This post is for climate conscious consumers who want to take a deep dive into the certifications, and manufacturing practices, that matter most for finding ethical hardwood flooring.
There are a few key things to consider when choosing ethical hardwood flooring. First, is the wood sourced sustainably?
If so, you’re likely to see an FSC certified logo somewhere on the product. Or, alternatively, you might see an EMAS certificate.
Without these, it’s likely that the wood comes from clear cut forests that are poorly managed, to the detriment of the environment.
FSC and EMAS certification
FSC stands for Forest Stewardship Council and certification by this international non-profit organization is the gold standard for the US Green Building Council‘s LEED (Leadership in Energy and Environmental Design) projects. FSC encompasses environmental, economic, and social principles and the labelling body has a robust network of independent certification worldwide. FSC looks at where and how wood is sourced, by whom and under what conditions.
To become FSC-certified, suppliers must meet 10 principles and 57 criteria, including wildlife protection and support of unionized workers.
Don’t just look for an FSC logo and call it a day though. The presence of an FSC logo on a company’s website or a handful of products doesn’t guarantee that the entire product you’re looking at is FSC certified.
Greenwashing is rife in the flooring industry. Some flooring that is labelled FSC certified only has a small amount of certified sustainably sourced wood present (usually in the top layer). What you want is a guarantee that 100% of the wood is FSC certified. This means looking for a label saying “100% FSC”. Examples of greenwashing are where a product is labelled “FSC Mixed Sources” or “made with FSC certified wood”.
If you have the physical product in front of you when buying, the box itself should have an FSC logo. In addition, you should be able to see a COC (Chain of Custody) number for the vendor or manufacturer, and this will also appear as a line item on your receipt.
As for EMAS, this is the Eco-Management and Audit Scheme developed by the European Commission. It is a voluntary certification that can be used by European companies and focuses on continuous improvement of environmental parameters, transparent reporting, and independent certification by external experts. As such, American companies are ineligible for EMAS unless they also have a significant European center of operations. If a product has no FSC or EMAS certification, look elsewhere.
Other certifications for hardwood flooring
FSC and EMAS aren’t the only things to look out for when searching for eco-friendly flooring. Hardwood floors can also be certified by Greenguard Gold for low VOC emissions and by Indoor Air Advantage Gold, though neither are especially strict indoor air quality emission standards. Floorscore lays out slightly more robust air quality requirements.
The best way to choose a truly green product that won’t adversely affect indoor air quality, though, is to look for hardwood that is certified to CARB2 (in the U.S.) or E0 (in Europe). These are the strictest levels for air quality impacts, especially for emissions of urea formaldehyde. The EPA standard is 0.75 ppm, the European standard is 0.07, and the California Air Resources Board 2012 standard (CARB2) is 0.05. In general, though, if a product emits formaldehyde at over 0.01 ppm (parts per million), choose something else.
You might also want to look for products that qualify for LEED EQ4.4. This pertains to composite wood and agrifiber products such as engineered wood that contain no added urea-formaldehyde resins.
Some flooring also carries Sustainable Forestry Initiative (SFI) certification. SFI is another non-profit organization working to protect forests, although it was established by timber and paper companies. Perhaps unsurprisingly, SFI standards aren’t as rigorous as those of FSC or EMAS. SFI certification does offer assurance that wood isn’t from old-growth forests though.
Finally, you might see an American Tree Farm System (ATFS) certification on some flooring products. ATFS is also a non-profit organization and works to certify sustainably managed forests, i.e., where for every tree harvested, more trees are planted.
Formaldehyde-free? Not so fast
For regular readers of LeafScore.com, you’ll know that we rather dislike formaldehyde, a volatile organic compound (VOC). After all, this chemical is a known carcinogen and is very bad news for infants, pets, and other vulnerable family members. When it comes to flooring, though, you’re just not going to find a product that’s formaldehyde-free.
Why? Because wood naturally contains some formaldehyde.
The good news is that formaldehyde is mostly bound inside solid wood, so it doesn’t off-gas to any great extent, unless it is subjected to high heat. The trouble, then, seems to be with engineered (composite) hardwood flooring that has been treated with urea formaldehyde or that is finished or stuck down with glue containing urea formaldehyde. You can mostly avoid these if you stick to products that are CARB2 or E0 certified. However, again, things are more complicated than that.
I spoke with Danny Harrington of Galleher about sustainable flooring options and got a crash course in floorboard pressing methods and their impacts on formaldehyde emissions. Danny used to run EcoTimber, served on the US Green Building Council’s Technical Advisory Committee for Certified Wood and on the Sierra Club’s Forest Certification Committee, and served as an adviser to the CARB when they originally developed their standards.
