USGBC Issues Report on PVC Use
WASHINGTON — A technical advisory committee for the U.S. Green Building Council released a report that does not recommend imposing restrictions on the use of PVC in buildings seeking LEED certification until there is more research on the subject.
The Technical and Scientific Advisory Committee recently published the report that states PVC — also known as vinyl — did not perform better or worse overall than alternative materials with regard to its impact on the environment or human health in commercial building applications.
“There has been concern in the environmental community that PVC had some potential environmental and human health impacts that were problematic,” says Malcolm Lewis, chairman of TSAC. “The bottom line is that there’s no simple yes or no answer.”
The committee began studying PVC in 2002 after concerns arose regarding the effects of PVC on the environment and human health. USGBC members serving on the LEED for Commercial Interiors Development Committee proposed giving builders a credit for not using the material.
TSAC conducted life cycle assessments and risk analyses to determine whether, for the building applications studied, vinyl was consistently among the worst materials in terms of environmental and health impacts. More than 2,000 documents providing information about PVC from stakeholders and independent sources were also considered.
“The challenge is, if you decide not to use PVC, you have to decide what you’re going to use instead for those applications where you would have used the PVC-based material,” Lewis says. “Whether you think environmental impacts or human health impacts are more important affects the conclusion you reach.
“We did a very exhaustive amount of life-cycle assessment, which looked at the different phases — mining, manufacturing, use of the building, etc. — that have an effect on whether PVC is better or worse than the alternatives.”
The committee selected four building applications for analysis, including siding; drain, waste and vent piping, resilient flooring; and window frames, all of which frequently use vinyl. For the siding study, PVC was compared with aluminum, wood and fiber-cement. For piping, PVC, ABS (acrylonitrile butadiene styrene), and cast iron were considered. The flooring study examined sheet vinyl, vinyl composition tile, linoleum and cork, and for window frames, PVC was compared to aluminum and wood.
“We looked at alternatives that were used in the marketplace and were reasonable alternatives to the PVC for that application,” Lewis says. “It wasn’t intended to be an exhaustive list of every application. It was so we could say, ‘Compared to some available alternatives, here’s how PVC stacks up.’”
With regard to environmental impact, PVC performed better than alternative materials in three out of the four building applications — window frames, cast iron pipe and siding, the report states. Aluminum was considered the worst material for window frames; cast iron pipe was the worst material for piping; and aluminum was considered the worst material for siding. The resilient flooring study showed that sheet vinyl performed the worst among all the materials.
The human health impact of vinyl and the other materials was studied in three different life cycle phases: cradle-through-use, meaning from the material’s inception to the end of its useful period; end-of-life, which factors in accidental landfill fires and backyard burnings; and occupational exposure.
In the cradle-through-use assessment, PVC performed better than most alternatives studied for window frame, siding and piping applications, while it performed worse than most materials in the resilient flooring study, because it presented significant cancer-related risks.
The end-of-life study shows that, when burned, vinyl was consistently ranked among the worst materials studied for human health impacts. If ignited, PVC can release toxins during building fires that have the potential to incapacitate occupants and firefighters.
Vinyl was among the worst performing materials in the occupational exposure assessment, although the panel did experience some data gaps in this study.
“One of the things that became clear is that, while there was a lot of data — we did a huge amount of review of publications and peer articles — there are still a lot of gaps,” Lewis says. “We’re hoping that we can work with the industry and the environmental community to try to develop data to understand a lot of these environmental impacts better.”
The LEED steering committee plans to review the report and its recommendations before making any policy changes or revising the USGBC’s rating system. The use of life cycle assessment, a process that Lewis says was pioneered in this report, will most likely be used prominently in the development of future versions of LEED.