The Pitkin County Board of Appeals voted to reverse the chief building officials determination that renovation work at 61 Stillwater had crossed the countys 75% thermal-envelope disturbance threshold, and instead granted the appeal conditioned on the applicants committing to a set of envelope- and equipment-improvement measures the applicant proposed in its packet.

Counsel for the applicant, Chris Bridal, and architect Mark Sofield told the board the developer submitted the overall project under an earlier permit and that a detached single-car garage, shared mechanical services and other facts mean the garage should be included in the thermal-envelope calculations. That inclusion, they said, keeps the project under the 75% threshold. The applicants also argued much of the envelope work resulted from unforeseen life-safety and structural defects discovered during permitted demolition and that the county only adopted the 75% threshold after much of the project was underway.

The building department and chief building official presented photographs and recalculations showing wide-scale exposure of envelope components during demolition and concluded that the degree of disturbance exceeded the 75% threshold, triggering new-build energy requirements. Staff also noted that change orders that increase scope are generally held to code in effect at the time the change order is reviewed.

Board members discussed technical issues with multiple experts: which components count in envelope calculations, whether detached or separate structures may be excluded, the timing of permits and code adoption, and the feasibility and cost of meeting HERS (Home Energy Rating System) targets and associated solar requirements. Energy raters and county staff said the house could be improved to a HERS rating near 60 through building-envelope and mechanical work but would require a large additional solar array (roughly 2428 panels, roughly 23 kW estimated by the rater) or off-site solar to reach the countys most stringent new-build target.

Ultimately the board voted to reverse the CBO on condition that the applicant carry out the energy and envelope improvements outlined in the packet (board members referenced "page 55" of the applicants materials during the hearing) and do everything feasible to increase the buildings energy performance. The motion passed by majority vote with one board member dissenting.

The boards decision is case-specific. Staff and applicants were directed to work out how the boards conditions will be translated into permit requirements and inspections before further envelope work proceeds.

The Board of Appeals adjourned after the ruling.