Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
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AfterFast, Reliable Home Additions & ADU Across West Hollywood
Home additions and ADU construction in West Hollywood typically run $45,000-$130,000 for a full addition and $90,000-$220,000 for a detached ADU, with garage conversions landing in the $30,000-$80,000 range. The bigger variable in WeHo isn’t labor or lumber, it’s the permit path. West Hollywood runs its own building department, its own plan check queue, and its own inspector roster, so a contractor who quotes you off LADBS assumptions is pricing the wrong job. Call (877) 610-1318 and we’ll walk the lot with you before anyone talks square footage.
Why Barrett & Sons Construction Is West Hollywood’s Preferred Home Additions & ADU Company
We’ve built on tight West Hollywood lots where the staging area is a single parking space and the neighbors are six feet away, not sixty. That changes how you sequence a job, where materials live for eight weeks, and how loudly you can swing a hammer before the city’s noise ordinance gets called in. Our crews know the street geometry between Santa Monica Boulevard and the hillside lots north of Sunset, and we schedule deliveries so a flatbed isn’t blocking a shared driveway at 7 AM.
Tom Barrett puts his name, address, and license number on every contract, and his sons run the crews that show up in West Hollywood. Every scope, every allowance, and every price change arrives as a written change order before work happens. No surprise invoices. No “we’ll figure it out at rough-in.” That’s why homeowners in the 90069 zip keep our number: they’ve already been burned once by a national outfit that answered the phone in another state and sent a stranger to their door.
The West Hollywood permitting layer is real. We’ve pulled permits through the city’s own plan check enough times to know which reviewers want structural calcs on a garage conversion and which ones flag egress drawings on a junior ADU. That relationship with city staff isn’t something a franchise can fake, and it’s the difference between an ADU that takes five months and one that sits in review for a year.
Our Home Additions & ADU Services in West Hollywood
ADU Design & Permitting
Every ADU in West Hollywood starts with the city’s own permit queue, not LADBS. We handle the full design package, structural drawings, soils reports where the hillside lots require them, and the RSO notices that multi-unit properties trigger. The permit inspector works for you, not for me, that’s why we like him. We walk each submittal through plan check in person and fix comments before they become stop-work orders.
Garage Conversion ADU
Garage conversions are the most common ADU type in West Hollywood because the dingbat apartments and courtyard bungalows already have the footprint. Around $30,000 to $80,000 gets you a legal unit where a tuck-under garage used to collect junk. On a 1940s courtyard complex near the 90069 zip, our crew handled a garage conversion with galvanized plumbing and knob-and-tube wiring under the original subfloor. We staged materials in the narrow alley, kept the shared driveway clear for tenants, and pulled a separate West Hollywood building permit before any rough-in. The inspection sign-off came from the city’s own inspector.
New Detached ADU
A detached ADU in West Hollywood usually means building in a back corner of a lot that was never meant to hold another structure. Setbacks, utility trenching, and soils on the northern hillside-adjacent streets all affect the quote. New detached ADUs here run $90,000 to $220,000 depending on site access and foundation work. We handle the full scope: ADU site prep, trenching, tie-in to existing water and sewer, and the separate meter if you want the unit rentable.
Junior ADU & Interior Conversion
A junior ADU converts existing space inside the main dwelling, usually a bedroom with its own exterior entrance. It’s the fastest ADU type in West Hollywood and the cheapest route to a legal unit because you’re not adding square footage. But on a courtyard bungalow with shared walls, a JADU conversion can legally require written notice to multiple adjacent units under the city’s tenant-habitability rules. We handle those notices so you don’t learn about that requirement at plan check.
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 West Hollywood
We install products you can look up, not mystery brands off a van. On West Hollywood additions and ADUs, that means Simonton and Ply Gem windows on the exterior envelope, plus PGT impact products where hillside exposure or newer code cycles call for it. We stock common trim, flashing, and window components for West Hollywood jobs so a measurement mistake on a 1950s dingbat opening doesn’t stall the whole rough-in for a week. Our Home Additions & ADU team brings the same brand discipline to every opening we cut, every header we spec, and every final walkthrough. We’re proud to be the local team serving West Hollywood with straight pricing and named products.
