The Least Toxic Wood Varnish?
I tested all of the “eco” or, healthy low VOC, floor finishes. I was looking first at the odor and VOC levels as the main comparison for those sensitive to chemicals.
I take a look at the ingredients and claims, but that can only tell us so much.
I also wanted to see what the finishes looked like and how much they changed the color of the wood.
Each varnish was applied in three coats to oak flooring pieces. Though I didn’t sand the wood as much as you would for floors in a house, I was still able to get some comparison on durability. In reality, it takes years to see the full picture of how they hold up.
Which one is Ultimately the Best?
One of the main complaints of these “green” clear floor finishes is that the lowest odor ones are not always the most durable. That is somewhat true.
I would use most of the finishes on this list but it will be up to each person to choose which one ultimately is the best for them and their project.
For Furniture and Woodwork too
The original focus was on floors but many of these brands can be used on furniture, wainscotting, and other interior woodwork. I mention those in the post as well.
Lowest Odor When Wet
Earthpaint Aqualine and Easy 1 K.
Close second place – BioShield Aqua Resin
Lowest Odor at 24 Hours
BioShield Aqua Resin
Most Invisible Look
BioShield Aqua Resin, followed by AFM Poly BP
No obvious choice… more below.
This post is not sponsored. I paid for all of the samples and supplies.
At the time of writing, a couple of the companies – ECOS and AFM – have affiliate programs. Upon purchase, I earn a small commission at no extra cost to you.
By Odor Level:
When wet: From most mild to least – Aqualine and Easy 1 K, Biosheild Aqua Resin, ECOS, AFM, then Vermeister.
At 24 Hours – they were mostly all at a similar odor level at 24 hours, though I did find Biosheild Aqua Resin had taken first place at 24 hours.
48 hours – at my level of sensitivity I could not really pick up much at 48 hours off any of the finishes. Some had just a slight offgassing and some like Biosheild and Nanotech were odorless to me.
There are folks who are more sensitive and more reactive than me. Please get samples to see which ones are best for you.
There was no clear winner in my durability test. This is what I threw at them:
- Water – left on until it dried, all passed though 1K and NanoTech have some very slight water circles
- Red wine vinegar, all passed
- Quats all passed
- Wet rag left on them, all passed
- Urine for 20 seconds, all passed
- Urine for a couple of hours, all passed but a very very slight marring on Poly BP
- Tumeric in water for 30 seconds, all were somewhat affected. The most affected were Aqua Resin, Nanotech, then ECOS, Poly BP was only ever so slightly affected. Vermeister and 1 K held up quite well.
- Boiling water they all passed (a tablespoon)
- Alcohol tincture, whiskey, and red wine – 1 K and ECOS didn’t hold up as well as the others, Poly BP also had some marks
- Smashed in blueberry sauce, all passed except Poly BP
1. ECOS Paints
ECOS wood finishes (like their paints) are 100% acrylic. Most floor finishes are polyurethane.
You can see a full ingredient list for each product on their website. This is the most transparent of all the brands as all ingredients are listed clearly.
While these can be used on floors, in my experience this is not the most durable option. It can also be used on other woodwork around the house. I used it in my tiny house on my kitchen cart and was very happy with it.
Like with all coatings listed here, 3 coats are recommended on floors.
- Interior Satin Clear – only slightly milder than AFM (not that different). At 48 hours there is still a slight sweet smell.
- ECOS Air Purifying Varnish (APV) this was stronger when wet than regular ECOS satin, but better than regular satin at 48 hours. At 48 hours could not pick up anything.
- ECOS Wood Conditioner – is more mild than the varnishes, but not totally benign.
- ECOS Tinted Varnish – a little milder than the clear varnish (maybe the pigments are diluting it a little).
- ECOS Exterior Satin – not that different from the interior finish. The exterior might even be milder!
- ECOS Interior Satin is $89.95 a gallon and covers 500 sq ft (one coat)
- ECOA APV is $99.95 a gallon
- ECOS Tinted Varnish is $93.95 a gallon
Where to Buy:
- Through the ECOS Paints website.
2. AFM Safecoat
- Acrylacq, Satin – much more tolerable when wet compared to Poly BP. This sealant is not used on floors but it’s a great durable sealer for furniture, cabinets and other interior woodwork. Ingredients include: Acrylic polymer, Dipropylene Glycol Methyl Ether, Water, Amorphous Fumed Silica.
- AFM Safecoat Polyureseal BP, Satin – the strongest one when wet. This is AFM’s main floor finish though it can also be used on furniture. It smelled almost like an acrylic to me, although it’s mainly a polyurethane. Like all finishes, three coats are recommended. I like this brand because it’s a tried and true finish that is quite durable.
- Ingredients include: Polyurethane Aqueous Dispersion, Dipropylene glycol methyl ether, Water, Acrylic polymer
- AFM SafeCoat DuroTone, is AFM’s wood stain if you want to alter the color of the wood. Acralaq or Poly BP (among others) are used as a top coat over it. The Cognac which I tested, had a bit of an unexpected smell. I thought it would be milder than it was, but it is milder than the varnishes. I could hardly pick up an odor at 48 hours.
