The following is an excerpt from Green From the Ground Up by David Johnston and Scott Gibson (Taunton Press, 2008). Begin with eco-friendly flooring, and move through this detailed guide for sustainable, healthy and energy-efficient home construction. This excerpt comes from Chapter 15, “Interior Finishes.”
There is a wide variety of eco-friendly flooring in the marketplace today. What makes flooring green? Here, many factors come together: durability, non-toxicity, renewable sourcing and transportation. The challenge is to determine which of these qualities are most important and how they reflect aesthetically. No product has everything, so it often amounts to comparing apples to oranges and making what seems like the best eco-friendly flooring choice.
Two general considerations for green flooring are its thermal mass and its compatibility with radiant-floor heat, if that’s the kind of heating system you have. Some sustainable flooring options, such as ceramic tile or concrete, are also good heat conductors, making them smart choices over radiant floors. Their thermal mass, higher than that of wood, complements passive solar design. Other products, such as certain kinds of wood, may not be appropriate for radiant-floor systems because of the risk of warping or splitting. Ask your supplier for the manufacturer’s recommendation before installing any of the following eco-friendly flooring options.
Finished Concrete Floors
When used as the finish floor, concrete containing high fly-ash content serves several as a multipurpose green flooring option. For one, it saves the expense of installing another flooring material, like wood or carpet. It also makes use of an industrial by-product, a decided eco-friendly flooring advantage. And concrete, unlike carpet, doesn’t harbor allergens, dust, and mold so it contributes to high indoor air quality.
A variety of finishing techniques can also produce dazzling visual results. Pigments applied to concrete as it cures, or acid-based pigments applied to concrete once it has set, can produce beautiful surfaces that look at home even in formal living spaces. Choose the right contractor and you’ll get concrete that becomes a two-dimensional sculpture on the floor. The trick is to look for an experienced installer, not necessarily someone who specializes in sidewalks and driveways and is trying to learn something new.
Linoleum and Vinyl Floors
Many people refer to sheet vinyl flooring as “linoleum,” a natural mistake. After all, linoleum was widely used until vinyl gradually shouldered it aside. But that’s changing, and linoleum is once again available. It makes a better green flooring choice than vinyl because it’s manufactured with less toxic materials.
While preferable to vinyl from a chemical standpoint, linoleum doesn’t have the same protective surface and must be polished occasionally to resist stains. Manufacturers recommend it be installed professionally. Be prepared for an odor from the linseed oil that off-gasses an aldehyde, which is not toxic for most people and will dissipate.
Vinyl flooring is very popular, but from a green standpoint it’s a product to avoid. Plasticizers called phthalates used to make PVC soft are a health hazard, especially in nurseries and play spaces where children will come in to close contact with the material. Recycled-content vinyl flooring is better than virgin material, but with so many other flooring choices available it doesn’t make sense to choose this one.
Bamboo is a rapidly renewable resource, making it a sustainable flooring option and also a durable flooring material. Bamboo matures in 3 to 5 years, versus the 40 to 60 years that oak or cherry need to mature to flooring quality. Bamboo flooring comes in two grain patterns—flat sawn or vertical grain—and typically with either a blond or caramelized finish.
There are a few caveats. Of the thousand or so varieties of bamboo, only a few are appropriate for flooring. Of those few, some are better than others in dry climates. When inappropriate species are cut and milled into bamboo flooring, it can result in cupping, shrinking or delaminating. The old adage “you get what you pay for” really applies to bamboo these days. When you see newspaper ads for cheap bamboo flooring, run the other way. Go with a company like Plyboo or Timbergrass, a supplier that has been in the business for over a decade and offers high-quality bamboo and eco-friendly flooring.
Sustainable Wood Floors
Available in solid wood and as engineered, prefinished varieties, wood flooring certified by the Forest Stewardship Council (FSC) is available across the country. The volume of certified wood flooring is increasing every year as more landowners get their wood lots certified and distribution improves. A growing number of exotic species are coming into the market from South America and Asia where certification is catching on as a way to improve market share.
Be aware that some certified engineered flooring contain urea-formaldehyde as the internal adhesive, with only the wear layer (4 to 6 millimeters thick) actually made of certified materials. Core materials may come from any number of other species. Other brands, however, are made with formaldehyde-free adhesives and are definitely preferable (EcoTimber is one company selling these green flooring products). To find out what you’re buying, you’ll have to ask the supplier for details. Companies that produce formaldehyde-free versions, however, are likely to make a point of it.
