When you consider the practical properties of polyvinyl chloride (PVC) - durability, versatility and low price - it is easy to understand how it has become such a common construction material, with applications as roofing membranes, siding, pipes and plumbing, conduit, window frames, window blinds, molding and trim, and fencing. But perhaps it’s time to be more cautious about its use. According to a new whitepaper report by Perkins+Will, "What’s New (and What’s Not) With PVC," in spite of recent advances in plastic chemistry PVC is still responsible for a range of environmental and human health hazards created in multiple stages of its manufacturing process.
Unlike most other plastics, PVC contains chlorine. Part of the halogen elements on the periodic table, compounds of chlorine have been the source of many of society’s most difficult chemical contamination issues since World War II: for example, the herbicide “Agent Orange,” DDT, dioxins, PCBs, and CFCs. This intrinsic chlorinated chemistry means that even recent innovations to replace toxic additives with natural alternatives, marketed as “clean-vinyl” or “bio-vinyl,” will not eliminate the emission of cancer-causing carcinogens and dioxins created in its production. In addition, PVC’s recycling process releases additives, and becomes a pathway for the reintroduction of legacy contaminants the green vinyl alternatives have been designed to avoid. As a result, the report, as well as leading materials rating systems such as the Living Building Challenge and Cradle to Cradle product certifications, suggests that the only way to avoid these health hazards is to eliminate PVC use altogether.
To encourage designers to look to other material solutions, Perkins+Will have compiled the following list of common applications of PVC, and the alternative materials they can be replaced with:
Pipes & Plumbing
Alternative Material: Cast Iron, Concrete, Copper (interior only), HDPE, PEX, Polypropylene
Description: “Depending on the plumbing application, a variety of materials can be used to construct pipes for hot and cold potable water, as well as waste pipe and sanitary drains”
Resilient Flooring
Alternative Material: Cork, Linoleum, Rubber
Description: “Cork and linoleum both source their primary ingredients from plants and natural minerals. Be sure to select a cork floor made without a PVC backing. While rubber flooring is based on styrene-butadiene chemistry and has a number of concerns, a 2009 evaluation of resilient flooring still indicated it as a preferred option over PVC.”
Carpet Backing
Alternative Material: Polyvinyl Butyral (PVB)
Description: “Unlike similarly sounding polyvinyl chloride, polyvinyl butyral is not a chlorinated plastic and therefore avoids many of the lifecycle hazards associated with chlorine. PVB is a polymer primarily used in automotive safety glass, and can be recycled into carpet backings.”
Wall Covering
Alternative Material: Textiles, Polyethylene
Description: “Fabrics offer an alternative to PVC wallcoverings. Xorel, made by Carnegie Fabrics, features a polyethylene fabric made from sugar cane rather than petroleum.”
Wall Protection
Alternative Material: Aluminum, Bio-based Polymers, Stainless Steel, Zinc
Description: “Metal sheeting and plates offer a simple alternative to wall protection, while some corn-derived polymers are also entering the market.”
Window Blinds and Shades
Alternative Material: Textiles, Polyethylene, Aluminum
Description: “When specifying fabric shades, avoid stain resistant, anti-static, or other surface treatments that may introduce unwanted hazards.”
Window Frames
Alternative Material: Aluminum, Wood
Description: “Wooden and aluminum window frames are readily available in a variety of colors.”
Every material comes with some level of footprint, and it is important to recognize that using alternative materials may require tradeoffs with other environmental attributes, such as deforestation impacts from wood flooring. But environmentalists seem to agree that avoiding PVC in building material choices is nearly always preferable from an overall human health and environmental perspective. As per Perkins+Will's suggestion, eliminating it could be the next step toward a healthier and lower-impact future.