- Acrylacq is $85.90 a gallon and covers approx 350 sq ft (one coat)
- Polyureseal BP is $99.90 a gallon and covers approx 450 sq ft (one coat)
- Durotone is $53-72 a gallon and covers approx 450 sq ft (one coat)
Where to Buy:
- Green Design Center for sure. Talk to Andy who is an expert on AFM products and he can give you or your contractor advice on the application.
BioShield makes two varnishes. Their floor finish, Aqua Resin Floor Finish, is polyurethane-based. The ingredients are listed as alcohol, anti-skinning agent, dispersion of polyurethane in water, micro wax, silicic acid, and silicone. It can be used on wood, concrete, and cork, as well as wooden doors, molding, work surfaces, tables, stairs, and furniture.
Their Aqua Resin Stain Finish, which is even milder, can be used on children’s cribs, swing sets, windows, doors, and wood furniture (not floors). The ingredients are alcohol ester, earth pigments, preservative, silica, surfactant, and water.
- Aqua Resin Floor Finish, Clear. It was very mild when wet. It was preferable in my view to Vermiester and ECOS. It was the best of all the options VOC-wise at 24 hours. At 48 hours I could not pick up any offgassing. Three coats are recommended.
- Although it was slightly less durable than the others, the extremely sensitive will surely want to consider this brand for the very low offgassing.
- Aqua Resin Floor Finish is $189 for 1.32 gallons which covers 700 – 800 sq ft (one coat)
- Aqua Resin Stain Finish is $92 for 1.32 gallons
Where to Buy:
- Green Building Supply, especially if you want to get samples. You can also order directly through the company.
Vermeister Zero VOC is a polyurethane that claims to be 0-VOC as you can tell from the name. I tested the Satin without the booster. The MSDS does list ammonia (which is an exempt VOC).
The booster part of a polyurethane is always higher in odor and VOCs.
It was slightly stronger in odor than AFM Poly BP when wet but they were not that different. I don’t see how this product could be 0-VOC. AFM Poly BP does declare their VOC levels at 100g/l.
Based on this perceived discrepancy in labeling between the brands, I would assume that AFM is more transparent and more accurate. Though they could be measuring the VOCs at different times to get those results. Also AFM does not have ammonia, the exempt VOC.
I could hardly pick up offgassing at 48 hours.
Synthetic polyurethane is the standard for floor finishes. In some ways, this was the most durable of all the options here (though not by much), and probably the most conventional, especially if you add the booster.
- Vermeister is $129 a gallon which covers 300 – 500 sq ft (one coat)
Where to Buy:
5. Vermont Natural Coatings
Vermont Natural Coatings is a bio-based polyurethane. This means part of the polyurethane is derived from whey. They claim that the co-binders and solvents typically found in conventional wood finishes and polyurethane coatings are replaced by naturally derived ingredients.
PolyWhey Floor Finish is a good option for floors, bars, tabletops and other large horizontal surfaces. If your project involves vertical surfaces (like bookcases or chair legs), they recommend using the Furniture Finish.
Polywhey floor finish can be applied over a previous oil-based floor finish.
(PS their exterior PolyWhey is also known to be the most durable low VOC water-based exterior finish).
- Hydro Lacquer Reactive Sealer with PolyWhey – this gives the look of an oil finish. It can be used on furniture and floors.
- PolyWhey Floor Finish – their general bio polyurethane floor finish.
- All-in-One Stain & Finish – their Polywhey with a stain included, this is not recommended for floors.
- Hydro Lacquer with PolyWhey is $82.75 a gallon
- PolyWhey Floor Finish and the Stain & Finish are both $77 a gallon which cover 500 – 600 sq ft (one coat)
Where to Buy:
- The floor finishes can be purchased through their website. Their furniture finish can be purchased on Amazon.
Earthpaint’s finishes ranked among the most tolerable in odor and offgassing.
The Aqualine does not have polyurethane in it, this is a 100% acrylic floor finish. There are no exempt VOCs or solvents.
The Easy Safe 1 K finish is a commercial finish described as a nano acrylic/polyurethane mix. It’s made for wood floors, bar tops, gyms, countertops, restaurant tables, and boats.
Their NanoTech is a wood floor and concrete finish made from nano-sized liquid acrylic resin. It can also be used to block offgassing from a previously laid finish (including many oil-based finishs). It can be used on the exterior as well.
- NanoTech – can’t pick up odor at 48 hours
- Easy Safe 1K Floor Finish – this one I can still pick up at 48 hours – though I found it significantly better than Vermeister, Poly BP. Better than ECOS when wet. Slightly better than Biosheild when wet.
- Aqualine, satin – This was the best of the Earthpaint finishes when wet. It was hard to judge because it arrived partially solidified. It does seem milder than their 1 K, but not sure if that is accurate. Still, I barely could pick up any odor at 48 hours.
- NanoTech in clear is $98.09 a gallon which covers about 400 – 500 sq ft (one coat)
- Aqualine and Easy Safe 1K in clear are both $139.98 a gallon covering 500 – 600 sq ft, and 400 – 600 sq ft respectively (one coat)
Where to Buy:
- Buy it directly through the Earthpaint website.
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