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 ADUs in Ladera Heights typically run $45,000 to $130,000 for an addition and $90,000 to $220,000 for a new detached ADU, with county permitting adding steps most contractors miss. Ladera Heights is unincorporated LA County, which means every permit goes through LA County Building and Safety, not LADBS. That distinction catches a lot of crews off guard. Ours doesn’t. If you’re planning a room addition, second story, or ADU in Ladera Heights, call Barrett & Sons Construction at (877) 610-1318 and we’ll walk the property with you before any number goes on paper.
Tom Barrett founded this company in 1998 and built it around one idea: a name on the truck means something. We’re not a franchise handing your project to whoever picks up the phone. Tom and his sons run the crews that work in Ladera Heights, and every price change arrives as a written change order before a single nail moves. That’s how we’ve kept customers in ZIP code 90056 coming back for over 29 years.
Why Barrett & Sons Construction Is Ladera Heights’s Preferred Home Additions & ADU Company
We know Ladera Heights the way you know your own street. The homes here aren’t Levittown boxes. They’re custom and semi-custom mid-century builds from the 1950s through the 1970s, many with post-and-beam frames, slab-on-grade foundations, and flat or low-sloped roofs. Before we quote an addition on a 1964 ranch off La Brea Avenue or a detached ADU near Ladera Park, we look at how that house was actually built. Structural load analysis for post-and-beam framing is different from platform framing. Slab-on-grade foundations need different tie-in details. Flat roofs need membrane checks before we attach anything to them. A contractor who works primarily in Culver City or West Los Angeles might not flag these things. We do, because we’ve been pulling permits through LA County for years.
Reviews from Ladera Heights customers mention the same things: the crew showed up when they said they would, the change order process kept everyone honest, and the county inspector signed off without drama. Tom Barrett publishes his name, address, and license number. Call him. Look him up. Ask anyone on your street. The Home Additions & ADU team that works in Ladera Heights answers the phone with a live person, 24 hours a day. Not a voicemail box, not an out-of-state call center.
Our Home Additions & ADU Services in Ladera Heights
ADU Design & Permitting
Every ADU in Ladera Heights starts with LA County Building and Safety, and county reviewers enforce different setback, septic, and grading standards than the City of LA. Our design and permitting service handles the full package: site plan, floor plan, structural drawings, Title 24 energy compliance, and county submittals. We pull the permit. We schedule the inspections. When the county wants a soils report because your lot sits near the Baldwin Hills subsidence zone, we order it and factor it into the scope before quoting.

New Detached ADU
Building a new detached ADU in Ladera Heights means starting with the land itself. Grading and drainage come first, especially on open mesa lots where county stormwater rules apply. If you have a septic system, the new ADU’s field must sit clear of the existing well and any recorded subsidence zones along the eastern edge of the neighborhood. We scope all of this before we give you a number. A detached ADU in Ladera Heights generally runs $90,000 to $220,000 depending on size, finish level, and how much site work your lot requires.

Garage Conversion ADU
Converting a garage to an ADU in Ladera Heights often works well because many of these homes have detached garages with usable footprints. The questions are structural: Is the existing slab sound? Does the roof need a membrane replacement before we tie in new framing? Does the county require a soils report for this specific parcel? We answer all of that during the estimate, in writing. Garage conversions in Ladera Heights typically run $30,000 to $80,000.

