Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Woodland Hills
Adding square footage in Woodland Hills means navigating a maze most neighboring cities never face. You’re not just adding a room or building a granny flat. You’re dealing with Very High Fire Hazard Severity Zone codes, hillside soils reports, and a building department that expects Chapter 7A ignition-resistant details on nearly every new wall you open up. A typical Home Additions & ADU project here runs $45,000 to $130,000, and the gap between a smooth build and a stopped job usually comes down to whether your contractor knew Woodland Hills code before the first permit was filed. We do. Call (877) 610-1318 for a free estimate, and you’ll talk to someone who knows this valley.
Why Barrett & Sons Construction Is Woodland Hills’s Preferred Home Additions & ADU Company
Tom Barrett started this company in 1998, and the name still means something in Woodland Hills. His sons run crews here, not strangers dispatched from a call center. When you walk a job site on Mulholland Drive or up near Victory Boulevard, there’s a decent chance the person answering your question is a Barrett.
What that buys you in Woodland Hills specifically is a contractor who already knows what the LA Building & Safety counter on Van Nuys Boulevard will ask for. We’ve pulled permits for hillside additions where the city rejected another contractor’s plans because there was no licensed geotechnical soils report. We’ve worked through the Chapter 7A requirements on homes up in the 91364 ZIP and ranch-style tracts down in 91367. We know which inspectors work this area and what they flag. That’s not marketing. That’s just showing up for 29 years and remembering what happened on the last job.
Every quote we give you in Woodland Hills is a written scope with line-item allowances. Every change is a written change order before work proceeds. And every job carries our 90-Day Done Right Promise, written on the contract. If something isn’t right, Tom comes back. One call.
Our Home Additions & ADU Services in Woodland Hills
ADU Design & Permitting
Woodland Hills is one of the few LA neighborhoods where a backyard ADU triggers fire hazard zoning review alongside everything else. We handle the full design package, from measured as-builts to construction documents, and we walk the permit set through the city. ADU construction in Woodland Hills typically runs $90,000 to $220,000 depending on whether you’re doing a detached unit or converting existing space, and our design work is structured so you know that number before you pay for a full plan set.

Garage Conversion ADU
Those 1950s and 1960s garages off streets like Burbank Boulevard and Shoup Avenue were never built to current fire code. Converting one into a legal ADU in Woodland Hills usually means reframing at least one wall assembly for ignition resistance, upgrading eave details, and often replacing the garage slab for drainage and insulation. Garage conversions here run $30,000 to $80,000. We’ve done enough of them to bid that work accurately the first time.

New Detached ADU
Building a new detached ADU on a Woodland Hills lot means starting from the dirt up, and on hillside parcels that can mean caissons or a grade beam foundation depending on what the soils report says. Flat valley lots are simpler but still need ember-resistant vents, dual-pane windows, and Class A roofing to clear the fire authority. We bring the geotech, the structural engineer, and the crew under one roof, so you’re not calling three different companies.

Junior ADU & Interior Conversion
A junior ADU is the fastest legal path to extra living space in Woodland Hills, especially in the 91365 and 91371 neighborhoods where lot sizes are tighter. We convert an existing bedroom or bonus room into a self-contained unit with its own entrance, kitchenette, and efficiency bathroom. Interior conversions like this run $25,000 to $80,000 depending on plumbing access and whether the existing walls meet current fire separation rules, which they often don’t in this housing stock.

