A new bill entered the Colorado legislature on Tuesday, aimed at bolstering the state's housing supply through accessory dwelling units. However, there's a crucial detail: most mountain towns won’t be bound by its provisions.

House Bill 1152, if passed, would limit the authority of certain local governments, primarily those along the densely populated Front Range, from restricting homeowners' ability to construct accessory dwelling units, also known as granny flats or mother-in-law suites.

As per the bill's definition, an accessory dwelling unit (ADU) can be within a home, attached to it, or a separate structure on the same lot, equipped for independent living. Proponents believe that by facilitating more ADUs, the housing supply will expand, easing market strains and reducing costs.

However, Colorado's mountain towns, grappling with some of the state's highest housing expenses, will be exempt from the legislation's requirements. Instead, they can "opt into" the program, subject to specific conditions, and may receive incentives such as grant funds outlined in the bill.

Partly, this exemption stems from concerns in rural resort communities that increased ADUs might fuel short-term rental markets while worsening workforce housing shortages.

Sen. Dylan Roberts, D-Frisco, views ADUs as a valuable tool for addressing affordable housing needs in mountain communities, provided they include restrictions to ensure occupancy by local residents rather than tourists.

Rep. Judy Amabile, a Boulder Democrat and sponsor of House Bill 1152, aims to pass the legislation amidst mounting housing challenges, recognizing the urgency over concerns about mountain towns' housing costs.

The bill, following last year's failed housing legislation, Senate Bill 213, is part of a strategy to address housing costs by breaking down legislation into smaller pieces.

If approved, the bill's regulations would apply to communities under metropolitan planning organizations, such as Denver, Boulder, Pueblo, and Grand Junction. It proposes two programs to encourage ADU construction: a grant program to reduce fees and offer technical assistance, and a financing initiative for ADU development.

To qualify for these programs, local governments must be deemed "supportive jurisdictions" by the Colorado Department of Local Affairs, demonstrating compliance with the bill's requirements and strategies for promoting ADU construction.

Sponsored by Rep. Ron Weinberg, R-Loveland, Sen. Kyle Mullica, D-Thornton, and Sen. Tony Exum, D-Colorado Springs, the bill is under review by the House committee on Transportation, Housing & Local Government.