New stand-alone guidelines for reducing operational greenhouse gas (GHG) emissions will accompany the scheduled 2028 update of the ASHRAE 90.1 energy standard for buildings other than low-rise residential buildings. The planned optional companion document to the widely referenced energy efficiency standard gives new prominence to guidelines that appear as informative appendices in the 2025 iteration.

“By creating a dedicated pathway for operational emissions reduction, ASHRAE can respond to emerging market needs without losing sight of the proven energy efficiency principles at the heart of Standard 90.1. It’s about giving our industry the right playbook for the challenge at hand,” says Sarah Maston, ASHRAE president for 2026-27.

The new stand-alone document responds to increasing demand from both building owners/managers pursuing decarbonization and net-zero operations, and regulators looking to reference a standard in their codes and bylaws. The template of building requirements and procedures for reducing operational emissions in commercial buildings will be developed through the same consultative process and technical working group input that drives updates to the 90.1 standard.

ASHRAE administrators promise enhanced “usability, flexibility and responsiveness to market demands” to make it compatible with digital tools and allow for a range of approaches to compliance, including accounting for the availability of renewable energy. Meanwhile, they reaffirm the 90.1 standard’s focus on energy efficiency with requirements justified by energy costs.

“Standard 90.1 has helped define energy-efficient commercial building design for more than 50 years, and this direction strengthens the foundation that has made it one of the world’s most influential building energy standards,” Maston says.