Sustainable Building Technical Manual - Etn-presco.net

– One method of low-emission carpet construction is to eliminate the latex bondthrough “fusion bonding.” Carpet made in this manner has a sponge plastic backinginto which the face fiber has been heat-welded. It has a low indoor pollutionpotential. Needlepunched carpets are also made without latex. Among latex-bondedcarpets, including wool products, emissions vary widely. Some carpet manufacturershave made considerable effort to provide low-emission products and provide testresults, including VOC and other emissions at different time periods. 13– Airing out new carpet has often been recommended as a pollution-reductionmeasure, but the evidence of its effectiveness is still being studied. While this canhelp reduce some short-term volatile emissions and reduce odors adsorbed duringmanufacturing and storage, other carpet contents can produce emissions formany months.Finished Concrete FlooringFinished concrete flooring is an integral system of slab and finish produced by addingcolorants and sealers to the topping concrete either before or after it cures. The concreteis usually stamped with tile patterns and grid lines to control cracking and to enhance itsappearance. It is a durable and low-maintenance finish.❑ Resource-efficient options– Finished concrete may be appropriate for areas that would otherwise be surfacedwith tile or terrazzo. Systems with integral color added to the entire topping layerare more resistant to damage and less likely to require recoloring than systems dyedafter the concrete is laid. Proper sealing and waxing can lead to longer life.❑ Health and pollution issues– Finished concrete is low in emissions.– The choice of sealers is the main concern. Water-dispersed acrylic sealers and waxesmeeting low-volatility standards are among the safest.PaintsPaint is an important indoor air pollution and toxic waste consideration. Volatile emissionsfrom paint tend to be short term—that is, they decrease to a small fraction of thewet emission rate within a few days or weeks. Some of the most toxic emissions frompaints and coatings are from evaporating solvents and a wide variety of volatiles releasedby oxidation. These volatiles are produced by both solvent- and water-based paints. Asmuch as 12 percent of water-based paints may be solvents, although currently paints forinterior applications are available containing very little toxic solvents. Water-borneacrylics are clearly preferable to alkyds (solvent-based oil paints) for handling safety, andthey are highly durable and produce no hazardous waste from cleanup.❑ Resource-efficient options– Several U.S. companies are now providing recycled paints made by mixing leftovermanufacturing product with returned customer products. These recycled paints aregenerally good-quality acrylic latex paints, suitable for moderate-duty interior use,although the color range is quite limited.– For exterior use, solvent-based products are required in some applications. Thesepaints can be recycled either through municipal programs or through paint suppliers.❑ Health and pollution issues– The first priority is to avoid paints containing lead, mercury, hexavalent chromium,and cadmium. Although regulations have nearly eliminated many of these toxiccomponents from consumer paint lines, industrial and commercial paints may stillcontain them. Check MSDSs for these toxic contents as they must be disclosed.– Selecting paints with the least volatile emissions, provided they still meet the otherproject criteria, is important. Many such paints are water-dispersed acrylic and latexproducts. Some of the emerging third-party certification groups provide environmentalstandards for paints.