







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable ADU Builders Across Woodland Hills
Adding an ADU in Woodland Hills means building for two things most of Los Angeles never has to think about: 110°F summers and Wildland-Urban Interface fire codes. A detached ADU here typically runs $220,000 – $390,000, and the materials you choose decide whether the unit stays livable in August and passes LADBS inspection in October. We build ADUs that hold up to both. Call (559) 249-3776 for a written price before any work starts.
Why Seedling ADU Woodland Hills Is Woodland Hills’s Preferred ADU Builders Company

Woodland Hills homeowners ask us about heat before they ask about square footage. That’s the right question. Our crews work on lots from Topanga Canyon Boulevard to Valley Circle, and we’ve walked enough 1950s ranch homes here to know what the electrical panel looks like before we open it. Ben Ortega, who leads our Woodland Hills projects, has spent years navigating LADBS Wildland-Urban Interface requirements in this specific pocket of the Valley. He knows which roofing assemblies pass inspection the first time and which ones get flagged for a re-visit that costs you three weeks.
What we hear from Woodland Hills customers over and over: the crew left the house cleaner than they found it, and the price never moved. That’s the Cedarwell Care Promise in practice. Shoe covers and drop cloths inside the home. Pet-safe products where there’s a choice. A photo of the clean-up before the crew leaves. Every project, no exceptions.
ADU Construction in Woodland Hills
ADU Construction in Woodland Hills is a different job than ADU construction in Burbank or Torrance, because the San Fernando Valley’s western edge sits in a designated Wildfire Hazard Severity Zone. That one fact rewrites your materials list before the first foundation stake goes in. A typical attached or detached ADU Builders project here runs $200,000 – $380,000 depending on size, site access, and whether the original home needs a panel and sewer lateral upgrade.
What most Woodland Hills homeowners don’t expect is how much of the budget goes underground. Homes built between 1955 and 1975 often still run original cast-iron sewer laterals and 60-amp or 100-amp panels. LADBS won’t sign off on a second dwelling until both are addressed.
Fire-Rated Assemblies Are Not Optional Here
In Woodland Hills, LADBS requires Class A fire-rated roofing and exterior materials on any new ADU. That means standing-seam metal, fiber cement siding from James Hardie, and dual-pane tempered glass. Standard asphalt shingles and wood siding will fail inspection. This is not a place to save money on the envelope.
Cooling Loads Drive the Design
Summer highs in Woodland Hills regularly cross 110°F, and a poorly insulated ADU becomes a hard-to-occupy box by early afternoon. We specify high-SEER mini-splits, radiant barriers under the roof deck, and window placement that cuts western exposure. The ADU has to work as a home in July, not just as a floor plan in a brochure.
Detached ADU in Woodland Hills

