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 Hollywood
A home addition in Hollywood typically runs $45,000-$130,000, while a full detached ADU from design through sign-off lands between $90,000 and $220,000. Those are the honest numbers for this market, shaped by hillside grading rules and historic district review that flatland contractors never see coming. If you own property in the 90028 ZIP or the surrounding blocks, you need a crew that already knows how Hollywood’s building department thinks. Call (877) 610-1318 and we’ll walk your lot with you before you spend a dime.
Why Barrett & Sons Construction Is Hollywood’s Preferred Home Additions & ADU Company
We’re Tom Barrett’s company, founded in 1998, and my sons run the crews you’ll see on your job. That matters in Hollywood more than most places, because this is a neighborhood where an out-of-area contractor can lose three weeks just figuring out which review board wants what. We’ve pulled permits for additions on streets running up into the Hollywood Hills and on flatland lots off Santa Monica Blvd, so we don’t show up surprised when the Office of Historic Resources asks for elevation drawings on a bungalow addition.
Customers here don’t hand over a five-figure ADU budget to a call center. They want a name they can check. Tom Barrett publishes his name, his address, and his license number, and a live person answers our phone 24 hours a day, every day. Background-checked crew members wear the Barrett & Sons name on their shirts and the permit inspector’s name goes on your paperwork, not just ours.
Our reputation in Hollywood is built on written change orders before any scope moves and the 90-Day Done Right Promise on every contract. One call brings Tom back. That promise has kept us busy in this ZIP since before most of the current soft-story retrofit deadlines hit.
Our Home Additions & ADU Services in Hollywood
ADU Design & Permitting
An ADU in Hollywood starts with two questions: is your lot in a Historic Preservation Overlay Zone, and is your existing structure on the City’s soft-story retrofit list. We’ve navigated both for properties throughout the 90028 ZIP and the surrounding blocks. Our in-house design work covers the full permit package, including hillside grading plans when your lot climbs toward the Santa Monica Mountains, and we walk it through the City of Los Angeles plan check ourselves. You’ll see every allowance in writing before construction starts, because an allowance that isn’t on paper is a surprise waiting for a date.
Garage Conversion ADU
Hollywood’s tuck-under parking garages from the 1950s through the 1970s create a specific challenge here. Many of those wood-frame buildings are now subject to mandatory soft-story retrofit work under Ordinance 183893, which means a garage conversion ADU has to be engineered alongside or after the required seismic upgrades, not as a separate cosmetic job. We coordinate both scopes so you’re not tearing out new drywall to install a moment frame later. Garage conversions in Hollywood run $30,000-$80,000 depending on foundation and retrofit conditions, and we give you that range in writing before the first hammer swing.
New Detached ADU
A new freestanding ADU on a Hollywood flatland lot is a cleaner build than a conversion, but hillside parcels up toward the canyons bring steep-slope grading permits and drainage requirements that require engineers who know this terrain. We’ve built detached units behind Craftsman bungalows and Spanish Colonial courtyards, and we spec materials that clear the HPOZ design review without a fight. Budget $90,000-$220,000 for a complete new detached ADU in this market, including utilities, foundations, and final inspection sign-off.
Junior ADU & Interior Conversion
A Junior ADU carved out of an existing Hollywood home is often the fastest path to rental income, but the older housing stock here adds a wrinkle. Many 1920s and 1930s interiors still carry knob-and-tube wiring and wood-lath plaster, which must be addressed before an interior conversion passes inspection. We handle that remediation as part of the JADU scope rather than leaving it as a surprise line item at the end. Our written change order process means if we find something behind the plaster, you see the number on paper before work proceeds.
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 Hollywood
We stock and install Simonton, Ply Gem, and PGT windows and doors for Hollywood when additions and ADUs call for new openings or replacements, and we keep turnaround tight for Hollywood projects because the building department here has enough paperwork without us adding parts delays. These are brands you can look up, with published performance ratings and warranties, not mystery products pulled off a van. When your Hillside addition needs windows engineered for wind and seismic load, we spec them correctly the first time.
Common Home Additions & ADU Problems We See in Hollywood Homes
- Historic district sign-off delays: Courtyard bungalow complexes in Hollywood’s HPOZ districts require sign-off from the LA Office of Historic Resources before a re-roofing or stucco-repair permit is issued on what looks like routine exterior work. Out-of-area contractors lose weeks here; we file those reviews as step one, not step ten.
