wool because it is more expensive. The Godfrey Hirst wool commercial carpets  show test results of very low VOC levels. Though they do have that classic carpet smell and it does contain mothproofing (permethrin). Woolshire wool is also rated for commercial, I found it much more tolerable than Godfrey - it smells wooly but not like chemicals. It does have mothproofing in it. It smells similar to Hibernia brand. If I was picking a commercial brand I would consider Woolshire first and then Flor.

Some of Earth Weave's lines can be used in light commercial applications and those do not contain mothproofing or other chemical treatments. In a light commercial setting this is the greenest way to go.

Because carpet does collect dust, mould spores, pesticides, flame retardants and all types of contaminants and allergens that ride on dust, a HEPA vacuum like the Nilfisk is essential for cleaning.

Carpets with a conventional synthetic backing (but not Flor), can be glued down with AFM 3 in 1.

I have a separate post devoted to non-toxic area rugs.

iv. Terrazzo

Terrazzo is a little complex as there are different materials, resins and sealers involved. But there are systems that are 0-VOC and low-VOC.

v. Laminate

low VOC, extremely low formaldehyde laminate floor
Most laminates now are low-VOC. Look for brands that have certifications, there are many, but GreenGuard Gold is the best certification for laminate.

Most brands can easily meet the other certification levels, so it does not help you to distinguish between them. Many do not use formaldehyde as the adhesive (in fact I would be surprised to see one with formaldehyde as the main adhesive in the HDF core).

Make sure they are not made with MDF which is usually high in formaldehyde. Most now are made with an HDF backing.

Ideally, they have GreenGuard Gold Certification, as this is the strictest level of formaldehyde 0.0073 ppm, far below any of the other certification levels. This is background levels, there is as much formaldehyde in the outdoor air. This is not the laminate from years ago!

Swiss KronoHome Decorators Collection and Traffic Master meet GreenGuard Gold and I found them very low in offgassing. Since formaldehyde is one of the biggest risks with laminate flooring, this is the most important certification. A number of other brands have this certification as well. Here is my video review of brands you can buy at Home Depot, I was impressed.

Not all good brands have GreenGuard Gold, Pergo line does not use a formaldehyde glue, but they declined to say which glue they used and the SDS does not say. One sensitive client preferred the Pergo Outlast from Home Depot to the Home Decorators brand.

Brands sold at green supply stores like Eurostyle (by the large worldwide company Krono Flooring) were not able to say their actual formaldehyde or VOC levels, and only cited their certifications, and so they did not provide any information to distinguish themselves from the other brands.

This type of flooring can be floating - it doesn't require adhesive which is a bonus.

3. Light Green (Low-VOC)

i. Engineered Woods

engineered flooring low in VOCsJunkers, Wood Flooring International all meet EU emission standards. WD brand is one recommended by sensitive folks. The substrates can still be problematic. Many use phenol formaldehyde which offgasses relatively quickly. This may work for some but they are not in the same category as the formaldehyde-free versions above.

ii. Cork

best cork brands that are low in offgassing healthy and safe
Cork like wood, has a natural odour (terpenes). A resin is used to bind all the small pieces of cork together into flat pieces (I have seen polyurethane binders which I find to have strong offgassing that persists). In theory, you can make tiles or rolls without resin (they heat press them for some insulation) but this is not how cork flooring is made.

An adhesive is also required either to glue it down (and there are 0 VOC glues for this), or, in the floating floors the substrate is often problematic. It is finished with urethanes/acrylic which may be tolerable once cured.

I have tested Cali Bamboo cork which I found to be the best one. US Floors was the second best. NOVA and Cancork smelled very strong to me. Here is my Facebook post about the testing of these brands. These floors claim to be green but they offgassing is higher than I would go for and that's why they are in the light green category.

Some flooring that has a cork core and laminate on top can sometimes be referred to cork flooring even though it has a laminate or plastic top. Cali Bamboo Silverwood falls into this category, which is cork with a laminate/ceramic top, as well as Woodwise which has a PET plastic (not vinyl) engineered top layer.

iii. Bamboo

Requires resin or adhesives to hold the top layer pieces together, a substrate and a finish. However, there are many that are GreenGuard certified for low emissions. This wood is known to be problematic in that it can shrink, expand and do poorly with humidity/water/moisture/spills as well as really dry climates.

