ADU Company in Castaic, CA
Lodgewick ADU Builders handles accessory dwelling units, garage conversions, and home additions in Castaic, CA, and this page is the starting point for every job we take on here. The homes we work on in Castaic are mostly 1970s to 1990s tract builds on generous lots that can hold a detached ADU, but the grading, retaining, and fire-zone code layers make these jobs different from anything in neighboring Santa Clarita. If you’re pricing an ADU in Castaic, call (254) 602-5618 and we’ll give you a written number before any work starts.
Why Castaic Homes Are Different
Castaic is unincorporated Los Angeles County, which means every ADU permit runs through LA County Building and Safety rather than a city building department. That changes the fee schedule, the plan-check cadence, and the inspection process compared to what a contractor working mostly in Santa Clarita or City of LA is used to. We know that process and we prepare for it from the first site visit.
More than that, large portions of Castaic sit in High or Very High Fire Hazard Severity Zones. A detached ADU here isn’t a simple rectangular build. CALGreen Chapter 7A applies, which means ember-resistant vents, ignition-resistant exterior materials, and defensible-space requirements written into the plans. The Santa Ana winds that funnel through the I-5 corridor make wind-driven ember intrusion a real design constraint on roof, vent, and eave detailing. Homes closer to Castaic Lake and the canyon roads add another wrinkle: many older parcels are still on private septic systems, and a new ADU legally requires a percolation re-evaluation and often a system upgrade or second leach field. We raise that cost early, because finding it out at rough-in is a budget-killer.
The housing stock helps. Many Castaic lots have side yards or rear slopes that physically fit a detached ADU footprint. What they need is grading and retaining work, and we plan for that in the written price rather than discovering it mid-build.
Our Main Castaic Services
These are the three jobs Castaic homeowners call us about most often. Each one has its own Castaic page with full pricing, local conditions, and timelines.
Home Addition Contractor in Castaic
A home addition in Castaic means squaring the new roofline with an existing 1970s or 1980s frame, and that starts with an honest look at what the original structure can carry. We see a lot of rear and side-yard additions on Castaic lots that work, but the hillside grading near the canyon edges changes the foundation plan. Our Home Addition Contractor in Castaic page walks through what a build like this costs and what the county will ask for before we pour.
Garage Conversion Contractor in Castaic
Garage conversions make sense in Castaic because the existing slab and roof line are already permitted, which trims cost and cuts plan-check time. The catch is that many 1980s Castaic garages were never insulated or fire-rated to living-space standard, and a conversion triggers the same fire-zone exterior requirements if we touch the shell. Our Garage Conversion Contractor in Castaic page details what gets upgraded and what that costs.
ADU Builders in Castaic
Detached ADUs in Castaic are the most code-intensive build on this list. Fire-hardened exteriors, ember-resistant venting, defensible space, possibly a septic upgrade: every one of those items is a line in a written quote, not a surprise change order. We work with prefab ADU manufacturers like Boxabl and Dvele where they fit a Castaic lot, and we handle stick-built where they don’t. Our ADU Builders in Castaic page breaks down the full build.
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.
Brands We Service in Castaic
We service and build with ADU systems from our brands, including Boxabl, Dvele, and Mighty Buildings. Parts and materials for these systems are stocked in our Los Angeles-area warehouse, so Castaic projects don’t stall waiting on a delivery from out of state.
Pricing for ADU Company in Castaic, CA
| Service | Typical range in Castaic |
|---|---|
| Detached ADU (stick-built, full build) | $180,000 – $350,000 |
| Detached ADU (prefab, including Boxabl or Dvele) | $140,000 – $280,000 |
| Garage conversion to ADU | $90,000 – $180,000 |
| JADU (attached junior ADU, permits included) | $65,000 – $120,000 |
| Home addition (200-400 sq ft, attached) | $60,000 – $140,000 |
| Home addition (400-800 sq ft, attached) | $120,000 – $240,000 |
| Septic percolation re-evaluation + system upgrade | $8,000 – $35,000 |
| Fire-zone exterior hardening (CALGreen 7A compliance) | $6,000 – $22,000 |
| Grading and retaining wall (hillside lots) | $15,000 – $60,000 |
| Plan set and county permit package (LACBS) | $4,000 – $12,000 |
What pushes a Castaic price up, more than anything, is fire-zone hardening and septic work on the older canyon-side parcels. What keeps it predictable is our pricing: the written quote you get before we start is the price you pay, no change orders at the door.
Neighborhoods We Serve in Castaic
We work across Castaic, from the newer subdivisions near the I-5 to the older parcels along Castaic Lake and the canyon roads. Same crew standards, same written price, same guarantee in every part of town.
- Castaic Lake area and canyon roads
- Northlake
- Val Verde
- Hasley Canyon
- Hillgate / Sloan Canyon
For most Castaic jobs, our scheduling team confirms a written arrival window within one business day of your call.
Service Area – Cities Near Castaic
The Lodgewick ADU Builders team serving Castaic also covers Valencia, CA, Stevenson Ranch, CA, Santa Clarita, CA, and Newhall, CA. Dispatch and scheduling are coordinated from our Los Angeles office; crews serve Castaic locally.
Serving Castaic, CA - Our Local Coverage Area
We’re based in the Castaic 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 Company in Castaic
Most Castaic projects move from signed agreement to county submittal within three to four weeks, with site work starting after LACBS plan check clears. Prefab builds move faster. Call (254) 602-5618 for a current timeline on your specific lot.
Only if your parcel is on a private septic system, which is common on older lots near Castaic Lake and the canyon roads. We order the percolation re-evaluation early in the process, so you know the real number before you commit to the build.
No. Our written price is the price, and that’s the point of the Kingswell Guarantee. If something is found during site work that we should have caught in the quote, that’s on us. Call (254) 602-5618 and we’ll put the number in writing before anything is signed.
For a free estimate on an ADU, garage conversion, or home addition in Castaic, call Lodgewick ADU Builders at (254) 602-5618. A live person answers, and the price you get is the price you’ll pay.
What happens when you call
- 1A real person answersNo phone trees - talk to a local adu pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3We come out and measureLicensed & insured, at a time that suits you - the visit and the quote are both free.
- 4You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.
What Castaic Customers Say
"A whole backyard ADU from scratch. Terrified me going in, but they kept me updated weekly and there were no nasty surprises. Quality work and a fair price."
- Noreen Fletcher"Built a backyard unit for my mother in law. They handled the permits, gave me a real timeline, and stuck to it within a few days. The written price is what we paid, which anyone who's done construction knows is rare."
- Dennis Fairchild"Garage conversion into a studio for our teenager. Honest about what was realistic and what wasn't, finished close to schedule, and cleaned up the site daily."
- Marcus Beaumont