Dirty Details
Formaldehyde
Composite wood flooring products like engineered hardwood, bamboo and laminate are made by fusing wood layers together with glues and resins. But, these glues are often made with formaldehyde, a known human carcinogen and serious home air pollutant.
Formaldehyde-based glues typically come in one of two types: urea or phenol. Urea-formaldehyde glues are of greatest concern because they release formaldehyde throughout the life of the wood, whereas phenol-formaldehyde glues emit 90 percent less formaldehyde.
Because of formaldehyde’s health risks, we recommend you avoid composite wood products as much as possible. But if you do decide to buy composite wood flooring, there are a few ways to minimize your exposure risks:
- First, look for products labeled with one of the following standards developed by California’s Air Resources Board, which sets voluntary standards for formaldehyde emissions from composite wood products. These are the strictest standards on the market for formaldehyde use and emissions:- NAF, which means the product has no added formaldehyde. This is the highest standard and is best for your indoor air.- ULEF, or ultra-low emitting formaldehyde, means the product’s glues and resins contain formaldehyde, but the product emits formaldehyde fumes at ultra-low levels, as determined by the board.
- The next best options are products labeled as NAUF, or no added urea formaldehyde. This standard, created by the U.S. Green Building Council, indicates that the product does not use urea formaldehyde, which releases formaldehyde throughout the life of the product. Instead, NAUF products use phenol-based glues, which emit 90 percent less formaldehyde.
- If you cannot find flooring that meets the above standards, look for products certified by the California Air Resources Board to meet basic safety standards for formaldehyde emissions. These products will be labeled as California Phase 2 Compliant.A new national standard for low formaldehyde emissions in pressed wood products mirrors California Phase 2 standards. Products that meet this standard will be labeled as TSCA Title VI Compliant and may be available as early as 2018.
Sustainability
In addition to a product’s impact on your health, consider sustainability when choosing flooring. This is especially true when using wood and bamboo products because poorly managed logging practices can have major environmental impacts, including deforestation, loss of habitat, extinction of plant and animal species, soil erosion and water pollution.
Because of this, we recommend choosing wood and bamboo products that are certified by the FSC, which is the best indication of sustainably harvested wood. Keep in mind that not all products from a certified company may be FSC certified, so be sure to read the label of the wood or bamboo you are buying.
Recommended Flooring
We recommend the use of solid surface flooring instead of carpet whenever possible. This will help you avoid the chemical and allergen air pollution commonly associated with carpeting.
Solid Wood
Suitable for bedrooms and living areas
Hardwoods like oak and maple take longer to grow, but are generally more resistant to dents and damage than softwoods like pine and birch, which grow faster and are more easily replenished. Hardwood planks are typically more expensive for the raw material, though costs to install and finish the wood should be the same.
Verify that the wood species you choose is not endangered. The U.K. branch of the nonprofit Friends of the Earth maintains a Good Wood Guide with more information on different types of timber.
Note the following when using solid wood flooring:
- Select products that are FSC certified, as this indicates that the wood was sustainably harvested; or check green building retailers for recycled or salvaged wood that has not been previously painted, glued or coated (ask for documentation of the wood’s source);
- Look for wood that has been harvested and milled locally if possible, to reduce the product’s carbon footprint;
- Install wood flooring with nails, not glue;
- Seal with a water-based, Green Seal 11-certified finish; or choose pre-finished floors, instead of those finished on-site, to avoid exposure to fumes from stains and finishes.
- Water damage is a common problem with solid wood flooring, so it is not recommended for bathrooms, kitchens or laundry rooms.
Natural Linoleum
Suitable for most rooms, including bathrooms and kitchens
Linoleum is an environmentally friendly, affordable flooring option. It is both water-resistant and resilient, meaning it has a little give, which makes it a good choice for kitchens and bathrooms.
Natural linoleum is a mixture of linseed oil, pine resin, wood flour, cork flour, limestone and pigments pressed together onto a jute backing. This low-maintenance option can be installed on wood or concrete subfloor, and typically needs just a coat of natural wax (beeswax and linseed oil) for protection and care. With proper upkeep, these floors should last for decades.
Note the following when using linoleum flooring:
- Choose interlocking linoleum tiles that can be installed easily without the need for adhesives, or sheet linoleum with low-VOC, solvent-free adhesives;
- “Linoleum” is sometimes used generically to refer to vinyl flooring, so verify that you have chosen natural linoleum made from linseed oil;
Dirt can stain or mar the finish, so regular vacuuming or damp mopping is important. Never leave the floor wet and clean up spills promptly because water can damage the surface, as can harsh cleaners.
