Longmont council adopts ordinance to align ADU rules with state law; residents raise concerns about neighborhood impacts

The Longmont City Council on Dec. 16 adopted an ordinance amending Longmont Municipal Code sections governing accessory dwelling units to comply with House Bill 1152, a state law that sets minimum ADU standards for municipalities.

Don Bradshaw, Planning and Development Services, explained that DOLA (Colorado Department of Local Affairs) had identified areas where the city's earlier ordinance was not compliant and that the revised ordinance removes some local restrictions while allowing the city to require that ADU applicants be residents of Longmont. "The state allowed us to make it to where you must be a resident of Longmont in order to build," Bradshaw said, adding that proof of residency may include a Colorado-issued ID and one of several other documents such as a utility bill or voter registration.

During the public hearing, resident Scott Stewart raised affordability concerns, saying that easing ADU construction could encourage investors to add units and raise property values in established neighborhoods: "Developers will eat this stuff up," he told the council, suggesting the change could price out first-time buyers in older neighborhoods.

Several council members acknowledged those concerns while noting the city had limited discretion under the state law. Council Member Marcin and others said they would support the ordinance while urging further conversations with state legislators and additional local policy tools to protect homeownership and neighborhood character. Council Member Marcin said he would vote in favor of the ordinance but urged future discussions to protect land-use and homeownership.

The council passed the ordinance on second reading unanimously; staff and council said they would continue outreach and consider complementary policies to address affordability and resale consequences.