ADUs & Additions in Los Alamitos

City of Los Alamitos Development Services Department, Building and Safety Division. Residential permits are issued by the Building and Safety Division at City Hall, 3191 Katella Avenue, and applications, PDF plan uploads, fee payments and inspection requests can all go through the city's online Building Permit Center; since January 1, 2026 the city has enforced the 2025 California Building Standards Code with local amendments. Demolishing an in-ground pool or spa requires a permit: the top 18 inches of pool wall come out, holes are drilled through the bottom, the shell is filled with sand, compacted dirt or material specified by a soils engineer, and two inspections follow, with a certified compaction report from a soils engineer required if the area will be built on. For ADUs, the city offers two pre-approved one-story, all-electric plans, a 563-square-foot one-bedroom and an 876-square-foot two-bedroom, which still need some site-specific design work and a separate permit for the solar photovoltaic system. We prepare the drawings, make the submittal and handle plan-check corrections ourselves, so you are not the one chasing plan check.

Flat, essentially built-out ground, where the Joint Forces Training Base on the southeast side takes up roughly half of the city's land. The rest is divided among 16 neighborhoods whose housing ranges from small and large detached homes to townhomes and medium- and high-density apartments, so new work here usually means reshaping an existing lot rather than building on open land. One local condition that shapes the work: The city sits on quaternary deposits of alluvium and colluvium, with soils mapped as Bolsa silt loam, Hueneme fine sandy loam and Metz loamy sand among others, and the city's Housing Element review notes a characteristically high water table and cohesionless subsoils in some areas that may liquefy during extreme ground shaking, so a soils investigation belongs at the start of any pool shell or ADU foundation design.

All of it, including Carrier Row, Old Town West, Dutch Haven and Rossmoor Highlands. Our crews run every job out of our Cahuenga Pass base in Los Angeles, with our own people on site.

Detached ADU: generally $150,000 to $400,000+ across Southern California. What moves it is square footage, finish level, utility runs, and site access; garage conversions typically run well below a ground-up detached build. We give line-item pricing after seeing the site rather than quoting a number over the phone.

Plan a realistic year. Design and engineering typically take one to three months, city plan check and corrections add several more, and construction usually runs four to eight months depending on size and site access.

Usually yes, and often substantially, because the foundation, walls and roof already exist. The trade-offs are that you lose the garage, and older slabs and framing sometimes need upgrading to meet current code.

California ADU law is designed to allow long-term rental, and an ADU is one of the few ways to add rentable square footage to a single-family lot. Short-term rental rules vary by city, so confirm your local ordinance before counting on that income.

Yes. Plans, engineering, Title 24 and the city submittal are all handled in-house, including responding to plan-check corrections. That is a service we sell on its own, so it is not something we hand off.