Cork flooring has become synonymous with green interiors. It is beautiful and has natural anti-bacterial qualities, is soft underfoot, is made from recycled materials, and comes from a renewable source. Cork flooring is typically made from the waste cork left over after bottle stoppers are manufactured. It has become so popular that it is sometimes made from raw cork. Cork comes from the cork oak native to Spain and Portugal. The “corks” are punched out of the sheet and the rest is ground and turned into flooring. The only downside is that cork trees grow only in a limited geographical area in the Mediterranean. All attempts to create cork plantations in other parts of the world, like California, have failed. So it is a limited resource for the future.
Carpeting for a green home should be made of natural materials, such as wool or sisal with jute backing. Fibers are woven into the backing or bonded with real rubber — avoid carpeting made with styrene-butadiene latex binder, an indoor air pollutant. Although natural wool sounds great from a green standpoint, its desirability depends on where the wool comes from. Domestic wool is fine, but if the wool is imported from Iceland or New Zealand it has probably been fumigated with a USDA-required insecticide that is off the charts in terms of toxicity.
Wall-to-wall carpet is an anathema to good indoor air quality. Not only does it off-gas itself (many carpets introduce over 100 chemicals into the home) but it collects dust, dander, and chemicals that are tracked in from outdoors. Its fibers absorb gases from other products. The Carpet and Rug Institute has worked with the EPA for a decade to create the Green Label program. This involves testing random samples off the production line for VOC emissions. They have recently introduced the Green Label Plus program that is stricter about emissions. The commercial carpet industry has been more aggressive in conforming to this new certification but always ask before ordering whether the carpet meets the program requirements.
A great alternative to conventional residential carpets it to use commercial carpets from Interface or Collins and Aikman. They have a lower pile and tighter weave and are designed for long-term use. InterfaceFlor™ is a new residential carpet tile product that uses recycled-content fibers and can be lifted and replaced if a square is stained.
Tiles make durable and attractive flooring that’s easy to install and doesn’t come with a learning curve like some green products. Most tiles are very durable; a key green consideration is whether they contain recycled content. As with many products, sourcing is an issue. Look for local, then regional, and finally domestic sources.
The best and greenest way to install tile is in conventional thickset mortar. The floor will last longer, will be less likely to crack, and has the lowest toxicity. Thinset mortar is a combination of cement and epoxy. It is the next best option as the epoxy sets up quickly and off-gasses for only a short time. If you plan to use adhesive and grout, look for water-based, nontoxic products.
Glass tile made from old bottles, auto glass, and recycled fluorescent light tubes or ceramics can be found with a quick search of the marketplace. These tiles are highly acclaimed for their rich color and durability.
Recycled Rubber Floors
Rubber flooring is attractive for its resilience. Most often found in gyms and health clubs, it’s also a good flooring option for commercial kitchens—places that usually have good ventilation. Rubber off-gasses during most of its life. Recycled content reduces some of this effect but the smell is constant. It is a much better product for outdoor play areas than for children’s playrooms inside.
Reclaimed flooring is available locally and through various sources nationally. While old-growth wood is not a green flooring choice, reclaimed old-growth timber flooring can be your way around this problem. Vast quantities of old-growth lumber can be found in old warehouses, buildings, bridges, and other structures. Reclaimed wood provides the benefits of old-growth timber without the environmental costs. Another source for wood products is local lumberyards that reclaim urban forests when trees die or are cut down to build new homes and businesses.
Pay attention to where the materials in your home come from, how they are made, and what they might emit into indoor air. Reclaimed materials are readily available and create unique creative spaces. The marketplace is filled with nontoxic alternatives to the everyday paints, sealants, and adhesives we’re used to buying. Creating a well-designed space that will last throughout a home’s various inhabitants is as important as selecting materials with recycled content and low embodied energy.
Best Eco-Friendly Flooring Practices
- Establish an effective interior air barrier.
- If available, choose drywall whose core is made with residue that’s taken from air scrubbers at coal-fired power plants.
- Choose low-VOC or no-VOC paints, caulks, and adhesives as well as water-based finishes rather than solvent-based products.
- Avoid wood products that use urea-formaldehyde as a binder.
- Use wood products made with renewable or recycled content.
- Consider the distance that building products must be shipped and choose those produced locally or regionally over those that come from overseas.
- Specify wood that’s certified by the Forest Stewardship Council.
- If carpet is used as a floor covering, favor natural materials such as wool or sisal but avoid products that contain styrene butadiene latex binders and wool that must be fumigated when it enters the country.
Reprinted with permission from Green From the Ground Up, published by Taunton Press, 2008.