Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Ladera Heights
Home additions and ADU construction in Ladera Heights typically runs $45,000 to $130,000 for a standard room addition, while a detached ADU generally lands between $90,000 and $220,000 depending on size and site conditions. If you’re weighing whether to add onto your 1960s ranch or build a new unit over the garage, the first step is knowing which set of county rules applies to your lot. We’ve been pulling permits through LA County Building and Safety for years, which matters more here than almost anywhere else in the metro. Call (877) 610-1318 and Tom or one of his sons will walk you through what’s realistic for your property before you spend a dime.
Why Barrett & Sons Construction Is Ladera Heights’s Preferred Home Additions & ADU Company
Ladera Heights is unincorporated Los Angeles County, not the City of LA. That single fact trips up contractors who spend their days working LADBS permits in Culver City or Inglewood. We don’t. Every addition, garage conversion, and detached unit we build in the 90056 zip code gets permitted through LA County DPW, and we’ve sat through enough county inspections to know what those inspectors flag and what they let slide. It’s procedural fluency that saves you weeks of rework.
Tom Barrett founded this company in 1998 and he still answers the phone. His sons run the crews. When you call about a second-story addition off Slauson or a garage conversion near Ladera Park, you’re talking to someone who will actually stand on your lot and look at your Windows & Doors - Ladera Heights and roofline before quoting a number. We publish our license, our address, and our name. Ask anyone in Ladera Heights who’s had a national outfit quote one price and deliver another bill.
Our Home Additions & ADU Services in Ladera Heights
ADU Design & Permitting
Every ADU in Ladera Heights starts with a county permit. We handle the full design and permitting package, including site surveys that account for the mesa’s slope and the slab-on-grade foundations common to mid-century homes here. If your lot sits along the eastern edge of the neighborhood near the Baldwin Hills oil field, we’ll check for the subsidence issues that experienced Ladera Heights contractors know to look for before penciling a foundation.

Garage Conversion ADU
The ranch and mid-century homes along Don Lorenzo Drive and Mount Vernon Drive often have attached or detached garages that convert beautifully into one-bedroom units. In Ladera Heights, a garage conversion typically runs $30,000 to $80,000, which is the most affordable path to an ADU. Moisture from the marine layer means we pay extra attention to sill plates and drywall at the garage slab before closing anything in.

New Detached ADU
Building a new detached unit in a Ladera Heights backyard will run $90,000 to $220,000, and on some of the deeper lots off La Cienega Boulevard there’s actually room to do it without crowding the main house. We design for the flat and low-sloped roof character of the neighborhood so your new unit doesn’t look like it landed from a different city. Our Roofing in Ladera Heights uses GAF products as our standard on these structures because they hold up to the morning fog better than bargain membranes.

Junior ADU & Interior Conversion
A junior ADU inside your existing footprint is the fastest, least expensive way to add a rental unit in Ladera Heights, often coming in between $45,000 and $90,000 depending on how much plumbing needs to move. We’ve converted spare bedrooms, finished basements, and even oversized utility rooms in the sprawling ranch homes near Ladera Park. County permits still apply, and we pull every one of them.

What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Ladera Heights
When we frame, finish, and waterproof an addition or ADU in Ladera Heights, we use products we can name and that hold their own against the marine layer. Schluter systems go into every wet area we build, and we’ve put GAF membranes on enough Baldwin Hills-adjacent flat roofs to know which ones survive the fog and which ones fail in three seasons. We don’t bring mystery materials off a van. If you want to look up what’s going into your walls, you can do it from your kitchen table while we work.
Common Home Additions & ADU Problems We See in Ladera Heights Homes
- County-vs-city permit confusion. A contractor who pulls a City of LA permit for a Ladera Heights property learns fast that it doesn’t count. We’ve corrected more than one remodel that started with the wrong jurisdiction, and it’s always more expensive than getting it right the first time.
- Post-and-beam structural complications. Many homes here were built with minimal interior load-bearing walls and exposed ceiling beams. Opening a wall for an addition means understanding how the roof actually carries itself, not just hauling out a reciprocating saw and hoping.
- Marine-layer rot at rooflines. The fog that rolls up the Baldwin Hills in the morning isn’t just a visibility nuisance. It accelerates rot at fascias and soffits, and any addition that ties into an existing roofline has to account for the wood condition at the connection point.
- Slab-on-grade foundation surprises. The older slab foundations along the eastern edge of the mesa can show settling from years of oil-field-related subsidence. We survey before we design, because a cracked slab under a new addition is not something you discover after the framing is up.
Pricing for Home Additions & ADU in Ladera Heights, CA
A standard room addition in Ladera Heights runs $45,000 to $130,000. A detached ADU runs $90,000 to $220,000, garage conversions land between $30,000 and $80,000, and a junior ADU inside your existing home starts around $45,000. The biggest variables on a Ladera Heights lot are foundation work, the condition of the existing roof tie-in, and whether your property sits on a slope that requires additional grading or retaining. You’ll get a written line-item quote before any work starts, and if the scope changes, you’ll get a written change order before that work starts. Every number is on paper. Call (877) 610-1318 to schedule a free estimate, and if you already have a written estimate from another contractor, bring it in for a free second opinion.
We Also Serve Cities Near Ladera Heights
Our crews work throughout the Baldwin Hills area, including View Park-Windsor Hills, Culver City, Lennox, and Westmont. If you’re a few blocks outside the 90056 boundary, the county-vs-city permit issue still applies, and we handle both jurisdictions cleanly. You can also learn more about our broader Home Additions & ADU work or see how Ladera Heights fits into our service area. When an addition means reworking the kitchen, our Kitchen Remodeling in Ladera Heights team handles that too, and if you’re adding a new primary suite, take a look at our Bathroom Remodeling in Ladera Heights work.
Serving Ladera Heights, CA - Our Local Coverage Area
We’re based in the Ladera Heights area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Home Additions & ADU in Ladera Heights
County permitting through LA County DPW for an ADU in Ladera Heights typically takes 4 to 8 weeks for plan check, depending on the complexity of your lot and whether structural review is triggered. We handle the full package and keep it moving by submitting correct drawings the first time. Call (877) 610-1318 and we’ll give you an honest timeline for your specific address.
Yes, we work throughout Ladera Heights, including the homes off La Cienega Boulevard, Don Lorenzo Drive, Mount Vernon Drive, and the streets around Ladera Park. No trip charge inside the county means we’ll come look at your property without billing you for the visit.
A second-story addition in Ladera Heights generally starts around $90,000 and can exceed $130,000, while a ground-level room addition often starts around $45,000. The difference comes from the structural work required to carry a second floor on post-and-beam frames and slab foundations that were never designed for vertical load. We’ll give you a written comparison of both options before you commit.
No price changes unless you agree in writing. Every scope adjustment, every allowance overrun, every unexpected condition gets documented as a written change order with a price before the crew proceeds. That’s how we’ve done it since 1998, and it’s why our Ladera Heights customers don’t get surprise bills at the end of the job.
Every job carries our 90-Day Done Right Promise. If something isn’t right within 90 days of completion, Tom comes back and makes it right, one call. On top of that, permits pulled and inspections signed mean the county’s inspectors have signed off on the work. Call (877) 610-1318 for a free estimate and we’ll put the warranty in writing with your name on it.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Ladera Heights and the surrounding counties.







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