Commerce City updates Residential Building Code requirement

Published on December 08, 2025

Effective Nov. 17, Commerce City implemented an amendment to the 2021 International Residential Code that makes residential fire sprinkler systems optional for all new single-unit homes, duplexes, and townhome construction.

This change follows the requirement outlined in Colorado Revised Statutes (C.R.S.) sec. 31-15-602(3.5)(a), which mandates that any municipality updating building codes between July 1, 2023, and July 1, 2026 must adopt and enforce the 2021 International Energy Conservation Code (IECC), the model electric code, and the solar-ready code.

As part of these updates, all builders are required to submit revised plans, update energy certification documentation, and/or revised Manual J, D, and S materials for all master models before any electrical, mechanical, or insulation inspections can occur.

Permits that were issued before Nov. 17 will continue to follow the requirements in place at the time they were issued. For questions or assistance with these updates, contact the Building Permits Division at cdpermits@c3gov.com or call 303-289-3790.