Cali Bamboo GeoCore is made on a limestone-based core which I found tolerable.

The other type that is very solid is the Ecofusion, which is not the typical engineered product it is 100% bamboo through and through (with the usual glues. I look at it in this flooring video here.

iv. Magnetic Ceramic Tiles

alternative to tiles with grout or glue
I tested Kablan's magnetic ceramic tiles and I found they did have a moderately strong smell (the magnetic backing components), though you may not be able to smell them once the floors is installed, as they are underneath. My video review of them here.

v. Luxury Vinyl Plank

is vinyl flooring low in offgassing and safe for the chemically sensitive
Luxury vinyl plank (LVP) is much more tolerable than people generally think. I know, most of us think vinyl is one of the worst options. It is low-VOC, and mostly phthalate-free now. But I do have concerns over small amounts of metals explained more below

Should you Consider Vinyl as a Safe Choice

This might be one of your first considerations for an RV, and can be considered if engineered and laminate floors don't work for you, or you are in the mild to moderately sensitive category.


I tested Armstrong and Cali Bamboo brands - both surprised me in how low the offgassing was. I also tried the brands you can find at Home Depot which I review here. Armstrong and Cali Bamboo are still my top choices.

Cali Bamboo has a limestone backing which is excellent in terms of health and safety (much preferred over vinyl and/or cork backing).

Cali discloses their testing and the VOC levels are extremely low. Here are their phthalate testing results (they are not phthalate-free). Use a floating floor instead of glue down when possible. You don't always have to go with the branded underlayment for all floors, but the Cali underlayment is very good.

Armstrong has three different thicknesses. The least thick one (called Good) as shown here, has the least offgassing however it's a glue down floor. "Better" and "Best" are thicker and are click together, slightly higher VOCs in my estimation than the thinnest option. I don't like the cork backing on the "Best" as the glues are higher in offgassing. All the Armstrong vinyl I have reviewed is phthalate-free.

Out of the Home Depot brands, Traffic Master was the thinnest one. Life Brand to me seemed to have the lowest offgassing of the Home Depot Brands, though the underlayment offgassing was strong to me. Home Decorators was similar to Traffic Master. All brands sold at Home Depot, Lowe's, and Lumber Liquidators are phthalate-free.

Double-check on all brands to make sure it's virgin (not recycled vinyl).

Phthalate-Free Vinyl Flooring and Replacement Plasticizers 

Phthalate-free brands are preferable - which most are now. If Phthalates (also known as ortho-phthalates) are not used, other plasticizers will be used instead.

Replacement plasticizers include DOTP (also called DEHT). Some may contain benzoate ester. (Source).

Toxic Metals in Vinyl Flooring

Organotins (a form of tin) can also be used in the top layer. Antimicrobials can be used, usually in the underlayment. I have seen various types including silver. EHN found the heavy metal cadmium recently in vinyl floors (probably recycled ones, they say).

It's important to avoid recycled vinyl. Lumber Liquidators and Floor & Decor banned recycled vinyl to avoid the associated toxic contaminants like metals and halogenated flame retardants.

Lead, cadmium, chromium, and mercury can be present and are only officially limited, as far as I have seen, by Floor and Decor. Though antimony, bromine, and lead have been virtually eliminated according to the latest study.

Cost Comparison of Green Flooring 2019 (US)

Wood $8-10/sq ft including installation

Polished concrete is $6-12 sq ft for residential

Stain and sealed concrete - materials $1/sq ft (unless you are pouring the concrete or have lots of prep)

Tiles are usually $8-10/sq ft but it depends on the tiles (tiles come in a wide range of costs) and prep of subfloor/installation difficulty

Kahrs Engineered - Materials $5-12/sq ft, labour $3-10/sq ft
Home Depot Brands engineered start at $3/ sq ft for materials

Marmoluem - Materials $4.50-5/sq ft, labour $1-4/sq ft

LVP - Cali bamboo - under $3.30-5/sq ft, labour about $3-4/ sq ft for click
          Armstrong starts at $1/ sq ft for materials
          Home Depot brands $1-3/sq ft

Laminate - Home Decorators Collection $1.30-2/sqft
                  Trafic Master $0.50-2/sq ft

Cork $8-10/sq ft including installation

Corinne Segura is a Building Biologist with 5 years of experience helping others create healthy homes.

