Boulder County officials have proposed new rules that would permanently limit the size of homes in unincorporated parts of the county, marking the county鈥檚 latest effort to try to curb rising housing costs and reduce the environmental impact of large homes.
The , released for public comment Feb. 26, would amend the county鈥檚 site plan review process to prohibit new homes from exceeding the median size in their respective neighborhoods, with some exceptions. If approved, the rules would make permanent a , when county commissioners enacted a six-month moratorium on the construction of homes above the neighborhood median.
Before the moratorium, county regulations allowed new homes to be built up to 125% of the median size for a given neighborhood, with an option for special approval to go even larger. According to county commissioners, this policy has contributed to a steady increase in the size of homes in recent years. Last year, multiple applications were submitted for homes exceeding 6,000 square feet.
A is to help reduce the cost of housing, according to county commissioners. Larger, more expensive homes can increase property taxes for other, more modest homes in a neighborhood. Large homes can also contribute to higher overall housing costs.
By capping new homes at 100% of the neighborhood median, 鈥測ou will see smaller houses than you would have otherwise, which will have a lower impact on the environment and can have effects on affordability and neighborhood character,鈥� Commissioner Ashley Stolzmann told Boulder Reporting Lab.
Stolzmann said the changes are also intended to streamline the review process, making it more predictable and reducing application processing times.
The county may allow exemptions for properties with conservation easements that permit larger homes or for homes that include landmarked or protected, historic structures. Property owners looking to expand beyond the new limits for energy-efficiency retrofits could also qualify for an exemption. Homes lost in the 2021 Marshall Fire would be rebuilt under regulations in place at the time of the fire, following a separate disaster recovery.
The proposal is expected to face opposition from businesses in the home construction industry, including builders, architects and property owners who had planned to build homes larger than the new rules allow. Dozens of residents testified against the initial moratorium.
Some architects have raised concerns that tying home size limits to neighborhood medians benefits homeowners in wealthier areas, where houses tend to be larger. Because the policy allows for expansions relative to existing home sizes, those in more affluent neighborhoods can build even bigger homes, while residents in areas with smaller homes face stricter limits. Critics argue this disparity could accelerate property value appreciation for wealthier homeowners at a faster rate than for those who are less wealthy.
To address this, county planners have proposed a sliding scale that would allow existing homes in neighborhoods where the median home size is relatively small. Under the proposal, owners of homes 1,500 square feet or smaller could expand by up to 1,000 square feet or to the neighborhood median, whichever is greater 鈥� potentially exceeding the 100% cap. On the other end of the scale, homes up to 4,500 square feet would be limited to an additional 675 square feet or the median, whichever is greater.
Brian Fuentes, an architect with the local passive home design and build firm, said the change still favors homeowners with larger houses.
鈥淭hey are only stopping big houses where there are not big houses now, which is essentially just putting the burden on people who have less,鈥� Fuentes told Boulder Reporting Lab.
Instead of tying home size limits to neighborhood medians, he suggested the county adopt more granular zoning that sets limits based on factors such as road and water access. He also suggested imposing a fee on larger homes to help fund affordable housing.
A public hearing before the county Planning Commission is scheduled for March 19. The Board of County Commissioners will host a subsequent hearing before finalizing the rules.
John Herrick is a reporter for The Boulder Reporting Lab. His work frequently appears on-air at KUNC 91.5 FM and online at KUNC.org. Contact John at john@boulderreportinglab.org.