ADU Company in Costa Mesa, CA
Costa Mesa homeowners call us most often for kitchen remodeling that unlocks cramped 1950s and 1960s floor plans, and for ADU projects on lots where unpermitted garage conversions complicate the path to a legal rental unit. The mild coastal climate means kitchens don’t fight humidity the way they do in Newport Beach, but the real challenge is working around mid-century framing, older plumbing runs, and floor plans that were never designed for how families cook today. Fullerton ADU Builders has served Costa Mesa since 2017, and we’ve learned exactly where these older homes hide surprises behind the drywall. Call (877) 801-4497 to talk through your project.
Why Costa Mesa Homes Are Different
Costa Mesa’s housing stock splits into two distinct realities. West of the 405 in 92627, you’ll find 1950s and 1960s single-story ranch and mid-century tract homes on generous lots, many with mature trees that shade the house but limit ADU placement. East of the freeway in 92626, South Coast Metro’s mix of 1960s tract homes and newer condos means tighter lots and, in many neighborhoods, HOA rules that add a layer of review before any ADU or major remodel can proceed.
The climate shapes every job. Costa Mesa rarely sees frost, so heating demand is minimal, but south- and west-facing rooms absorb serious afternoon sun. A kitchen remodel here should account for cross-ventilation and solar orientation, not just cabinet layout. On the ADU side, that same sun exposure drives window placement, overhang design, and the choice of exterior cladding. We specify James Hardie fiber cement products on ADU exteriors because they handle coastal sun and the occasional Santa Ana wind without warping or fading.
The other Costa Mesa-specific reality is unpermitted work. In 92627’s older tract neighborhoods, many garages were converted to living space decades ago without City approval. When we start an ADU project that touches a garage, we regularly uncover those old conversions, and they have to be legalized or removed before Costa Mesa’s planning staff will sign off on the new unit. It’s a fixable issue, but it changes the timeline and budget, and it’s why pre-application meetings with the City matter so much here.
Our Main Costa Mesa Services
Two services dominate the calls we get from Costa Mesa homeowners, and both come back to the age of the housing stock and the value of the lots.
ADU Builders in Costa Mesa
Adding an ADU in Costa Mesa means navigating two very different lot realities: the spacious 92627 parcels where a detached unit fits comfortably but may require design review, and the tighter 92626 lots near South Coast Metro where site-built construction competes with existing structures and mature landscaping. State law allows ADUs up to 1,200 square feet and 16 feet tall, but Costa Mesa’s local ordinance often triggers design review for two-story units in established neighborhoods, so we recommend pre-application meetings before committing to a plan. We’re brand-agnostic, which means we match the unit to the lot, not the other way around. Learn more on our ADU Builders in Costa Mesa page.
Bathroom Remodeling in Costa Mesa
Bathrooms in Costa Mesa’s 1950s and 1960s homes are almost always undersized by modern standards, and many still sit on original cast-iron drain lines that have decades of scale and corrosion inside. A bathroom remodel here is rarely just tile and fixtures. It often means opening the floor to replace the waste line, re-framing to steal space from a hallway closet, and re-venting to meet current code. Homes in 92627 with slab foundations add an extra layer of work, since moving a toilet or tub drain means cutting concrete. Full details are on our Bathroom Remodeling in Costa Mesa page.
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.
Kitchen Remodeling in Costa Mesa
Kitchen remodeling in Costa Mesa is usually about undoing a 1950s or 1960s floor plan. The original kitchens in 92627 ranch homes were built as closed-off workrooms with a single window and a door to the dining room. Families today want an open flow into the living space, an island, and real ventilation. The mild climate means we can tie a kitchen remodel to outdoor living in ways that don’t apply inland: pass-through windows, larger garden-facing glazing, and layouts that move the kitchen toward the backyard. This is the core of our work for Fullerton ADU Builders, and the page for our broader practice is Kitchen Remodeling.
Galley Kitchen Opening
Signs you need it
You’re cooking in a narrow run of cabinets with one person’s worth of counter space, while everyone else squeezes past to reach the back door.
What it costs in Costa Mesa
Removing the dividing wall between a 1950s galley kitchen and the living area in Costa Mesa typically runs $18,000 to $35,000, depending on whether the wall is load-bearing and how much ceiling work is needed to hide the beam.
How we do it
We assess the wall’s structure, install a header or beam if required, relocate plumbing and electrical that ran through the wall, patch the ceiling to a flush finish, and build cabinetry continuity across the new open span.
Full Kitchen Renovation
Signs you need it
Your cabinets are original to the house, the layout fights how you actually cook, and you’re working around failing appliances, worn counters, or a floor that’s seen better decades.
What it costs in Costa Mesa
A full kitchen renovation in Costa Mesa, including new cabinetry, counters, flooring, and appliances, typically costs $55,000 to $110,000, with premium finishes and major layout changes pushing the top of that range.