Junior ADU & Interior Conversion
A junior ADU, or JADU, converts existing interior space, like a large den or a portion of the primary bedroom suite, into an independent living unit. In Ladera Heights, where many 1950s and 60s homes have generous room sizes, this can be the fastest path to rental income or multigenerational housing. County review for JADUs is typically lighter than for detached units, but we still handle every form and every inspection.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Ladera Heights
We stock and install materials we’d put in our own homes. For ADU kitchens and baths, that means Schluter systems for waterproofing, Sterling and Grohe fixtures where the spec calls for them, and GAF roofing products when we’re tying a new ADU roof into an existing flat or low-sloped roof or replacing a membrane on a 1960s original. We know the material lead times for Ladera Heights jobs because we order from the same local suppliers month after month. If you want to look up the brand before we install it, please do. We’ll give you the model numbers before work starts.
Common Home Additions & ADU Problems We See in Ladera Heights Homes
- Wrong jurisdiction permits. A contractor pulls a permit through LADBS out of habit, then gets stopped at the first county inspection because the forms, setbacks, and review standards are wrong. This delays the job weeks, sometimes months. We pull through LA County Building and Safety from day one.
- Structural surprises on mid-century frames. A bid assumes a standard platform frame, but the house is 1958 post-and-beam on a slab. The addition needs a structural engineer’s load analysis and different tie-in details. We catch this during the walkthrough, not after demolition.
- Drainage and grading on an open mesa lot. Ladera Heights sits on the Baldwin Hills mesa. County stormwater rules apply, and marine-layer moisture accelerates rot at fascias and soffits. We sequence grading and drainage before rough-in on every open-lot addition.
- Baldwin Hills subsidence concerns. The oil field directly east has caused measurable ground subsidence for decades. On slab-on-grade homes along the mesa’s eastern edge, we recommend a foundation inspection before committing to an addition scope.
Pricing for Home Additions & ADU in Ladera Heights, CA
A home addition in Ladera Heights runs $45,000 to $130,000. A garage conversion runs $30,000 to $80,000. A new detached ADU runs $90,000 to $220,000. What moves the number? County permit and soils report requirements, septic and well setbacks on rural-style lots, grading and drainage scope, structural upgrades to mid-century post-and-beam frames, and finish level. Here’s the line-item breakdown:
| Project Type | Typical Ladera Heights Range |
|---|---|
| Home Addition | $45,000 - $130,000 |
| ADU Construction | $90,000 - $220,000 |
| Garage Conversion | $30,000 - $80,000 |
Every estimate includes a written line-item scope. Every change after that is a written change order signed before work proceeds. No surprises at the end. Call (877) 610-1318 for a free estimate on your Ladera Heights addition or ADU. We also offer a Free Second Opinion on any written estimate you’ve received, and if you’re 55 or older or a veteran, ask about our permanent 10% discount.
We Also Serve Cities Near Ladera Heights
Our Home Additions & ADU in Ladera Heights crews also cover View Park-Windsor Hills, Culver City, Lennox, and Westmont. If you’re on the edge of the mesa in any direction, call and ask. We’ll tell you straight whether we can get to your job this month.
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
Ladera Heights is an unincorporated community, so all construction permits are issued by LA County Building and Safety (DPW), not LADBS. County reviewers enforce different setback, septic, and grading standards than the City of LA. A contractor who works mostly in city limits may not know which county forms to file or which soil and drainage reports the county requires. We do. Call (877) 610-1318 and we’ll explain exactly what your project needs before you spend a dollar.
If your lot has a septic system or a well, the county requires the new ADU’s foundation and septic field to sit clear of both by specific distances. On a smaller Ladera Heights parcel, that can shape the entire site plan before architectural drawings begin. We map setbacks, order the soils report when the county asks for one, and sequence site prep, grading, and drainage before rough-in so the foundation inspection passes the first time. Estimates are free, so call (877) 610-1318 to talk about your lot.
Post-and-beam framing carries loads differently than standard platform framing, so any addition needs a structural engineer’s load analysis and custom tie-in details at the roofline and foundation. Many Ladera Heights homes also sit on slab-on-grade foundations, which means the new addition’s slab and footings must be designed to match. We bring the engineer in during scoping, not after we open the wall. Call (877) 610-1318 for a walkthrough.
Ladera Heights sits on the Baldwin Hills mesa and gets more morning fog and marine-layer moisture than the flats below, which means a sunroom or enclosed patio addition needs proper drainage at the roof tie-in and rot-resistant detailing at any existing fascias or soffits it touches. If the existing flat roof is original, we recommend a membrane check before we attach new framing. Better to replace it before it fails under the new wall ties than after. Call (877) 610-1318 and we’ll take a look.
Often, yes. Many Ladera Heights garage slabs are in workable condition, especially on the custom builds from the 1960s and 70s. The decision depends on a slab inspection, the roof condition, and whether the county requires a soils report for your specific parcel. We give you a straight answer during the estimate, in writing, with the engineer’s input when needed. Call (877) 610-1318 to schedule yours.
Call Barrett & Sons Construction for Your Ladera Heights Addition or ADU
If you’re reading this, you’re probably tired of contractors who quote one number and deliver another. That’s not how we work. Tom Barrett’s name, address, and license number are published and verifiable. Every scope, allowance, and price change arrives in writing before work happens. Every eligible job gets permits pulled and inspections signed. And every completed job is backed by our written 90-Day Done Right Promise: if it’s not done right, Tom comes back and makes it right, one call.
Schedule your free estimate for a home addition or ADU in Ladera Heights. Call (877) 610-1318. A live person answers.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Ladera Heights and surrounding LA County communities.







Before
After
Before
After
Before
After