Fast, Reliable Home Addition Contractor Across Santa Monica
Room additions in Santa Monica typically run $220 – $430 per square foot for a standard build-out, and most projects we quote land between $95,000 and $240,000 depending on foundation work, coastal review requirements, and finish level. That’s the honest range, and it’s higher than inland because of what Santa Monica’s housing stock and coastal rules actually demand. We work here every week, so we know what a 1940s bungalow on a 50×150 lot off Pico or Wilshire turns up once the walls are open. If you’re planning a home addition anywhere in Santa Monica, call (254) 602-5618 and we’ll put a written price in front of you before any work starts.
Why Lodgewick ADU Builders Is Santa Monica’s Preferred Home Addition Contractor Company
Lodgewick ADU Builders is the ADU company of the Kingswell family, founded in 2010, and our Home Addition Contractor team has spent years working inside Santa Monica’s older homes. We know what’s behind the lath-and-plaster walls of a Sunset Park craftsman, what the salt air does to flashing on a North of Montana bungalow, and what the Coastal Zone rules mean for a second-story addition near Ocean Park. That local knowledge means we don’t get surprised mid-project, and neither do you.
Every job we take in Santa Monica operates under The Kingswell Guarantee. A written price before work begins. A defined arrival window. A clean job site. A written guarantee on every project, with a free return visit if the work fails within the 365-Day Done Right Promise period. Russ Delmar, who leads our Santa Monica projects, reviews every estimate personally before it reaches your hand. Calls are answered by a live person, 24/7. No voicemail loops, no chatbots.
Our customers in Mid-City, Pico, and Sunset Park tell us the same thing: they’d been burned before by a contractor who quoted low and then “discovered” problems after demo. That’s why we inspect first, allowance for what we can see, and price every surprise in writing before we touch it.
Bathroom Addition Contractor in Santa Monica
A Bathroom Addition Contractor in Santa Monica has to contend with things contractors in Culver City never see: coastal humidity that rots framing behind old shower pans, 1940s plumbing stacks that no longer meet code, and tight R1 lot-coverage limits that push additions into awkward corners. We’re quoting $45,000 – $85,000 for most full bathroom additions in Santa Monica, with the higher end reflecting foundation work or a full re-pipe on pre-1960 plumbing.
What Opening the Walls Usually Reveals
Homes built before 1960 in Santa Monica frequently have cast-iron drain lines that are rusted thin at the hubs, and old shower pans with lead or failed vinyl liners that have been quietly leaking into the subfloor. Our crew documents the condition before demo starts, prices the replacement in writing, and gets your sign-off before cutting. No change orders dropped on you after the fact.
Permit Triggers and Coastal Review
Adding a bathroom doesn’t remove you from the Local Coastal Program if your parcel sits in the Coastal Zone. We check lot coverage and zoning first, because a bathroom bump-out that pushes you past R1 coverage limits can stall in coastal development review. We handle that paperwork for you, and we tell you upfront what it adds to the timeline and the price.
Bedroom Addition Contractor in Santa Monica
As a Bedroom Addition Contractor working in Santa Monica, we’re usually opening up homes where the addition means going up, not out. That’s because a detached footprint addition on a compact 50×150 lot often exceeds R1 lot-coverage limits, forcing a pivot to a second-story addition over an existing garage or rear wing. A bedroom addition in Santa Monica runs $80,000 – $160,000 in our experience, with second-story work at the upper end due to structural upgrades, stair access, and coastal massing review.
Second-Story Additions Over Detached Garages
Santa Monica has thousands of detached single-car garages built to 1940s standards: slab on grade, no stem wall, minimal seismic anchoring. Adding a bedroom above one means the garage foundation almost always needs reinforcing. We inspect for stem walls and anchor bolts early, price the upgrade in the original contract, and don’t let it become a mid-project surprise.
Sleeping Rooms and Egress
Any bedroom addition must meet egress requirements: a window large enough to escape through, a smoke alarm on the circuit, and proper ceiling height. On older Santa Monica homes, ceiling height in converted attic or garage-top spaces is the most common code failure. We measure and tell you in the estimate whether your space will pass or what it costs to fix.
Trusted Brands We Service in Santa Monica
We work with leading prefab and panelized ADU manufacturers and materials suppliers, and our Santa Monica customers regularly choose systems from Boxabl, Cover, and Dvele. Each matches a different lot condition: a compact side-yard ADU off a Mid-City alley, a garage-to-ADU conversion in Sunset Park, or a ground-up unit in Ocean Park with coastal massing constraints. We’re familiar with these systems’ structural requirements and how they interact with Santa Monica’s specific permitting process. Scheduling for Santa Monica projects is coordinated from our Los Angeles office, with crews serving Santa Monica locally.
