Denver’s building electrification rules survived their federal preemption challenge on August 7, and the ruling makes the national picture more contradictory, not less.
Judge Philip A. Brimmer of the U.S. District Court for the District of Colorado granted the city’s motion to dismiss. The clerk entered judgment on August 13. The case, brought by the Restaurant Law Center together with the Colorado Restaurant Association and other business groups, was filed July 3, 2024.
The EPCA preemption argument, and why it lost
Plaintiffs argued that Denver’s gas appliance restrictions in its building code, along with the Energize Denver Building Energy Benchmarking and Performance regulations, are expressly preempted by the Energy Policy and Conservation Act. EPCA preempts state and local regulation of a covered appliance’s energy use and efficiency.
The court found the plaintiffs’ members had shown a risk of future harm imminent and substantial enough to establish standing, then ruled against them on the merits. On preemption it aligned with Second Circuit reasoning: a regulation that effectively bars use of a covered appliance has little to do with that appliance’s “energy use” as EPCA defines the term, because the statutory definition is a standardized measure set by federal test procedures before the product ever reaches a consumer.
Put plainly, the court drew a line between regulating how efficient a stove must be, which is federal, and regulating whether a building may be piped for one, which it held is local.
Three circuits, two answers
The Ninth Circuit struck down Berkeley’s gas ban in 2024 on the opposite reading. The Second Circuit upheld New York State and New York City limits on fossil fuel appliances in new construction in June 2026. Now a Colorado federal court has come down with the Second.
For designers and contractors working across circuits, that is not an academic problem. A national restaurant or multifamily developer standardizing on a gas-fired kitchen or heating package has genuinely different legal baselines in San Francisco, Denver and New York, and the split raises the odds this reaches the Supreme Court. Until then, the practical answer for anyone standardizing prototypes is to design the electric version and treat gas as the variant.
What it means for Denver work in the ground
The immediate effect is that Denver can proceed with its next Energize Denver compliance waves. Those rules drive equipment selection, electrical service sizing and retrofit budgets on every large commercial and multifamily building in the city, and owners who have been slow-walking capital plans pending the litigation no longer have that reason.
Two caveats on the reporting. Local outlets describe the dismissal as with prejudice; the docket shows an order and a clerk’s judgment, and the opinion text isn’t public as of this writing. Separately, a different Colorado case concerning the state’s Building Performance Standards was dismissed without prejudice, and the two shouldn’t be merged.
The retrofit economics are the same math playing out in every large city with a performance standard. Chicago’s $162 million conversion of 500 North Michigan Avenue is putting 320 apartments into a 1968 office tower, and the mechanical and electrical scope on that job would look materially different if it were being designed for gas today. Increasingly, it isn’t.