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Non-Toxic & Natural Alternative Wall Systems

This post contains affiliate links to relevant books and products that I use and recommend. Upon purchase, I earn a small commission at no extra cost to you.

For individual help on choosing the best products and materials for you and your home, you can schedule a consultation with me here.

Drywall now has it's own dedicated post here: Guide to Non-Toxic Drywall Types and Brands.

Non-Toxic Wall Systems

The following are concrete and earth-based wall systems that do not offgas toxins and are suitable for the chemically sensitive. Something a little different from the standard timber frame, fiberglass and gypsum boards.
Pumicecrete Walls

A mix of pumice and concrete are poured into forms to create these non-toxic walls. They can be made load bearing with a concrete beam. Test pumice for radioactivity and for odours that it may have picked up prior to installation.

An interesting material making a comeback, HempCrete is blocks made of hemp and a lime-based binder. The blocks are used to form the walls and act as insulation. They are not load bearing so are used with a timber frame. HempCrete claims to not mould, but a natural fiber in a breathable wall is not something I would consider mould proof. Consult with an architect to make sure this is right for your climate.
Wood Insulated Concrete Forms

Forms are made of a mix of remineralised wood and concrete. Inside, rebar is used as reinforcement and then they are filled with concrete. Insulative fibers can be added or they can be filled with part concrete and part clay or a non-toxic insulation. Brands include Durisol(Nexcem) and Faswall. Faswall currently the only brand available in the US (2017).
Aerated Autoclaved Concrete (AAC)

Concrete based blocks made from quartz, lime or cement, and aluminum powder. Test thinset mortar for sensitivity. Hebel is one brand in the US. It's not approved in California (2017).
Insulated Concrete Form ICF

Nudura blocks (US and Canada) and Fox Block (US and Canada) are the most popular brands right now. ICF could mean different types of foam with concrete fill, but typically it is EPS. See my post on Insulation for a detailed review of EPS. Nadura has a dye. Both have flame retardants.

Is Concrete Non-Toxic?

Portland Cement is non-toxic. It should be confirmed that it is free of admixtures such as air 
entrainment and water reducing agents, accelerants and retardants, and super plasticizers. 

Ceramic Cement (Magnesium Cement) is also generally a non-toxic option.

 Which Concrete Aggregates are Chemical-Free?

Natural non-toxic mineral aggregates should be used. Toxic aggregates include crushed brick, crushed 
sandstone, concrete slag, fly ash, cinder, and volcanic materials other than pumice. (Source: Prescriptions for a Healthy House).

3. Natural Building: Earth-Based Walls

Cob, Adobe, Light Clay-Straw, and Straw Bale and Rammed Earth

Adobe house from
These are all different types of walls made of clay, straw, and sand. But instead of giving a comprehensive overview I will comment briefly on the suitability of these building materials for the chemically sensitive.

Houses made of all natural materials feel great to be in and there is no need to worry about any offgassing.

However there are precautions that should be taken to avoid mould. These types of builings might be best suited to dry climates so that there is no chance of mould forming. Some people seem to be doing very well in adobe houses in the south-western US.

If straw is used in the walls it should be carefully sourced to be free of mould and pesticides. When building with cob, adobe or light clay straw there needs to be a dependable dry season of three months for the walls to dry out properly.

They are particularly suited to be heated with wood stoves as that dries out the walls well in the rainy and damp seasons (source: Econest).

An above-grade stem wall and proper drainage around the house is also very important to keep the walls from getting damp.

I'm hearing some bad stories of mould forming on cob and straw bale homes in cold climates, this is likely due to high humidity inside in the winter.

Rammed Earth from

Another natural wall system worth mentioning in a little more detail, Rammed Earth, uses sand, gravel and clay and has had an interesting development recently. Foam has been added for insulation and steel for support, and 5-10% cement is added to the clay mixture. It's called Stabilized Insulated Rammed Earth.

Water does not penetrate the walls, however concrete, especially when not climate controlled is extremely prone to mustiness.

Corinne Segura is a Building Biologist with 5 years of experience helping others create healthy homes.

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Simple Insulated Shelter for MCS and Mold Avoidance

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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. 

The 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 videos).

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: