Commission presses staff for clear conversion path for existing accessory structures into ADUs

During deliberation on the ADU ordinance, commissioners focused on how to let homeowners convert preexisting accessory buildings (garages, barn-like structures) into habitable ADUs without undermining setback protections for neighbors.

Commissioners agreed to direct staff to draft language that would allow a portion of an existing accessory structure that encroaches into a required setback to remain as non-habitable space (storage, closets, garage), while permitting the remainder of the structure — located outside the setback and meeting building-code requirements — to be converted to habitable ADU space. Staff emphasized conversions must meet building and fire codes, and the commission asked that conversions from structures built before the ordinance date be limited to single-story habitable areas where proximity to property lines is close.

Todd Vanderlinden, a public commenter, urged such a path to help homeowners create multigenerational housing without requiring costly demolition or full rebuilds. "It does not make sense to knock the structure down," he said of his example garage. Staff will return with specific draft language that identifies the allowable non-habitable perimeter depth, references building-code/fire-safety metrics (e.g., protected openings and firewall requirements), and clarifies how footprint and lot-coverage calculations apply to converted structures.

The commission’s direction is intended to comply with state law while avoiding an outcome that forces homeowners to demolish otherwise legal accessory buildings or to create unsafe or over-dense conversions.