New Law Will Make Housing More Affordable
DENVER, CO - Governor Jared Polis yesterday signed legislation into law that will save people money on housing by updating building codes to only require one stairwell for certain multi-family buildings.
“This smart stair policy is safe and will help us create more housing Coloradans can afford,” said Speaker Pro Tempore Andy Boesenecker, D-Fort Collins. “Firefighting technology and fire protection techniques have significantly improved in the last few decades, and it’s time that we modernize our building codes to account for these safety improvements and reduce the cost of building multi-family housing. This law reduces the cost of building family-sized apartments and condos that will help us meet Colorado’s housing needs and save people money on housing.”
“Single-stair buildings are a safe and practical solution that make it far easier to build apartments with enough bedrooms to comfortably house Colorado families,” said Senator Matt Ball, D-Denver. “Single-stair buildings can also be impressive architectural additions to our neighborhoods. This new law modernizes our building codes and positions Colorado at the forefront of innovative solutions to our housing crisis."
“Colorado Democrats are committed to passing legislation that will make housing more affordable,” said Rep. Steven Woodrow, D-Denver. “This law eliminates second stairwell requirements for certain buildings to drive down building costs and create more livable space. Coloradans sent us here to pass policy that will make our communities more affordable, and this policy will help open up more housing opportunities that work for every budget.”
“Colorado is facing a housing crisis and we must explore every option to build more homes that families can afford,” said Senator Nick Hinrichsen, D-Pueblo. “Modernizing outdated building codes to allow for single-stair apartment buildings, where modern technology and building materials makes doing so safe, is a simple and effective solution that will open up opportunities to build more affordable housing and revitalize our neighborhoods. This policy is a critical way that we can increase housing supply, drive down costs, and ensure that every Coloradan has a safe, affordable place to call home.”
Beginning December 1, 2027, HB25-1273 requires a municipality of 100,000 or more residents that is served by an accredited fire protection district, fire department, or fire authority to ensure that their building code allows certain multi-family residential buildings up to five stories to be served by a single exit.
Additional requirements to qualify for a single-stairway exit include:
Buildings no more than five stories tall with up to four dwelling units per floor,
Safety features throughout the building, including an automatic sprinkler system and fire resistance and smoke control systems,
Aerial access by the building’s applicable fire department or protection district, and
Buildings constructed of non-combustible or fire-resistive construction materials.
Under this law, the Department of Local Affairs must consult with the Colorado Professional Fire Fighters Association on implementation and data collection regarding single stair buildings constructed in each jurisdiction and the reporting of that data to the legislature during annual SMART Act hearings.
According to a 2025 Pew Study, there has been no evidence of increased safety risks in New York City, Seattle, the Netherlands, and other jurisdictions that allow single stair apartments. Adding a second stairway to an apartment building can increase building costs by 6- to 13-percent, and single stair apartments can reduce cooling costs by up to 80-percent due to improved window placement, which allows cross-ventilation.