Historic review board offers code clarifications, proposes permit route for small accessory units in McLaughlin Conservation District

The Oregon City Historic Review Board (HRB) and Planning Department presented eight policy recommendations Aug. 12 to clarify how "new construction" and additions are measured in the McLaughlin Conservation District and to create a path for small, compatible accessory dwelling units (ADUs) to be permitted through the building-permit process rather than a Type 3 historic-review hearing.

Planning staff described the project background, outreach and the draft recommendations. Staff said the McLaughlin Conservation District includes about 854 properties, of which roughly 553 are non‑designated historic resources and 301 are designated. Current code treats any new building or structure larger than 200 square feet as "new construction" subject to HRB review; additions that increase a building's area by 30% or more (individual or cumulative) also trigger review.

Staff proposed changes the board developed after monthly work sessions and community outreach, including postcards, a March 2025 open house and an online survey. Key recommendations presented to the commission: - Look‑back provision: a two‑year look‑back to ensure owners do not split work to avoid historic review (staff said the board discussed two and five years and settled on two as reasonable). - Clarified measurement rules: use the city’s footprint definition for consistent 30% addition calculations, and cap the 30% calculation at 700 square feet for very large buildings. - Deck treatment: ground-floor decks would be exempt from the 30% addition calculation; upper-story decks would be capped at 50 square feet for exemption, with larger balconies counted toward the 30% test; staff noted that exterior stairs connected to an upper deck would commonly trigger review and should be clarified. - Height/massing: staff recommended retaining review for meaningful changes in roof height (the HRB recommended allowing only small tolerances of a few inches for routine repairs) and clarified that massing concerns remain a key compatibility tool. - Incentivized permit pathway for small dwelling units: a proposed HRB Policy 13 would allow certain small new dwelling units (suggested thresholds: single‑story, under ~600 square feet, limited materials/roof pitch and other objective design limits) to proceed by building permit rather than a Type 3 HRB review if they check a compatibility checklist. - Accessory building threshold: raise the non‑habitable accessory‑building threshold from 200 square feet to about 310 square feet to permit a contemporary single‑car garage without triggering full historic review.

Board members and commissioners supported the basic direction but asked staff to clarify technical elements. Commissioners and HRB members suggested adding minimal illustrative diagrams to the public materials and code guidance so property owners can visually understand what triggers review (for example, what constitutes "massing" changes or a covered versus an uncovered deck). Mayor Denise McGriff and other commissioners emphasized clarity for frontline staff and applicants, and asked staff to ensure that definitions and measurement methodology reduce ambiguity.

What happens next: Staff said that if the commission gives direction to proceed, the HRB will finish drafting HRB Policy 13 and staff will prepare red‑lined code amendments for public hearings and formal legislative processes. Staff said the Planning Department will return to the commission before starting the legislative hearings to show proposed language and supporting illustrations.

Ending: The commission agreed to move the project forward; staff will develop the policy and code red lines this fall and return for review and hearings.