Common Home Addition Contractor Problems We See in Santa Monica Homes
- Missing stem walls and seismic anchors on 1940s garages. A detached garage built in the 1940s usually sits on a slab with no stem wall and no anchor bolts. When you add a second story or convert it to living space, the foundation upgrade is mandatory, not optional, and it changes the budget if it wasn’t priced upfront.
- Cloth-wrapped wiring still in service. Pre-1960 Santa Monica homes often have original cloth-insulated branch circuits. Opening a wall for an addition triggers a code requirement to bring the exposed circuit to current standards. We price this as an allowance line item so you’re not surprised.
- Failed shower pan flashing rotting the floor framing. The marine layer keeps wood damp, and old shower pans in Santa Monica bathrooms have often been leaking for years. The damage hides behind tile until we open the wall. Our estimates include a contingency allowance for this known local failure mode.
- Coastal Zone review catching homeowners after plans are drawn. A large share of Santa Monica parcels sit inside the California Coastal Zone, adding a coastal development review layer for massing, visual character, and view preservation. Homeowners who planned their addition using Culver City rules hit a wall here. We check this before design starts, not after.
Pricing for Home Addition Contractor in Santa Monica, CA
Here are real numbers for Santa Monica’s market. A bathroom addition runs $45,000 – $85,000. A bedroom addition runs $80,000 – $160,000. A bump-out or small room addition runs $65,000 – $120,000. A full second-story addition over an existing footprint starts around $180,000 and goes up from there. What moves the price: foundation condition on pre-1960 garages, Coastal Zone review scope, whether a Rent Control Board consultation is triggered, and finish level. Every Lodgewick estimate includes a written breakdown with allowances for known local conditions like stem-wall pours, circuit replacement, and corrosion-resistant flashing. Call (254) 602-5618 and we’ll put a fixed price in writing before you commit to anything.
We Also Serve Cities Near Santa Monica
Our crews work throughout the Westside and into the South Bay. If you’re in Santa Monica, we’re already there. We also serve Venice, Pacific Palisades, Marina del Rey, and Culver City. Coastal Zone rules change block by block, so if you’re just outside Santa Monica proper, we’ll check your parcel against the right jurisdiction before quoting.
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 Home Addition Contractor in Santa Monica
If your parcel sits within the California Coastal Zone, yes. Santa Monica administers its own certified Local Coastal Program, which means additions in affected areas must satisfy coastal development standards for massing, visual character, and view preservation on top of standard zoning. We check your parcel’s status before design begins and tell you exactly what the extra layer adds to timeline and cost. Call (254) 602-5618 and we’ll check your address right away.
Because pre-1960 homes here routinely hide failed waterproofing, cloth-wrapped wiring, undersized framing, and garages without stem walls or seismic anchors. Once a wall is open, building code requires bringing exposed conditions to current standards. We handle this by inspecting before demo and writing allowances into your contract. Any condition we couldn’t see gets documented, priced in writing, and approved by you before we do the work. It’s the difference between an estimate that holds and one that blows up.
Sometimes, but Santa Monica’s R1 lot-coverage limits are tight. Many homeowners discover mid-design that their desired detached footprint would push them over allowable coverage. The workaround is often a second-story addition over an existing garage or rear wing. We calculate lot coverage in the first consultation, so you know which path is realistic before you pay for drawings.
Santa Monica’s marine layer keeps relative humidity elevated and delivers salt-laden air that corrodes exposed flashing, metal fasteners, and mini-split components measurably faster than even five miles inland. We spec corrosion-resistant hardware, robust vapor management, and exterior materials rated for coastal exposure as standard practice, not an upgrade. On a recent project off Pico near Lincoln, we closed out with a mini-split spec’d specifically for salt air.
We start with a Rent Control Board consultation. Santa Monica’s Rent Control Charter Amendment is one of the strongest local rent-control regimes in California, and a new addition tied to any rent-stabilized unit on the parcel usually needs that consultation before design starts. Ignoring it creates legal exposure that resurfaces during permitting or at sale. We bring it up early, document it, and build the consultation into your timeline so it’s not a surprise later.
Planning a home addition in Santa Monica? Call (254) 602-5618 now to schedule your free estimate. Russ Delmar and our Santa Monica crew will inspect your property, check your parcel against Coastal Zone and R1 coverage rules, and put a written price in your hand before any work begins. The Kingswell Guarantee covers every job: written price first, defined arrival window, clean site, and a written guarantee with a free return visit if the work fails within 365 days.
Written by Russ Delmar, Owner at Lodgewick ADU Builders, serving Santa Monica since 2010.