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 Woodland Hills
We don’t install mystery materials off the back of a van. On Woodland Hills additions and ADUs, we specify Andersen windows for dual-pane fire-rated assemblies, CertainTeed roofing when a new structure calls for Class A, and Belgard or Techo-Bloc when the project includes a hardscape connection or drainage swale. These are brands you can look up, with published specs that satisfy the fire marshal and the building inspector. We order direct and stock the common trim and flashing parts for faster turnaround on Woodland Hills jobs, because running to a supply house in Canoga Park mid-project costs you time.
Common Home Additions & ADU Problems We See in Woodland Hills Homes
- Open eave soffits on 1950s and 1960s ranch homes. The original construction predates every modern wildfire code. The moment we pull a permit for a room addition, the city typically requires those eaves to be boxed in or replaced with ignition-resistant material, which changes the project budget and scope. We plan for that from the first site visit, not after the inspector circles it in red.
- Hillside lots with expansive clay soil. Streets climbing toward Mulholland Drive sit on soil that swells and shrinks with our extreme heat and winter rain. Building an addition or detached ADU on that ground without a geotechnical report is a fast way to get a permit rejected and a foundation that cracks.
- Extreme heat stress on framing and finishes. Woodland Hills regularly posts the highest temperatures in LA County. Framing lumber and stucco move more here than they do in Santa Monica. We detail joints, flashing, and expansion gaps for that reality, because standard coastal details don’t hold up over a run of 100-degree days.
- City-required fire hardening on any substantial remodel. Open up a wall on a Woodland Hills home and the building department will likely require ember-resistant vents, dual-pane windows, or a Class A roof before they’ll sign off on the addition. A contractor working Sherman Oaks might never mention it. We mention it at the estimate, because it’s coming.
Pricing for Home Additions & ADU in Woodland Hills, CA
Here’s straight talk on numbers. A room addition in Woodland Hills runs $45,000 to $130,000. A new detached ADU runs $90,000 to $220,000. A garage conversion runs $30,000 to $80,000. What moves the number most is whether you’re on flat valley floor or a hillside lot that needs caissons, and how much fire-hardening retrofit the city triggers on the existing structure. We give you a written line-item scope before you sign anything, and every allowance is on paper. If the city adds a requirement mid-project, you get a written change order with the new number before we order materials. No surprise invoices at the end, because as Tom says, the allowance that isn’t on paper is a surprise waiting for a date. Call (877) 610-1318 for an exact quote on your Woodland Hills project, free.
We Also Serve Cities Near Woodland Hills
Our crews work throughout the west valley, so if you’re a few minutes out in Woodland Hills or over in Canoga Park, Calabasas, West Hills, or Topanga, we can schedule the same free estimate. The same crew that handles your addition in Woodland Hills will often run the Kitchen Remodeling in Woodland Hills or Bathroom Remodeling in Woodland Hills job you’ve been putting off, too. One contractor, one point of contact.
Serving Woodland Hills, CA - Our Local Coverage Area
We’re based in the Woodland Hills 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 Woodland Hills
We typically begin the design and permitting phase within one to two weeks of your signed agreement, and site work follows once the city approves the permit set. That timeline is longer in Woodland Hills than in unincorporated county pockets, because fire authority review and the hillside soils requirement add steps. We’ll give you a written schedule at the estimate, and we answer our own phone, so you’re never calling a call center to ask where things stand. Call (877) 610-1318 to talk to a live person about your timeline.
Yes. We cover 91364, 91365, 91367, and 91371, from the valley floor up through the hillside streets toward Mulholland Drive. Each area has its own code triggers, and we’ve worked enough of this city to know which ones apply before we write your estimate.
Generally yes, and it’s because of the fire hazard zone requirements. Chapter 7A materials and assemblies add real cost, and hillside lots add foundation and soils engineering work. An ADU that runs $90,000 in parts of Canoga Park will often land closer to $150,000 or more on a steep Woodland Hills lot when caissons come into play. We’ll show you exactly where the money goes in your written scope.
It covers the full scope of work on your contract. If anything we built isn’t functioning the way it should within 90 days of completion, Tom Barrett comes back and makes it right. One call to the number you’ll already have, and the guy whose name is on the truck returns to your Woodland Hills home. It’s written on every contract, not buried in fine print.
We pull permits and sign off on inspections for every eligible job. You won’t be asked to meet the inspector, and you won’t be told permits are optional. The permit inspector works for you, not for me. Tom likes it that way, and so do the homeowners we’ve worked with up and down this valley.
Ready to get a real number for your Woodland Hills addition or ADU? Call (877) 610-1318 today. We’ll set up a free estimate, walk your lot, and give you a written scope with real numbers, not a ballpark. No pressure, no surprises, just straight answers from a contractor who’s been doing this since 1998.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Woodland Hills and the west valley since 1998.







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