Get Full Government Meeting Transcripts, Videos, & Alerts Forever!
Get email alerts on the Housing Adu topic
No spam. Unsubscribe anytime.
Boulder BOZA approves 126-sq-ft variance to allow 477-sq-ft ADU on substandard R-1 lot
Summary
The Boulder Board of Zoning Adjustment approved a building-coverage variance (BOZ2026-00005) allowing about 126 square feet over the code limit so the owners can place a 477-square-foot detached ADU on a 6,227.9-square-foot R-1 lot. Staff raised concerns about whether alternatives were fully explored, but a majority of the board found the site conditions and design justified approval.
The Board of Zoning Adjustment voted to approve BOZ2026-00005, a building-coverage variance for the property the staff identified in the hearing as 2910 5th Street, to permit a detached accessory dwelling unit (ADU) that increases building coverage by about 126 square feet. The motion to approve was moved by board member Drew and seconded by Jill; the board recorded affirmative votes and the chair announced the application approved.
Staff planner Robbie told the board the surveyed lot is about 6,227.9 square feet and the land-use calculation for the site produced a maximum allowable building coverage of roughly 2,295 square feet. The applicant's existing building coverage was reported at about 1,944 square feet and the proposed coverage, including the detached ADU, was presented as about 2,421 square feet, producing a variance request of about 126 square feet. Robbie said staff had questions about whether all variance criteria were satisfied, particularly whether alternatives had been shown that would avoid the variance: "We weren't necessarily sold that that was a true hardship," he said, noting staff had highlighted concerns under H1C and H5C of the code.
The applicant team, represented by design consultant Lisa Larson and architect Steven Sparn, said the ADU is a modest, standardized modular unit (about 477 sq ft) intended to meet an aging-in-place and family-housing need and that the lot's grade and an elevated rear deck make straightforward alternatives impractical. Sparn argued the slope causes the deck to count as building coverage and thus produces a site-specific effect on the coverage calculation: "The issue is the coverage calculation is being affected by existing site conditions, necessary open exterior access elements, and technical code thresholds," he said, and urged that the requested relief would not meaningfully harm open space, sky access or privacy.
Board chair Katie said she was persuaded by the applicant's presentation: "I am pretty persuaded that they have met H1A and H1C," she said during deliberations. Several other members echoed that view after probing whether the front porch or deck could be modified to avoid the variance. The board ultimately voted to approve the variance. The staff noted that the project remains subject to an active building permit review (BLDACC2026-00004) and that floor-area, height and solar-access standards will be verified during permit processing.
What happens next: The approval authorizes the variance but does not finalize building permit approvals. The applicant must complete the active building-permit review and any conditions of approval identified by staff; neighbors and the city will continue to have opportunities to review permit-level details.
