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. Builders must offer buyers of these home types, sprinklers systems, as an option at the buyer’s expense. All homes are required to meet the 2021International Energy Conservation Code (IECC).

All builders under the 2018 IECC, 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. All master models must have approved sprinkler plans to allow for the option of sprinklers.

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.