Question

What type of carpet or manufacturer of carpet produces the least VOCs?

Asked by Colleen Baxter
Stevensville, MD

We would like to put wall-to-wall carpet in our newly refinished basement and must consider the fact that I am extremely sensitive to even low levels of VOC's. What type of carpet or carpet manufacturers would you suggest?

Answer

Cynthia Phakos

Answered by Cynthia Phakos

Los Angeles, CA

Koffka Phakos Design

August 8, 2011

Before we discuss what carpet you should use we should first touch on the Carpet and Rug Institute's (CRI) program for selecting and installing carpet.

  • Their Green Label Plus (GLP) Indoor Air Quality (IAQ) program first launched in 1992, has become the standard for emissions of VOC’s in carpet, cushions and adhesives.
  • The maximum allowed VOC emission from new carpet in this test program over a 24 hour and 14 day period, is 0.5 milligrams per meter square, which if very low.
  • Tests done for carpet emissions demonstrate that with proper ventilation, emissions will dissipate within in 48 to 72 hours (www.nps.gov/sustain/spop/carpet.htm).
  • On the CRI website you will find a list of Carpets, Adhesives and Cleaners that meet their Green Label Plus standards.
  • The Carpet and Rug Institute also provides installation guidelines for your carpet as well.

Installation

Moisture in basements.  Installing the carpet on a basement concrete subfloor can be a risky proposition given moisture related problems in a place not built for habitation.

  • A waterproofing or foundation specialist can assess your situation prior to installing carpet, if this hasn’t been done yet.
  • Moisture under carpet can cause mold and mildew which can contribute or cause health problems.
  • Basement water problems are solvable, and you definitely want to do this right. As I grew up in the northeast, where we all had basements I know first hand the problems that can arise, installing a carpet in basement.

Carpet installation.  Installing broadloom (wall to wall) carpet on a concrete subfloor typically requires a glue-down installation. I have seen carpet installed with the tack-less strip method on a plywood subfloor on sleepers but this requires additional height and is more costly.

  • Adhesives are one of the biggest causes of VOC emissions and as the basement probably doesn’t have great ventilation, you will want to select a 0 VOC adhesive.
  • Performance Broadloom Adhesive 2100 manufactured by XL Brands, is one that we use and the Material Safety Data Sheet lists the VOC content as “zero” grams per liter.
  • Before installation, the concrete substrate must be tested for moisture and alkalinity. A good carpet installer can do this for you.

Ventilation. The Carpet and Rug Institute requires the supplier to unroll and air-out carpets in the warehouse before bringing them to your home, to minimize on the off-gassing.

  • As you are installing the carpet in the basement where there may not be adequate ventilation you should check and see if the installers could air it out for the 48 – 72 hours in the warehouse, or if you have the space you could do the same.
  • Also, carpet can act as a sink for VOC’s emitted from other materials, so you should select low VOC paints, sealers and furnishings. Carpet traps dust, pet dander and other particulates that might contribute to your sensitivity. Carpet companies and the CRI promote carpet as reducing airborne particulates as they are essentially trapped in the rug.
  • However you want to look at it, you will want to select a carpet that is easily cleaned. And again you will need to select a non-VOC cleaner. Wool carpets soil the least but may not be appropriate for a basement space.

Carpet Selection

Carpet is made up of 3 components:

  • the face fiber,
  • the carpet backing, and
  • the adhesive.

Face fibers.  A natural wool, cotton or grass (sisal) will give you the most chemical free carpet, especially if it is not dyed.

  • Earthweave, Nature’s Choice and Hibernia are all good choices.
  • Carpet made from synthetic face fibers are mostly nylon 6, nylon 6.6, polyester, and polypropylene (PP).
  • There are some newer materials such as Mohawk’s Smartstrand which is partially produced from corn sugars that would be worth considering if you are going for a synthetic fiber.
  • Check this Q&A by David Rodriguez and this one by William Janhonen for other carpet types.

Adhesive and backing.  This is where VOC’s are most frequently found. Most backings are a polypropylene fabric and latex, or poly-vinyl.

A cushion-backed carpet works best on concrete as it adds some cushioning to the floor (more often this would be a commercial carpet). The CRI has published a Standard for Installation of Residential Carpet which you can read here.

Recommendation

Given the moisture, ventilation and VOC issues, if you are going to install carpet, a carpet tile makes the most sense

A great carpet tile manufacturer is FLOR, a division of Interface, a pioneer in the sustainable carpet world and have the lowest VOC’s in the industry.

  • The backing is made of a vinyl compound rubber which is pre-coated with Intercept, an anti microbial finish which prevents mold or mildew.
  • The face fiber is woven (or punched) into the backing so there are no adhesives.

When installing the carpet tiles, you should start with a water based concrete sealer. You could then use Moisture Guard 2.0, which is a sheet good used to further protect against moisture and is part of their commercial line. FLOR’s carpet tiles can be installed with their TacTiles connectors, which are glue-free adhesive squares that adhere the tile to one another and create a floating floor, which means that no glues are required.

Carpet tiles can be used in playful color patterns, or be a monochromatic whichever suits your style. The look would be appropriate for a refinished basement. Also, should there be any moisture problems you can easily remove a tile.

The carpet tiles can be installed after off-gassing more easily than broadloom due to their size. I believe that when you open the box you will find that there are no odors.

Should you desire an alternate flooring choice, after this discussion, I would recommend Wicander’s Cork floating floor system which requires no adhesives. The cork panels come in 1’x3’ panels and can be prefinished. Their heavy wear finish is warrantied for 25 years and all of their products are Green Guard Certified for Indoor Air Quality.

 

For more information:

Check the green flooring topic of GreenHomeGuide's Know How section for tips and further explanation about carpet.

Tagged In: basement flooring, green carpet

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