A QUICK SURVEY OF THE BUILDING materials landscape shows that more manufacturers today offer products made with recycled content. This should be good news. But some design professionals have charged that recycled-content products harm indoor air quality more than traditional ones do. The California Integrated Waste Management Board—an agency responsible for managing the state's solid waste stream—launched a study to determine whether that charge holds water.

In its “Building Material Emissions Study,” the waste board concluded that recycled-content building products and traditional ones, on average, performed about the same in terms of indoor air pollution. In other words, recycled-content products do not degrade indoor air any more than traditional ones. However, in some cases, products labeled green or expressly claiming to be low-VOC did not perform well.

On the heels of this report, the state's Collaborative for High Performance Schools —a board made up of government, private, and nonprofit members whose purpose is to increase the energy efficiency of schools in California—is set to release a list of manufacturers and their products that have been certified as meeting the organization's Low-Emitting Materials criteria.

Sustainable Buildings One of the most environmentally forward states, California believes in using recycled-content building products in schools and state construction projects to promote sustainable building practices and meet a state mandate to divert 50 percent of its waste from landfills. Members of the design community, however, charged that emissions from recycled building products contributed to poor indoor air quality. “We were getting push-back from people who said the products off-gas so they could not use them,” says Tom Estes, manager of the state's sustainable building program.

Prior studies had reported on emissions from various building materials, but none had compared standard and alternative building products. Because of this lack of data, many recycled-content materials have been subject to greater suspicion than their traditional counterparts.

The waste board's emissions study examined 77 products—43 considered alternative and 34 labeled standard—including such residential-applicable items as carpeting, fiber-board, gypsum board, plastic laminates, resilient flooring (rubber and nonrubber based), and thermal insulation. The report set out to estimate volatile organic compound (VOC) concentrations in a new or renovated standard-sized classroom measuring 40 feet by 24 feet by 8 1/2 feet with a ventilation rate of 0.9 air changes per hour, and in a standard-sized state office that is 10 feet by 12 feet by 8 1/2 feet with a ventilation rate of 0.75 air changes per hour.

Though the study used an office and a classroom, the results can be applied to residential spaces as well, says Estes. It is important to note that products exceeding the concentrations might be even more alarming in residential use since a room in a house can be an even smaller space.

Report Card In general, the report says traditional and alternative products exceeded the concentration limits equally. It also says that alternative products performed the same in the classroom and the office, but twice as many standard products exceeded the limits in the office space than did so in the classroom.

The study raises questions about traditional as well as alternative products. For example, two standard gypsum products exceeded VOC concentration limits for the office calculations, but the alternative products that contained recycled content in the gypsum core did not exceed any of the limits. The alternative zero-VOC paints tested with a zero-VOC primer were much lower emitting than all other paints, but additional indoor air quality results showed that several alternative brands exceeded classroom and office calculations. One of the two alternative insulation products, sold as formaldehyde-free, also exceeded the concentration limit for the office calculations. And, of the five alternative carpet products tested, two exceeded the concentration limits for both office and classroom.

One important aspect of the study is the conclusion that the results conflict with those reported by industry-supported product certifications such as the Carpet and Rug Institute's “green label” testing program and paint manufacturers' low- or no-VOC labels.

The National Paint & Coatings Association in Washington was unfamiliar with the study and could not comment. The Carpet and Rug Institute, in Dalton, Ga., however, had serious concerns with the report. “We are distressed about the report, and the way it was conducted,” says Frank K. Hurd, vice president and COO. “It is the biggest piece of garbage on the Web.”

The waste board does say that due to a limited number of samples, the results of the study should not be used to make generalizations about recycled-content products vs. traditional ones. Still, the report provides some evidence in the ongoing debate. “There is no longer a valid argument for not using alternative building materials,” Estes notes. “No longer can the building community say that recycled-content products degrade the indoor air” more than traditional ones.