Case Studies

Where

Gardena, single-family lot.

The project

Convert an existing garage and attached rumpus room, about 460 square feet, into an ADU without expanding the building.

What the city said

In May 2026, planning comments required the structure to meet four-foot rear setbacks and building-separation standards under the city’s ADU ordinance. The reason was the building’s permit history: a 1963 permit for the rumpus room had expired in 1976 without completion, and the area on that old permit did not match the plans. By June the city’s position was that the room first had to comply with current accessory-structure standards before it could be converted. In practice that meant moving or rebuilding the structure, and the owner was told a redesign and rebuild looked like the only route.

What we did

We separated two questions the city had combined: whether the building physically exists, and whether its permit history is complete. State law allows an existing accessory structure to be converted to an ADU (Government Code section 66323(a)(1)) and limits the local standards a city can add; the city’s own ordinance has conversion provisions and limits on denying a project for nonconforming conditions. We supplied assessor records showing the room’s age, asked the project team to hold the rebuild conclusion, and requested technical assistance from HCD in June.

Outcome

In August 2026, HCD responded that the city’s requirement that an existing structure be permitted in order to qualify for conversion was incorrect, citing Government Code section 66322(b) and its health and safety conditions. We sent that response to the planner. Later that month the planner approved planning review and wrote that the disputed comment could be disregarded. The building package was resubmitted in September, on October 21 the plan review came back complete with no further comments, and the building permit has issued.

Status as of October 2026

Building permit issued.

What it shows

The correction read like a code requirement. It was an interpretation. Answering it in writing with the section that controls, and taking it to the State when the city held its position, kept the owner on the conversion route instead of a demolition and rebuild.

Where

Walnut, single-family lot in an R1 zone.

The project

Keep the existing house, legalize an existing detached dwelling as an ADU, and replace the garage with a second primary dwelling under SB 9, plus a new two-car garage, all without splitting the lot.

What the city said

In July 2025, planning staff wrote that because the owner was not pursuing an urban lot split, the property was “only eligible for ADUs/JADUs” and “the opportunity for two primary dwellings is not permissible.” Staff said the issue had been discussed with the City Attorney.

What we did

We responded that SB 9 has two separate parts: a two-unit housing development under Government Code section 65852.21(a), and the urban lot split. The first does not depend on the second, and a primary dwelling under that section is not an ADU. We supplied the statute language, HCD’s SB 9 fact sheet on primary units on a lot that has not been split, and an explanation of how it applied to the mix of existing and new buildings. We did not ask for a waiver or an exception, only that the city evaluate the proposal under the route the statute describes.

Outcome

Later in July, after internal discussion and further guidance from the City Attorney, the planner wrote that the owner could proceed under SB 9, noting it was the first project of its kind in the city.

Then

The owners chose the simpler route and converted the existing dwelling to an ADU. Planning approved that 709-square-foot legalization in December 2025, and building review approved it in 2026.

Status as of October 2026

SB 9 eligibility confirmed in writing; the ADU legalization approved.

What it shows

A written refusal during project discussion is not the end of the question. When the statute says something different from the city’s reading, the fastest path is to put the section in front of the planner and ask for the City Attorney’s review.

Where

Unincorporated Altadena, Los Angeles County, in the Altadena Community Standards District.

The project

Replace the home lost in the Eaton Fire with a single-story house, an attached garage, and a detached ADU placed for privacy. The house sat on the lot differently from the old one and the ADU took an L shape. This was a rebuild shaped around how the family wanted to live, not a reproduction of the lost plan.

The path

Regional Planning cleared the recovery application in July 2025 as a like-for-like rebuild with a detached ADU. Building and Safety accepted the plans for plan check on September 2, 2025.

What the County said

In October, Building and Safety found that the floor areas in the plans, the permit descriptions, and the planning approval did not match, and the figures had changed between submittals. In November the planner cited County Code section 22.04.050, which measures gross floor area from the exterior walls, said earlier approvals had been given as a courtesy, and offered to process the project as a non-like-for-like rebuild.

What we did

We brought the planner and the building staff into one exchange, supplied the earlier planning approval, argued that the project should be reviewed on the baseline the County had already used, and asked for supervisory review. At the same time the design team reworked the site to replace a large retaining wall with balanced cut and fill and a smaller wall, so the house placement still worked.

Outcome

Planning stamped the amended approval in December 2025. Building staff approved the revised plans in early January 2026, and the County issued the building permits on January 30, 2026: 150 calendar days from building plan-check acceptance, with planning work under way before that. Construction followed.

Status as of October 2026

In construction, nearing completion.

What it shows

A modified rebuild can move through the County’s recovery path, but every area figure has to agree across the plans, the permit descriptions, and the planning approval, and someone has to be willing to put all the reviewers in one conversation when they do not.