Rio Grande County inspector outlines phased energy-code rollout; Monte Vista enters phase 2

Randy Kern, Rio Grande County building inspector, told the Monte Vista City Council that the region is entering phase 2 of a phased implementation of updated building and energy codes adopted after state law changes.

“We are just beginning phase 2 of the implementation,” Kern said, describing steps that will be added to the city’s code enforcement and permitting process, including whole-house mechanical ventilation and air-leakage testing prior to occupancy.

Why it matters: Kern said the phased approach moves jurisdictions from older energy rules toward the 2018 suite of I-codes while giving builders time to comply. Phase 1, already in effect since July 2023, focused on building-envelope improvements such as air barriers and flashing. Phase 2 adds mechanical ventilation requirements and blower-door testing; Kern said the code requires a maximum of three air changes per hour but that Monte Vista will accept up to five air changes per hour during this phase to allow builders time to adapt.

Kern described the mechanics of the testing: a third-party blower-door test measures air changes per hour at the final inspection, and the city will also begin verifying that heating and cooling equipment is sized correctly using established software programs. He said the final phase would lower the acceptable air leakage rate from five changes per hour to three.

Kern also answered questions about manufactured housing and modular units. He noted that HUD-code manufactured homes and factory-built modulars are regulated through the state Division of Housing and in many cases are not inspected under local codes in the same way as site-built homes. Kern said tiny homes remain a regulatory issue and that the Division of Housing’s certification program for tiny homes had not yet certified manufacturers at the time of the briefing.

Kern said upfront costs for compliance will rise because of additional requirements and equipment but said experts expect energy-bill savings over time. Council members asked about timing and enforcement; Kern said phase 2 work was just beginning and that the full phase-3 timeline will be revisited depending on field experience and the busy construction season.

Ending: Kern urged patience as the phased rollout continues and said city staff and Rio Grande County would provide guidance to builders and contractors as inspections and verification steps ramp up.