- Soft-story retrofit conflicts: The dense concentration of 1960s-70s wood-frame apartments with tuck-under parking across Hollywood’s flatland corridors falls under the City’s mandatory seismic retrofit ordinance, which means an addition or ADU on those lots must be engineered around or alongside required structural steel work. We sequence both scopes so the ADU doesn’t get torn open later.
- Hillside grading and drainage: Properties pushing up into the Santa Monica Mountains carry steep-slope grading permits, expansive hillside soils, and post-wildfire erosion control requirements that flatland LA contractors rarely handle. We bring engineers who work hillside lots in Hollywood specifically, so your foundation plan passes the first review.
- Aging electrical and plaster systems: The early-20th-century housing stock that gives Hollywood its character also means knob-and-tube wiring and wood-lath walls hiding behind beautiful old stucco. Every addition here needs a realistic electrical and structural assessment up front, which is exactly what our written scope provides before pricing is finalized.
Pricing for Home Additions & ADU in Hollywood, CA
Here are the ranges to plan against for this market. A room addition in Hollywood runs $45,000-$130,000 depending on square footage, foundation work, and whether you’re on a flatland lot or a hillside parcel requiring grading. A detached ADU runs $90,000-$220,000 all in. A garage conversion lands between $30,000 and $80,000, but soft-story retrofit coordination can shift that number, which is why we give written allowances before starting. A Junior ADU or interior conversion typically falls in the $45,000-$90,000 range once electrical remediation and egress work are included. Permits, inspections, and engineering all sit inside the written change order process, so the number you approve is the number you pay. Call (877) 610-1318 for a free estimate and a written line-item quote on your specific Hollywood lot.
We Also Serve Cities Near Hollywood
Our crews cover Hollywood and the surrounding communities of Universal City, West Hollywood, Koreatown, and Echo Park. If you’re a few blocks outside the 90028 ZIP or just over the border, we’re already working nearby. For the full picture on our process and pricing, visit our Home Additions & ADU hub page or see how a kitchen scope fits alongside an addition through our Kitchen Remodeling in Hollywood service. We also pair additions with Bathroom Remodeling in Hollywood when homeowners want the whole floor plan done at once. And every one of these jobs across Hollywood carries the same written change orders and 90-Day Done Right Promise.
Serving Hollywood, CA - Our Local Coverage Area
We’re based in the 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 Hollywood
After the written estimate is approved, plan check and HPOZ review are the real clock, not our crew schedule. A flatland addition outside a historic district can often start within a few weeks of permit issuance; an HPOZ property or hillside lot adds review time we’ll map out for you at the first site visit. Call (877) 610-1318 to get your specific timeline, and we’ll put it on paper.
Yes, we work the entire 90028 ZIP and the surrounding Hollywood area, from flatland corridors off Santa Monica Blvd up into the hillside streets. Hillside lots need different engineering and drainage plans, which our Hollywood roofing and construction crews handle as standard scope, not as an upsell. Call for a free site walk and we’ll tell you exactly what your parcel requires.
Hollywood additions run $45,000-$130,000, which sits slightly above West Hollywood and Koreatown averages because of the HPOZ review step and the prevalence of hillside parcels. The historic district sign-off alone can add weeks of review time that out-of-area contractors don’t plan for. We build that into the schedule and price from day one, which is why our quotes don’t balloon mid-job.
Only if you change the scope, and even then the new number comes to you as a written change order before anyone picks up a tool. Tom Barrett’s rule is that every allowance, every material selection, and every change gets put on paper first. We don’t hand you a different bill at the end, which is the exact reason Hollywood homeowners keep calling us back. Call (877) 610-1318 if you have a written estimate from another contractor and want our second opinion on it, free.
Yes, we pull every eligible permit and manage the HPOZ and Office of Historic Resources review process ourselves, including elevation drawings for anything that touches an exterior on protected properties. The permit inspector works for you, not for us, and we want that inspection signed before final payment. Our 90-Day Done Right Promise backs the finished work, and it’s written on every Hollywood contract.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Hollywood since 1998.