A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Santa Monica, CA
Adding an ADU or home addition in Santa Monica means working with a city that has its own building culture: tight lots, strict coastal zoning rules, and a housing stock that ranges from 1920s Spanish colonials to mid-century bungalows. Sutton ADU Builders handles all three of our Santa Monica services – detached ADUs, home additions, and room additions – with a written price before any tool is lifted. The coastal climate is forgiving, but the permit process isn’t, and we’ll walk you through it. Call (472) 248-8213 when you’re ready to talk numbers.
Why Santa Monica Homes Are Different
Santa Monica’s housing stock skews older and denser than most of Los Angeles County. Many lots in the Wilshire-Montana and Sunset Park neighborhoods sit at 5,000 to 7,500 square feet, which means setbacks (the required gap between your new structure and the property line) often dictate whether a detached ADU even fits. We regularly see 1920s and 1930s homes with pier-and-beam foundations that need seismic anchoring before an addition can be permitted. The coastal marine layer keeps framing lumber from drying out too fast, but it also means exterior paint and siding specs have to account for salt air and fog. Homes in the Ocean Park and Pico districts often sit on alleys, which changes how we stage materials and where a crane can go for a prefab ADU delivery. The city’s zoning rules treat single-family lots and multi-family properties differently, and some HOAs in the northern neighborhoods layer their own review on top of city permits. None of this should surprise you mid-project – it should be in the written scope from day one.
Our Main Santa Monica Services
The two jobs Santa Monica homeowners call us about most are garage conversions and detached ADUs, with room additions close behind. Each has its own page with pricing, timelines, and local specifics.
Home Addition Contractor in Santa Monica
A home addition in Santa Monica usually means expanding the main house rather than building a separate structure. Common projects include second-story additions on Sunset Park bungalows and rear expansions off Ocean Park kitchens. The local catch is foundation work: many older Santa Monica homes need seismic retrofitting before the addition can tie in. Our crews handle the structural scope and the finish work. Miles Hartwell leads each estimate personally so the written price reflects what the job actually needs. Home Addition Contractor in Santa Monica.
ADU Builders in Santa Monica
Detached ADUs are the most permit-heavy project we do in Santa Monica. The city allows ADUs on most single-family lots, but side and rear setbacks, height limits, and parking replacement rules all shape the design. We’ve built with prefab lines like Abodu and Dvele where the lot access makes sense, and stick-framed when the site demands custom. Every ADU starts with a site visit and a written price, not a vague estimate. ADU Builders in Santa Monica.
Room Addition Contractor in Santa Monica
A room addition in Santa Monica is the most targeted way to add square footage: one new bedroom, a family room off the back, or an office above the garage. These jobs usually move faster than full ADUs because the scope is tighter. The main Santa Monica variable is foundation type – some homes can support a simple slab-on-grade addition, others need drilled piers. We’ll tell you which one your lot requires before you commit. Room Addition Contractor in Santa Monica.
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 Santa Monica
We work with prefab and modular ADU lines including Abodu, Dvele, and Cover, plus James Hardie exterior systems for siding and cladding. Our crews are experienced with their anchoring and finish requirements, which keeps inspections moving. See our brands for the full list.
Pricing for ADU Company in Santa Monica, CA
| Service | Typical range in Santa Monica |
|---|---|
| Detached ADU (400 – 600 sq ft) | $180,000 – $320,000 |
| Detached ADU (600 – 800 sq ft) | $250,000 – $400,000 |
| Garage conversion to ADU | $120,000 – $220,000 |
| Prefab ADU (Abodu, Dvele, Cover) | $160,000 – $300,000 |
| Home addition (single room) | $80,000 – $150,000 |
| Second-story addition | $200,000 – $400,000 |
| Room addition (foundation-to-roof) | $70,000 – $140,000 |
| Kitchen addition | $90,000 – $180,000 |
Santa Monica add-ons hit the higher end of these ranges when the lot is tight, the foundation needs seismic work, or alley access limits crane use for a prefab drop. The price we give you is written and fixed before work starts – no change orders slipped in later. That’s the Threshold Standard, and it applies to every project in Santa Monica.
Neighborhoods We Serve in Santa Monica
Sutton ADU Builders covers all of Santa Monica, from the beach-adjacent blocks to the eastern edge near the 405. Most of our estimates happen within a few business days of your call.
- Sunset Park
- Ocean Park
- Wilshire-Montana
- Pico District
- North of Montana
Service Area – Cities Near Santa Monica
We also serve homeowners just outside Santa Monica, including Venice, CA, Pacific Palisades, CA, Marina del Rey, CA, and Culver City, CA. Each city has its own building department and inspection quirks, but the pricing promise and the 365-Day Done Right Promise travel with us.
Serving Santa Monica, CA - Our Local Coverage Area
We’re based in the Santa Monica 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 Santa Monica
Most site visits in Santa Monica are scheduled within three to five business days of your call. The visit is free and includes a written price afterward, so you’re not left guessing while the city’s permit clock runs. Call (472) 248-8213 to book.
Yes. We prepare and submit city permit packages for every project and work with your HOA’s architectural review board when one applies. The permit timeline in Santa Monica varies, but we’ll map it out clearly before work begins.
Yes – everyone who arrives at your property is background-checked, identity-verified, and photo-badged under the Threshold Verified standard. You’ll receive the name and photo of each technician before they arrive, every time. Call (472) 248-8213 for a free estimate.
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 Santa Monica Customers Say
"Every crew member was vetted and carried a badge, which matters when they are around your family for months. Tidy site every day."
- Daniel F."Itemized estimate with allowances laid out. Final cost was within a hair of the quote."
- Naomi R."Backyard ADU for my mother. The project manager showed ID and walked me through the permit steps, the foundation plan, and the schedule. Moved her in on time."
- Margaret C.
