Flooring

Carpet: I am often asked “to carpet or not to carpet?” While my preference from an IAQ perspective is to avoid or reduce carpet as an interior finish, I know there are market pressures and preferences that will trump my position. My aversion is based on the fact that these products can contain potential toxic chemicals from synthetic fibers; carpet backing and padding; fire, stain, and moth proofing; heavy metal dyes; and floor adhesives and substrates. And where there is the potential for spills or trapped moisture—kitchens, bathrooms, and below-grade basement spaces—carpet should not be installed.

If you are going to specify carpet products, select your options from a reliable source with certification. We start with CRI Green Label Plus for residential products. We also step outside the box using commercial products (carpet tile or broadloom) for residential applications, with applicable ecolabels, including Cradle to Cradle (C2C), EcoLogo, SCS Sustainable Choice, and SMaRT.

Natural carpeting without synthetic dyes is high on my list of recommendations—use natural, organic fibers like wool, silk, cotton, or linen with rubber backing—for a highly durable, long-lasting alternative. If you go the natural route, ask about biocide treatment (moth repellent) for wool and cotton carpets.

Recycled-content carpet, especially in the form of carpet tile, is a resource-effective solution. Using very few non-renewable resources, manufacturers are including up to 100% recycled face and backing and a solution-dyed, recycled-content nylon fiber.

Where new carpet odor is a concern, require suppliers to unroll and air out carpets in a clean, dry warehouse before bringing them into the building. We let it air out in a well-ventilated area for a couple of days before installation—either the supplier or installer are able to support this strategy if you plan ahead. During and after installation, open windows and turn on fans/ventilation systems to clear the air. Tack down carpets rather than using adhesives, and let owners know that they need to vacuum often, at least once a week.

Hard-surface flooring: I have a strong preference for hard-surface flooring (e.g., cork, linoleum, concrete, wood, and tile) as it is healthier and typically made of solid inert products that are durable and less toxic.

I would specify cork and linoleum over carpet and vinyl products for good IAQ and source reduction. Resilient flooring is a natural choice that comes from rapidly renewable resources, contains recycled content, is biodegradable, and does not emit VOC gases. Plus, it offers inherent acoustic qualities, cushioning under foot, and built-in antimicrobial properties. Carefully review the product information for low-emitting, formaldehyde-free, and water-based binders, adhesives, finishes, and natural pigment-based stains. For IAQ priorities, turn to Greenguard, and for multi-attribute certifications, EcoLogo, FloorScore, SCS Recycled Content, and SMaRT. We avoid vinyl-based products (tile/sheet goods) as they are made from PVC, which emits VOC gases and is not biodegradable.

For a resource-effective solution offering thermal mass, reuse of existing building materials (in remodels) and low-VOC finishing methods, use slab-on-grade concrete. We finish with linseed oil and nontoxic stains, or a ground finish with a polished surface that meet SCAQMD Rule 1113. Low-emitting sealants and colorants are readily available that are bio-based, water-based, and/or meet third-party certifications. If a client is not sensitive to fly ash, ask for it to be added to the concrete mix to reduce the amount of energy-intensive Portland cement.

Wood flooring is the ultimate for long-lasting qualities, in some cases outliving the building. It can be refinished countless times as long as it is not a thin veneer and is easy to clean. I’ve not met a client yet who doesn’t love the look, feel, and performance of wood floors. It’s important to scrutinize the binders and fillers added to the finished product and use Greenguard for low-emitting product options. Look for products carrying the Forest Stewardship Council (FSC), Sustainable Forestry Initiative (SFI), or SCS LegalHarvest certifications. Engineered and pre-finished wood products are another alternative. With engineered wood, take care that the manufacturing process has no added urea-formaldehyde and pay attention to the possibility of synthetic components. The best option again is using products with FSC or SFI certifications.

And I have to mention bamboo although it has come under question as a sustainable choice due to the fact that most of it comes from Asia. Bamboo is a viable option because it is rapidly renewable, has tensile strength that exceeds oak, typically has no added urea-formaldehyde, and comes with forest certifications and low-emitting factory finishes.

For all flooring types, use adhesives, finishes, sealers, and substrates that are nontoxic, low emitting, and third-party certified. When specifying these products, look to SCS Indoor Advantage, FSC, and SFI for meeting the material goals.

