After nearly four years of collaboration, the long-awaited Window Product Category Rule (PCR) has finally been released.

The PCR, which can be viewed here, was established “to provide a detailed method for developing a business-to-business (B-to-B) Environmental Product Declaration (EPD) to support comparable, informed, and objective sustainable purchasing of windows,” according to the document. The scope of the PCR is “Cradle to Gate with options.”

According to the Institute for Environmental Research and Education (IERE), PCRs are based on Life Cycle Assessment (LCA) and “spell out, for example, choices in scope, calculation steps, and areas of environmental impact that are specific to the product being considered and its supply chain. PCRs are a crucial step in the EPD process to insure that harmonized and consistent calculations and procedures will be used each time an EPD is created for a product.”

Funded by the National Renewable Energy Laboratory, the Window PCR conforms with ISO 14040, 14044, 14025, 21930 and the IERE Earthsure Program. EPDs developed using it will be valid for the U.S. Green Building Council’s LEED v4 Program.

The rule, published last Thursday, covers “exterior vertical window products provided by a single source supplier using industry wide components or windows based on North American data where available for use in buildings, including skylights, single opening windows, curtainwalls, and storefronts.”

During the development process, the committee reviewed two other PCRs for window products—the EPD-Norge PCR for Windows and Doors (April 2009) and the German IBU PCR for Windows and Doors (July 2012)—but several aspects of the existing PCRs “caused the PCR Committee to reject following these exclusively.” The window industry, for example, wanted a PCR that was only for windows, not including doors, and the data sources and compliance requirements in the two PCRs were European and not relevant in North America.

The document notes that there is an existing PCR for window glass titled “GANA PCR for Flat Glass: UN CPC 3711” but that it refers to only a portion of a window.

The PCR was developed by the following industry members: Jason Chesley, Pella Corporation; Kara Goscinski Cach, Guardian Industries; Jeff Haberer, Trulite Glass and Aluminum Solutions, formerly Cardinal Glass Industries; Kerry Haglund, Efficient Windows Collaborative; Jeffrey Inks, WDMA; Jim Krahn, Marvin Windows and Doors; Greg McKenna, Kawneer Co. Inc.; Annie Perkins, Andersen Windows; Helen Sanders, SAGE Electrochromics; Rita Schenck, IERE; Mark Silverberg, Technoform NA Inc.; Urmilla Jokhu-Sowell, GANA; Richard Walker, AAMA; and Margaret Webb, IGMA.

VIEW THE CRADLE TO GATE WINDOW PRODUCT CATEGORY RULE HERE