The historic Shaheen-Portman energy bill making its way through the U.S. Senate enjoys rare and broad bipartisan backing, with the likes of Earthjustice and the Vinyl Siding Institute both announcing full-throated support. But the American Institute of Architects (AIA) and more than 350 other organizations have warned that they will fight Shaheen-Portman (a.k.a. the Energy Savings and Industrial Competitiveness Act of 2013) if a certain amendment is adopted.

Thanks in part to a handful of energy-efficiency advocates, that amendment may very well pass. The proposed amendment guts a hard-won provision of the 2007 Energy Independence and Security Act (EISA)—a few paragraphs in Section 433 targeting the eventual phase-out of fossil-fuel-generated energy in federal new construction and major renovations by 2030. Dubbed “The All-of-the-Above Federal Building Energy Conservation Act of 2013” by its cosponsors John Hoeven (R–North Dakota) and Joe Manchin (D-West Virginia), the proposed amendment is currently under committee review as a standalone bill and has strong support from the American Gas Association (AGA).

EISA “is all about advancing efficiency in federal buildings, and we are all for that,” explains Paula Gant, vice president of regulatory affairs at AGA. “We feel strongly that natural gas is a part of that.” The Hoeven-Manchin bill proposes three major changes to EISA. First, it redefines “major renovation,” shifting away from a cost-based definition to one based on energy performance. Second, the proposal focuses on efficiency instead of fuels, requiring new construction and major renovations to be designed for a 30 percent reduction in energy use compared with current ASHRAE 90.1 or International Energy Conservation Code (IECC) standards. Third, it extends the timeline for reducing actual energy consumption in federal buildings, requiring a 45 percent decrease in energy use intensity (EUI) by 2020.