Littleton additions, ADUs and whole-home remodels.

Yes. Littleton is a subject jurisdiction under Colorado HB24-1152, which requires one accessory dwelling unit to be allowed wherever single-unit detached homes are allowed — approved administratively, with no public hearing, on objective standards only. The state law also removes any permanent owner-occupancy requirement and prohibits requiring a deed restriction. Littleton does not require an extra parking space for an ADU within a quarter mile of transit. Littleton’s local implementing ordinance is Ordinance 31-2024, and because these rules are still settling across the Front Range we confirm the current standard with the city on every ADU before we quote it.

The 2024 International Residential Code. Littleton adopted it under Ordinance 11, Series 2025. That is one full cycle ahead of several neighbouring jurisdictions — Lakewood, Centennial, Edgewater and unincorporated Douglas County are still on the 2021 code, and Greenwood Village is on 2018. If your lot sits near a boundary, the applicable code is worth confirming before design starts, because it changes energy, structural and safety requirements.

Usually not, and less often than people expect. Littleton approves minor exterior changes administratively, sends major exterior changes to the Historical Preservation Board, and requires no approval at all for interior work or exterior maintenance. So a kitchen, a basement, a structural interior reconfiguration or a primary suite inside the existing envelope generally does not trigger historic review. Additions and visible exterior changes in the Downtown or Louthan Heights districts do.