Planning commission approves ADU siding exception for 258 Rainbow Lane, with conditions

The Pleasant Hill Planning Commission voted May 12 to approve a use permit allowing nonconforming cement-board vertical siding on a detached accessory dwelling unit (ADU) at 258 Rainbow Lane, with conditions to correct several other noncompliant items.

Andrew, planning staff, told the commission the ADU is a 933-square-foot, factory-built structure installed after permits were issued but before final inspections and a certificate of occupancy. "The ADU has been installed, but final inspections and permits have not been issued yet," he said, and staff identified several nonconforming elements: exterior siding that does not match the stucco primary residence, fascia and column finishes, front door color, downward-facing light fixtures and a set of stairs that encroaches into the side-yard setback.

Staff said the manufacturer shipped the premanufactured unit with vertical cement-board siding because the factory could not apply stucco in transit. The applicant’s representative, Tatum Maguire (speaking for homeowner Colleen Wilson), said the homeowner preferred the siding and that multiple features flagged by staff were addressed before the hearing. "We would like to keep the cement board siding in place of the stucco," Maguire said. She also told the commission the homeowner was willing to paint trim, change the door color if required and remove the side-yard stairs if the commission required it.

Commission discussion focused on two tensions: the city’s architectural standards for class 2 ADUs (structures over 800 sq ft) that require exterior materials to match the primary residence, and the city’s broader housing goals that encourage ADU construction. Commissioners noted that a class 1 ADU (800 sq ft or smaller) would not be subject to the same architectural standards. Several commissioners said they found no health- or safety-related impacts that would require denial and emphasized that the stair encroachment must be corrected prior to final occupancy.

The commission moved to adopt the staff-recommended resolution and voted to approve the use permit, with the record showing unanimous support. The approval was conditioned on correcting the listed nonconforming items (trim/fascia/door color, light fixtures) and removing the stairs that encroach into the required side-yard setback; staff will verify compliance before issuing a certificate of occupancy.

The commission also asked staff to consider whether the city’s ADU standards need clarifying for prefabricated or factory-built units to reduce future surprises for applicants and staff.