Detached ADU construction in Woodland Hills is the most common project we build here, because the lot sizes actually support it. A 500-square-foot detached studio ADU typically runs $230,000 – $320,000. A 1,000-square-foot two-bedroom detached unit runs $320,000 – $390,000. Your written price is locked before we start, and the 365-Day Done Right Promise covers the finished build.
On a flat street in Woodland Hills, a homeowner needed a detached ADU for an aging parent. We replaced the original 1960s 100-amp panel with a 200-amp solar-ready panel before framing, because their existing service would never pass LADWP inspection under the added summer cooling load. The crew then installed a high-SEER Mitsubishi mini-split and a standing-seam metal roof with a radiant barrier. That’s the only way to keep the ADU habitable when outdoor temps hit 110°F.
Panel Upgrades Come First
If your Woodland Hills home still runs a 100-amp panel, the ADU will push it past its limit. Two dwellings running air conditioning in August will trip the main breaker. LADWP requires a 200-amp service for most ADU projects here, and the upgrade runs $4,500 – $8,000 depending on whether your meter location can stay as-is.
Prefab ADUs Work Well Here
Woodland Hills lots are generally flat and accessible, which makes prefab and modular ADUs from Abodu, Cover, and Dvele a strong fit. You get factory-built precision and a shorter on-site timeline. We handle the site work, foundation, utilities, and the LADBS sign-off.
Trusted Brands We Service in Woodland Hills
We work directly with the manufacturers serious ADU buyers research before calling anyone: Abodu, Cover, and Dvele for prefab and modular builds, and James Hardie for fire-rated exterior materials. Because we run these product lines through our Woodland Hills projects regularly, we know lead times, installation quirks, and which model fits which lot shape best. You don’t get pushed into what the builder prefers to sell; you get the product that fits your lot and your budget.
Common ADU Builders Problems We See in Woodland Hills Homes
- Corroded roofing fasteners from salt-laced Santa Ana winds. Inland-rated fasteners fail within a few years out here. We specify stainless or hot-dip galvanized hardware on every exterior connection.
- Rotting fence posts and deck footings. Sprinkler overspray and high soil moisture in this part of the Valley eat untreated wood fast. We use pressure-treated or steel posts and sealed joints.
- Asphalt shingle roofs that fail Wildland-Urban Interface inspection. This is the most common surprise on Woodland Hills ADU projects. Class A assemblies are required, not optional.
- Undersized electrical panels that can’t carry two homes. The original 100-amp service from a 1960s ranch can’t handle a second dwelling’s cooling load. A 200-amp upgrade is usually mandatory before framing.
Pricing for ADU Builders in Woodland Hills, CA
A studio ADU in Woodland Hills runs $200,000 – $280,000. A one-bedroom detached unit runs $250,000 – $330,000. A two-bedroom detached ADU runs $320,000 – $390,000. Garage conversions land lower, usually $140,000 – $220,000, because the foundation and roof are already there. What moves the price: panel upgrades, sewer lateral replacement, site access for equipment, and the fire-rated exterior package. The coastal-spec materials cost 10 – 15% more than inland-grade, but the cheap spec corrodes and rots within a decade. You’ll pay the difference either way. We’d rather you pay it once, up front, in writing. Call (559) 249-3776 for a free estimate.
We Also Serve Cities Near Woodland Hills
Our crews serve Woodland Hills and the surrounding communities: Canoga Park, Topanga, Tarzana, and West Hills. If you’re just over the line in any of these areas, we’ll still bring the same written pricing and the same clean-up standard. Learn more about our work throughout ADU Builders in Woodland Hills and the wider Valley.
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 About ADU Builders in Woodland Hills
Yes, LADBS requires Class A fire-rated roofing and exterior materials on ADUs in Woodland Hills because the neighborhood sits in a Wildfire Hazard Severity Zone. Standard asphalt shingles and wood siding will fail inspection. We specify standing-seam metal, James Hardie fiber cement, and dual-pane tempered glass on every ADU we build here. Call (559) 249-3776 if you want a written estimate that includes the fire-rated package.
Because two dwellings running air conditioning in a Woodland Hills summer will trip a 100-amp main breaker. LADWP requires a 200-amp service for most ADU projects here, and the upgrade typically runs $4,500 – $8,000. Your original 1960s panel was sized for one home with one AC unit, not two. Call (559) 249-3776 for an exact price on your lot.
A high-SEER ductless mini-split, minimum SEER 20, sized for the unit’s square footage and western exposure. Woodland Hills regularly hits 110°F in July and August, so undersized cooling is a comfort failure and a tenant complaint. We typically pair the mini-split with a radiant barrier under the roof deck. Call (559) 249-3776 and we’ll walk your lot with a cooling load in mind.
Usually yes. Woodland Hills ranch lots are wide and relatively flat, which works well for detached ADUs. The two things that usually need attention first are the original sewer lateral and the electrical service. Both are common on 1950s and 1960s homes here. Call (559) 249-3776 for a free site walk and a written price.
We use stainless or hot-dip galvanized hardware on every exterior connection, because Santa Ana winds drive salt and fine dust into fasteners and corrode inland-rated products within a few years. This includes roofing clips, fence brackets, railing anchors, and paver joint edging. It’s a 10 – 15% material upgrade that saves you a full exterior re-fastening in year six or seven. Call (559) 249-3776 to talk specifics.
Whether you’re planning a detached ADU, a garage conversion, or a home addition in Woodland Hills, you deserve a written price before any work starts and a crew that treats your home like it’s occupied, because it is. Call (559) 249-3776 to schedule your free estimate. The phone is answered by a live person, any hour, every day.
Written by Ben Ortega, Owner at Seedling ADU Woodland Hills, building and backing ADUs in Woodland Hills under the Cedarwell Care Promise.




