ADU Construction in Los Angeles and Orange County

Most single-family lots in California can generally have an attached or converted ADU, a detached ADU, and a JADU. A detached ADU gives you the most privacy and the most flexible layout. State law commonly allows detached units up to 1,200 sq ft, with side and rear setbacks commonly as small as 4 ft. An attached ADU shares a wall with the main house and is capped relative to the size of your home. If you already have a garage, a garage conversion is often the fastest and least expensive route, because the slab, walls, and roof are already there. A JADU carves up to 500 sq ft out of your existing home. Local rules vary, so KR confirms what your specific lot allows during feasibility.

We start with a site visit. We look at lot size, setbacks, utilities, access for equipment, slope, and any overlay zones like hillside or fire zone rules. Then we coordinate design, structural engineering, and Title 24 energy work, and submit plans to the right building department. In the City of Los Angeles, that means LADBS, which also offers a Standard Plan Program with pre-approved ADU designs. Burbank, Glendale, Pasadena, and cities in Orange County run their own departments. Once permits are issued, we build, schedule every inspection, and close out the permit at final. Our ADU guide walks through each step in more detail.

State law has made ADUs easier to build. There is no owner-occupancy requirement for ADUs under AB 976, and starting in 2026, JADUs with their own bathroom no longer require owner occupancy either. ADUs 750 sq ft or smaller are exempt from impact fees. Cities must act on a complete ADU application within 60 days. AB 2533 opens a path to legalize some older unpermitted units, and AB 1033 lets cities opt in to allowing ADUs to be sold separately as condos, so check your city's current status. On multifamily lots, SB 1211 allows more detached ADUs, up to 8 but not more than the number of existing units. These are general rules. Your city may add its own standards, and we check them for your address before design starts.

In Los Angeles, design and permitting commonly take 2 to 6 months. Construction of a detached ADU commonly takes 4 to 8 months after permits are issued. Garage conversions usually move faster. Costs vary with size, site, and finishes. A garage conversion often lands in the low six figures, while a larger detached new-build ADU is commonly in the mid six figures. KR gives you a written estimate after a site visit, so the number reflects your lot and your plans. If you are in the Valley, see how we work in Sherman Oaks, or request a free estimate to get started.