Danny told me of a case where switching from a urea-formaldehyde glue to a formaldehyde-free glue for bamboo flooring actually increased formaldehyde emissions by 33%. The reason being that urea-formaldehyde glues are all cold-press glues, meaning that heat isn’t used to activate the glue. In contrast, urea-formaldehyde glues do require a hot press for activation, and this heat not only removes most of the formaldehyde in the glue but also from the bamboo. With the cold-press method, none of the naturally occurring formaldehyde was flashed off from the bamboo, meaning what was left was higher than after the hot-press, urea-formaldehyde glue process.
As Danny puts it, in the end, “the only thing that matters are the actual emissions from the finished product, not what type of adhesive was used, because there are many other variables at work.”
Again, solid wood doesn’t typically emit much formaldehyde. The process of milling wood and creating composite wood flooring, however, can break down the polysaccharides in the wood and release benzaldehyde, formaldehyde, acetaldehyde, 2–propenal, butanal, and butanone.
Eco-friendly finishes for hardwood floors
Flooring is a perfect example of how ‘natural’ may not actually be the most eco-friendly or non-toxic overall. Hardwood flooring that hasn’t been finished (coated) in the factory will become damaged much faster than flooring with a robust UV-cured factory finish, for instance. In some cases, this may necessitate replacing the flooring, which obviously isn’t sustainable.
Unfinished or naturally finished wood products will also require you to finish the flooring at home. And this is where we run into a whole heap of trouble with hardwood flooring maintenance products and off-gassing.
Carnauba wax or beeswax might seem to be the healthiest choices for a floor finish, but the opposite may be true. These oil or wax products almost always require solvents to get the product to dry properly. You will also have to maintain most oil and wax finishes with solvent-based products.
And, worryingly, the U.S. standard for these products is not as robust as in Europe, meaning you may be misled by natural oil finishes labeled ‘Zero-VOC’ in the U.S. that don’t qualify for zero-VOC labels in Europe.
How can this be? In the U.S., companies can sell products as ‘Zero-VOC’ even if they use ‘VOC-exempt’ solvents such as isocyanate. These exempt solvents are single component solvents that don’t contribute to ground level smog, and the EPA and SCAQMD maintains VOC-exempt lists. In Europe, the list of toxic chemicals is much longer and isocyanate is classed as a VOC.
I’ve written about the harmful effects of isocyanate before and am appalled that this wouldn’t need to be included in the total VOC calculation for a product in America.
As I always say at LeafScore, what’s actually in a product is what matters, not what a manufacturer claims isn’t in it.
Factory finish options
What to do about flooring finishes then?
Well, despite appearing the better option at first, it seems best to avoid unfinished hardwood products and those finished just with beeswax or carnauba. In addition to potentially exposing yourself to higher levels of toxic chemicals in the home, you’ll probably need to refinish the floors more frequently, re-exposing yourself and, arguably, using more resources overall as your floor won’t last as long as one with a UV-cured factory finish.
UV-cured finishes do not contain any solvents, are dry before the flooring reaches your home, and can be cleaned with water-based cleaners free of toxic chemicals. Most newer polyurethane finishes do not contain solvents and don’t off-gas. So, while these are still fossil fuel derived, they’re far better for indoor air quality and mean fewer toxic chemicals are involved in the entire lifecycle of the flooring.
Be aware, though, that some manufacturers continue to use oil-based polyurethanes applied with solvents. These chemicals can off-gas for weeks or months and are associated with myriad health issues. Avoid these if you can, especially if you have children, pets, or vulnerable adults in the home or who visit regularly. The best way to avoid these is still to look for products that are CARB2 or E0 compliant.
Finally, not all finishes can be used with all flooring products. If you’re unsure, ask the retailer or manufacturer before buying and applying (and potentially ruining your floor!).
Final thoughts on how to choose sustainable hardwood flooring
Unfortunately, even if you read the MSDS (Material Safety Data Sheet) for a product, you might not be able to detect if there are any toxic chemicals in the product. This is because manufacturers only have to list known hazards present at more than 1% of the total volume.
Thinking about the bulkiness of flooring and the fact that so few chemicals have actually been robustly tested for impacts on human health, this isn’t always the best guide when it comes to safety. Your best bet is to ask exactly what is in a product and go with adhesives and finishes that are legitimately zero VOC and free from isocyanine.
As well as looking for CARB2 and/or E0 certifications, note that water-based finishes are not necessarily zero VOC. Many still contain solvents other than water, as well as other chemicals that off-gas, so don’t get fooled by this verbiage.
Finally, in addition to choosing FSC Certified wood, consider where the wood is coming from. If you can, choose wood that comes from local forests and is milled nearby, or choose locally reclaimed or salvaged wood. This will help to keep transport associated carbon emissions low, making for a more sustainable flooring choice all round.