Ceramic, Porcelain and Glass Tile
Suitable for most rooms, including bathrooms and kitchens
Ceramic, porcelain and glass tiles are durable choices for solid-surface flooring and are good for rooms with a lot of moisture, like bathrooms and kitchens. For a sustainable choice, look for glass tiles made from recycled materials. We don’t recommend stone tile, however, as it is energy intensive to mine, handle and transport.
Note the following when using tile flooring:
- Buy tiles made in the U.S. to avoid lead glaze;
- Use low-VOC or Greenguard Gold-certified cement backer board;
- Use water-based adhesive, cement thin set (also known as mortar) to set tiles;
- Use cement-based grout, which does not emit harmful VOCs;
- Use low-VOC sealant to protect the grout and tile; and
- Cut or grind tiles outside to reduce inhalation of dust.
Use with Care
Follow our guidelines below if you are interested in using cork, engineered hardwood or bamboo flooring in your home. We can recommend these flooring products only when they are selected carefully, using our parameters for avoiding products made with harmful chemicals or those with negative environmental impacts.
Cork
Suitable for most rooms, including bathrooms and kitchens
Cork flooring is typically suitable for kitchens and bathrooms due to its mold- and moisture- resistant properties. It is also naturally fire retardant, does not adsorb dust, is warm underfoot and provides cushion when standing. It is a natural product made from the bark of cork oak trees, and because harvesting does not damage the tree, it is highly renewable. Cork is as durable as hardwood and can be placed over plywood, concrete or existing flooring as tiles or sheets. And at the end of its life, cork can be composted or recycled.
However, the composition of cork floors can vary widely and may contain harmful binders.
Therefore, when choosing cork flooring, verify that it is:- Not a cork-vinyl composite with a PVC backing;- Not made with crumb rubber;- Not made with carcinogenic isocyanate or formaldehyde binders; and- Recommended for the parts of the home where it will be used (e.g., bathrooms).
Engineered Hardwood
Suitable for bedrooms and living areas
Engineered hardwood flooring is made up of a top layer of real hardwood veneer adhered to a core of plywood or other wood material. The advantage of engineered hardwood is that it comes pre-finished, making it less labor-intensive to install on-site, and it can be sanded and refinished at least once. The disadvantage is that the glues and wood composite materials may contain formaldehyde.
Therefore, when choosing engineered hardwood flooring, make sure to carefully select a product that meets the following criteria:
- FSC certified;
- formaldehyde-free glues; and
- low-VOC or Green Seal 11-certified finish.
Bamboo
Bamboo is a rapidly growing, renewable material that can be harvested every three to five years. Some types of bamboo are harder than oak and can last 30 to 50 years. But some bamboo harvesting practices are unsustainable and contribute to deforestation, and few bamboo products are currently FSC certified.
Additionally, bamboo flooring is composed of glued strips, and until recently, all bamboo floors contained formaldehyde-based glues. Some replacement glues can also contain isocyanates, which can cause respiratory irritation and sensitization that can result in severe asthma.
If, after considering other alternatives, you still have your heart set on bamboo flooring, make sure to carefully select a product that meets the following criteria:
- FSC certified;
- formaldehyde-free glues; and
- low-VOC or Green Seal 11-certified finish.
Not Recommended
Vinyl Flooring
Even though it’s popular and easy to install, vinyl is probably the worst flooring choice in terms of health, sustainability and production. It is a non-renewable material made from petroleum-based chemicals. Vinyl is made from PVC, or polyvinyl chloride, plastic, which produces toxic chemicals during manufacturing like dioxin, a carcinogen and reproductive toxicant.
Most vinyl flooring contains multiple harmful chemicals, including the same phthalates that have been banned from children’s toys. Phthalates can off-gas from building materials for years after installation. Phthalates are linked to birth defects and can disrupt hormones.
Additionally, be aware that many older vinyl floors contain asbestos. If you’re removing old vinyl, it is best to assume asbestos is present and consult a licensed contractor for assistance. Asbestos is a known carcinogen linked to lung cancer and mesothelioma.
Laminate Flooring
Laminate flooring products are made using a plasticized “picture” or image of wood glued to fiberboard, and as such, cannot be sanded and refinished. Recently, laminate flooring has been in the spotlight for emitting significant levels of formaldehyde, which is in the glues used to bond together the layers of pressed-wood laminate and the adhesives used for installation. Formaldehyde has been classified as a known human carcinogen, with no safe exposure level, and has been linked to numerous other health consequences from short-term exposures, such as eye and throat irritation, headaches and nausea.
