Fort Collins, CO Building Safety: Carbon Monoxide Detectors (2026)

City Code Sec. 2, Alterations, repairs and additions, to require that where a permitted alteration, repair, or addition occurs, or where one or more sleeping rooms are added or created in an existing dwelling, the individual dwelling unit must be equipped with carbon monoxide alarms located exactly as required for new dwellings. Fort Collins goes further than the base model code by deleting the exceptions that would otherwise excuse certain smaller-scope work from the retrofit trigger, meaning any permitted alteration, repair, or addition project in the city brings the CO alarm requirement into play, not just larger-scope work.

4, Interconnection, which requires that where more than one smoke alarm is required within a dwelling unit, the devices must be interconnected so that one alarm activating triggers all alarms in the unit, with an exception for existing areas where interconnection would require removing interior wall or ceiling finishes without attic, crawlspace, or basement access. Together the two sections push retrofit projects toward the same alarm coverage and interconnection standard required in new construction. Compliance is verified by CDNS during the permit inspection tied to the triggering alteration, repair, addition, or bedroom-creation project; the alarms and their required locations follow the placement standards set for new dwellings elsewhere in the residential code's alarm sections.