Walls

Thinking back to my earlier comments on wall assemblies, and to further prevent the possibility of mold and mildew, we try to avoid the use of impermeable, surface-applied wall coverings as they can trap moisture in the wall surface or within the wall cavity. Wall coverings are manufactured with paper, fiber, or PVC. PVC-based (vinyl) wall coverings emit VOC gases into the indoor air and, when manufactured, create a toxic by-product. We specify uncoated, permeable wall coverings made with eco-friendly technologies like biodegradable paper with recycled content. When taking into account a product’s composition, review the dye compounds, backings, and finishes, too. For durability and cleanability, look for PVC-free alternatives that do not contain phthalate plasticizers. Phthalates are endocrine disruptors (compounds that mimic natural hormones) considered a health hazard by many medical professionals. Equally, traditional wallpaper paste is preferred to self-stick wall coverings because the self-stick adhesive has a higher VOC content. Look to third-party certification from the recently released NSF/ANSI Standard 342.

Our first preference for wall treatments is an integral color, earthen-based plaster for its inherent beauty, breathability, low-emitting qualities, usual nontoxicity, and high level of performance. These products have low embodied energy and are typically made from clay earth, mineral pigments, and borax combined with natural or synthetic additives. Ensure that the sealants and/or topical finishes support proper moisture management strategies, although some products that we have used actually help to moderate indoor humidity in dryer climates. Focus on products with SCS Indoor Advantage Gold and ISO 14001 certifications.

Specify paint products that are low emitting, high performing for the given application, and meet GS-11 standards. Some paints still add VOCs to improve durability, enhance the finish, and decrease drying time, and manufacturers have listed VOC levels without including their colorants—so doublecheck your VOC/SVOC levels. Many of the new generation of paints, coatings, and finishes are now water-based, acrylic products that are strong and durable to meet health, sustainability, and performance goals. Look for certifications from Green Seal, C2C, EcoLogo, and Master Painters Institute.

Tile

By nature, tile is inert so an IAQ certification isn’t necessary. Its inherent sustainability delivers on health qualities, ease of maintenance, and enduring performance. Many lines offer a high recycled content and are made in the United States. In addition to Greenguard Children & Schools certification, look for Green Squared, a new initiative by the Tile Council of North America certifying sustainable products. It is a multi-attribute standard for tile and eventually tile installation materials conforming to ANSI A138.1, validating manufacture product claims and providing us with equal product comparisons to an established baseline.

Cabinets

Cabinetry has a bit more complexity due to its components and assembly. Your choices will contribute positively to IAQ and resource goals by looking for waterborne finishes, low chemical emissions, recycled content, and product certification. Greenguard for Children & Schools, FSC, and SFI certification are again our first choices for the wood components. For hardware and hinges, request SCS Recycled Content certification. Lastly, consider second-party certifications from the Kitchen Cabinet Manufacturers Association, which developed its Environmental Stewardship Program to encourage practices that benefit the environment and society.

Countertops

The most effective countertops are durable, high performing, easy to clean, resource effective, and healthy. Countertops are available in 100% recycled content including paper, glass, stone, and aluminum-based products, a great source reduction in materials. Greenguard Children & Schools and SCS Indoor Advantage Gold will help guide you toward your IAQ goals followed by SCS Recycled Content for resource efficiency and NSF/ANSI 51 for compliance with healthy food zone use.

Wrapping It All Together

Interior designers searching for sustainable and healthy products would make great detectives, because our research explores the forensic nature of product options, including their chemical compounds, molecular structures, and the implications of their installation methods. Finding the materials that meet a project’s goals and objectives demands a thorough research process. I’ve been doing this for more than 30 years, and every week there is a new product, every month a new certification, and it takes commitment to practice due diligence and investigate the details and assure compliance with the high standards that we practice for a healthy home. And, as you put your next project team together, look for a qualified, credentialed, professional designer who can help you achieve your goals to design and build a safe and healthy high-performance home.

Annette K. Stelmack, USGBC Faculty, LEED AP BD+C, ASID Allied, is the owner/principal of Boulder, Colo.-based Inspirit, a sustainable interior design firm.