







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Malibu, CA
Benson ADU Builders handles ADU construction, home additions, and room additions across Malibu, CA. Most Malibu jobs share a few realities: older hillside homes on compact lots, strict coastal and wildfire-zone building codes, and neighborhoods where every square foot of flat ground counts. We write the price down before anything starts, then hold to it. Call (903) 568-7222 for a free estimate on your Malibu project.
Why Malibu Homes Are Different

Malibu isn’t one housing market. Point Dume and the Malibu Colony have coastal aging stock from the 1960s and 70s that predates modern setback rules. The hills above Pacific Coast Highway, including Big Rock, Las Flores Canyon, and the Serra Retreat area, bring steep grades, tricky utility runs, and fire-zone defensible-space requirements that change where an ADU can sit on the lot. A flat lot in central Malibu near the Civic Center might clear planning review quickly, while the same 800-square-foot footprint on a hillside above Zuma needs geotech sign-off and likely a foundation engineered for lateral movement.
That terrain split is the single biggest factor in Malibu pricing. Hillside work runs higher on excavation, retaining, and access. Coastal-flat lots run higher on corrosion-resistant hardware and salt-air material choices. We see both every month, and we price them differently because they are different jobs. What Malibu homeowners rarely realize: the accessory dwelling unit rules here are actually more flexible than most of Los Angeles County. Senate Bill 9 and state ADU mandates override many local height and setback limits, which means a detached ADU over a garage on a Point Dume lot that looked impossible in 2019 is often buildable now.
Our Main Malibu Services
Three services carry most of our workload in Malibu. Here’s what each one actually involves on the ground here.
ADU Builders in Malibu
An ADU in Malibu, CA means either a detached unit in the yard, a garage conversion, or a JADU carved out of the existing house. JADU stands for junior accessory dwelling unit, and it’s the fastest path: a bedroom-to-kitchenette conversion under 500 square feet, often with no added parking requirement. We build with Abodu, Dvele, and Boxabl prefab systems where the lot can take a panelized build, which cuts weeks off a Malibu hillside schedule because panels arrive pre-cut and crane into place. Read the full scope on our ADU Builders in Malibu page.

Home Addition Contractor in Malibu
A Malibu home addition usually means pushing out on an existing slab or up over a garage. Most of the work we quote here is coastal-flat or mid-hills, and the question that drives the price is foundation type. A standard slab-on-grade addition off a kitchen in central Malibu is straightforward. A second-story bump on a 1970s frame above Las Flores Canyon needs structural review before we’ll even put a number on it. That’s not a stall tactic; it’s how you avoid the $40,000 surprise later. Full breakdown is on Home Addition Contractor in Malibu.

Room Addition Contractor in Malibu
A room addition in Malibu is the tightest scope of the three: single bedroom, home office, or bath expansion. The catch here is that even a 200-square-foot bump on a 1960s beach house can trigger an electrical service upgrade or seismic retrofit requirement under current code, which is why our written quotes always include the permit path and any service-panel work up front. No “we’ll figure it out after demo.” Detail on Room Addition Contractor in Malibu.

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 Malibu
We build with James Hardie cladding for coastal weather resistance, and Abodu, Cover, and Dvele prefab systems where panelized construction saves time and waste on a tight Malibu lot. Parts for these systems are stocked through our Los Angeles distribution network. See what we work with on our brands page.
Pricing for ADU Company in Malibu, CA
| Service | Typical range in Malibu |
|---|---|
| Detached ADU (site-built) | $180,000 – $350,000 |
| Detached ADU (prefab: Abodu, Dvele, Boxabl) | $150,000 – $280,000 |
| Garage conversion ADU | $90,000 – $180,000 |
| JADU (junior ADU, under 500 sq ft) | $50,000 – $110,000 |
| Home addition (ground-floor, slab) | $180,000 – $400,000 |
| Home addition (second-story bump) | $250,000 – $550,000 |
| Room addition (single room) | $60,000 – $140,000 |
| Room addition (primary suite with bath) | $110,000 – $220,000 |
Steep grades and wildfire-zone requirements push Malibu pricing toward the top of these ranges, especially on hillside lots where excavation and retaining walls enter the quote. Flat coastal lots with simple utility access tend to land mid-range. Whatever the number, it’s the number: we give every Malibu homeowner a written price before work starts, and that’s the backstop on the whole project.
Neighborhoods We Serve in Malibu
We work the full stretch of Malibu, CA, from the Ventura County line to Topanga, including the hillside canyons and every beachside pocket between. Typical scheduling for a Malibu estimate runs within a few business days.
- Point Dume
- Big Rock
- Las Flores Canyon
- Serra Retreat
- Central Malibu / Civic Center
Service Area – Cities Near Malibu
Benson ADU Builders also covers the neighboring communities Malibu homeowners regularly ask about. If your property sits just east or north of the city line, we serve Agoura Hills, CA, Westlake Village, CA, Thousand Oaks, CA, and Calabasas, CA with the same written-price commitment.
Serving Malibu, CA - Our Local Coverage Area
We’re based in the Malibu 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 Malibu

Most ADUs in Malibu do not require a separate Coastal Commission permit if the lot is in the coastal zone but the unit meets state ADU law. If your property is west of Pacific Coast Highway or on a bluff, the Coastal Act still applies, and we’ll flag that during the estimate. Call (903) 568-7222 to talk it through.
Plan on 6 to 10 months for a site-built detached unit, and 4 to 6 months for a prefab build like Abodu or Dvele where the panels arrive pre-assembled. Hillside access and utility trenching add time. We’ll give you a written schedule with the price.
Yes. Wildfire-area rules mean Class A roofing, ember-resistant vents, and specific vegetation clearance distances in most Malibu, CA hillside neighborhoods. Those requirements go into the quote from day one, not as a change order after plans are drawn. Call (903) 568-7222 for specifics on your lot.
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 Malibu Customers Say
"Booked a consult online and met the project manager two days later. Weekly progress updates arrived by text with photos. ADU finished on schedule."
- Hannah W."Clean, quiet crew. They respected the neighbors, kept noise to working hours, and swept the driveway every evening."
- Hope C."Communication was the best part. I always knew what was happening that week without having to ask."
- Dolly N.