Common Home Additions & ADU Problems We See in West Hollywood Homes
- Unpermitted previous work. We frequently open up walls in 1920s courtyard bungalows and find a bathroom or sunroom that was never permitted. West Hollywood’s own building department will flag that on a new ADU permit and the fix is always more expensive than starting legal.
- Soft-story retrofit conflicts. If your 1950s or 1960s dingbat apartment hasn’t completed the city’s mandatory seismic retrofit, a second-story addition can be denied outright. The retrofit has to come first or the structural engineer has to justify an exception.
- Party-wall notices on shared-wall properties. A single garage conversion in a courtyard bungalow complex can trigger written notice requirements to multiple adjacent units under West Hollywood’s tenant habitability rules. Skip that step and you’re looking at fines, not just delays.
- Expansive clay soil movement. Nearly zero rain from May through September causes the clay soils on hillside-adjacent northern lots to shrink and crack, then heave when winter rains return. That cycle stresses slab foundations and routinely triggers soils engineering requirements on any ground-disturbing permit.
Pricing for Home Additions & ADU in West Hollywood, CA
Here’s what we’re actually seeing on West Hollywood jobs right now. These are all-in ranges that include labor, materials, permits, and our written change order process. Final cost moves with site access, soils conditions, foundation work, and the scope of utility upgrades. We don’t quote a number on the phone and show up with a different one. What we quote is what you sign.
| Project Type | Typical West Hollywood Range |
|---|---|
| Home Addition | $45,000-$130,000 |
| ADU Construction | $90,000-$220,000 |
| Garage Conversion | $30,000-$80,000 |
Room additions on West Hollywood’s rare single-family lots lean toward the lower end. A full second-story addition on a dingbat apartment that needs seismic retrofit work first will push toward the top. Get a written line-item quote. Call (877) 610-1318 and we’ll walk your lot, look at access, and give you a real number in writing.
We Also Serve Cities Near West Hollywood
Our Home Additions & ADU crews cover West Hollywood and the surrounding area, including Beverly Hills, Century City, Hollywood, and Universal City. Each city has its own permit path, and we carry the right local knowledge for each one. If you’re close by, ask us about the free second opinion offer.
Serving West Hollywood, CA - Our Local Coverage Area
We’re based in the West Hollywood 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 West Hollywood
Yes. West Hollywood runs its own building department and its own plan check queue, separate from LADBS. An LADBS-approved addition on your property does not carry over as approved work under West Hollywood’s code. You’ll need a separate West Hollywood permit for any new ADU or addition, and the city’s own inspector will be the one signing off. Plan for that from day one. Call (877) 610-1318 and we’ll pull the right permit the first time.
It means your ADU permit will almost always require work to proceed with rent-controlled tenants still in place, plus written notice to tenants and often relocation plan requirements. That’s a compliance layer that Beverly Hills or unincorporated LA projects don’t face. We handle the notices, the tenant communication plan, and the construction phasing so the work stays legal and the tenants stay put.
Usually no. West Hollywood’s mandatory soft-story retrofit program targets the dense stock of 1950s and 1960s dingbat apartments, and the city can deny or condition your addition permit on completing that seismic upgrade first. The retrofit is a separate permit track, and in practice many second-story additions in WeHo can’t move until the retrofit is done or an engineer justifies a code-compliant exception. Get clarity before you pay for drawings. Call (877) 610-1318 for a straight answer.
Because the expansive clay soils common on those lots shrink and crack during the dry months, then heave when winter rains return. That cycle stresses slabs and retaining walls, and West Hollywood’s building department routinely requires a soils report for any ground-disturbing work on those hillside-adjacent lots. It’s not optional, and it’s not cheap, but skipping it is how foundations crack. We’ve built on these lots enough to know when a soils engineer is coming up before we even pull the permit.
Every allowance is in writing. Every scope is in writing. Every price change arrives as a written change order before work happens. On a shared-wall courtyard bungalow or dingbat conversion, that means party-wall notice costs, sound insulation upgrades, and any tenant-protection measures are spelled out in the contract, not discovered at the end. If it isn’t on paper, it’s a surprise waiting for a date. We don’t do surprises.
If you’re planning an addition, garage conversion, or ADU in West Hollywood, call (877) 610-1318 for a free estimate. Tom Barrett or one of his sons will answer. We’ll walk your lot, look at access, talk through the permit path, and put a real number in writing before you sign anything.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving West Hollywood since the day we pulled our first permit here.