How we do it
We demo to the studs, update plumbing and electrical to current code, install new cabinetry and counters, lay new flooring, and finish with appliance installation, backsplash, and punch-list detailing.
Kitchen Island Addition
Signs you need it
You have unused floor space in the middle of the room but no work surface, no casual seating, and no place for the family to gather while you cook.
What it costs in Costa Mesa
Adding a kitchen island with plumbing for a sink in Costa Mesa runs $8,000 to $18,000, depending on slab work for the drain, countertop material, and electrical for outlets or a cooktop.
How we do it
We map the floor system to locate the best drain path, core or trench the slab if needed, run electrical through the floor or a stub wall, then set the cabinetry and countertop as a single integrated unit.
What Kitchen Remodeling Costs in Costa Mesa
| Item | Typical range in Costa Mesa |
|---|---|
| Galley kitchen opening (remove wall, add beam if needed) | $18,000 – $35,000 |
| Full kitchen renovation (cabinets, counters, floors, appliances) | $55,000 – $110,000 |
| Kitchen island addition (with sink and electrical) | $8,000 – $18,000 |
How long does a kitchen remodel take in Costa Mesa?
A full kitchen remodel in Costa Mesa typically takes 8 to 12 weeks from demo to final walkthrough; a wall opening runs 3 to 5 weeks. Structural changes and unpermitted discoveries can add time. Call (877) 801-4497 for a schedule tied to your exact scope.
Do you pull permits for kitchen remodels in Costa Mesa?
Yes, we pull all required Costa Mesa permits for structural, electrical, and plumbing work, and we schedule the inspections. Unpermitted kitchens are a liability at resale and a red flag for buyers. Call (877) 801-4497 to get your project started the right way.
Brands We Service in Costa Mesa
Costa Mesa kitchens and ADUs see their share of coastal sun and occasional wind, so we standardize on proven products. James Hardie fiber cement cladding, Abodu and Plant Prefab ADU units, and Tuff Shed structures are all products we work with regularly. See our brands for the full breakdown of what we install and why we trust each one.
Pricing for ADU Company in Costa Mesa, CA
| Service | Typical range in Costa Mesa |
|---|---|
| Galley kitchen opening (remove wall, add beam if needed) | $18,000 – $35,000 |
| Full kitchen renovation (cabinets, counters, floors, appliances) | $55,000 – $110,000 |
| Kitchen island addition (with sink and electrical) | $8,000 – $18,000 |
| Prefab ADU (attached, 1-bedroom) | $180,000 – $290,000 |
| Prefab ADU (detached, 1-bedroom) | $190,000 – $330,000 |
| Prefab ADU (detached, 2-bedroom) | $240,000 – $390,000 |
| Site-built ADU (detached, 1-bedroom) | $280,000 – $420,000 |
| Site-built ADU (detached, 2-bedroom) | $340,000 – $500,000 |
| Bathroom remodel (full) | $25,000 – $60,000 |
| Bathroom remodel (primary suite) | $45,000 – $90,000 |
In Costa Mesa, two things push prices higher than other Orange County cities: unpermitted garage conversions that must be legalized before a new ADU can proceed, and two-story units that trigger design review. We give a written line-item quote before work starts, and we hold to it unless you change the scope.
Neighborhoods We Serve in Costa Mesa
Our crews move through Costa Mesa every weekday, which keeps response times tight. We know the tract layouts, the common foundation types, and the recurring code issues in each area.
- Mesa Verde (92626)
- College Park (92626)
- Westside Costa Mesa (92627)
- Eastside Costa Mesa (92627)
- South Coast Metro (92626)
Service Area – Cities Near Costa Mesa
Fullerton ADU Builders works throughout Costa Mesa and the surrounding coastal and inland communities. If you’re in Newport Beach, CA, Fountain Valley, CA, Huntington Beach, CA, or San Joaquin Hills, CA, the same team and the same upfront pricing apply.
Serving Costa Mesa, CA — Our Local Coverage Area
We’re based in the Costa Mesa 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 Costa Mesa
Once permits are approved, we can typically begin within 2 to 4 weeks, depending on current scheduling. Costa Mesa’s planning and building review process is the bigger variable, especially for ADUs that need design review. Call (877) 801-4497 to get a realistic start date for your project.
We prepare the documentation Costa Mesa HOAs typically request, including site plans, elevation drawings, and exterior material specifications. HOA review runs parallel to, not instead of, the City’s permit process. We’ll flag HOA requirements early so they don’t stall your ADU later.
We cover all Costa Mesa ZIP codes: 92626, 92627, and 92628. That includes Mesa Verde, College Park, Westside Costa Mesa, Eastside Costa Mesa, and the South Coast Metro corridor. If you’re not sure whether you’re in our service area, call (877) 801-4497 and we’ll confirm it in under a minute.
Ready to get a real number for your Costa Mesa project? Call Fullerton ADU Builders at (877) 801-4497 for a free estimate. We’ll walk your lot or your kitchen, explain the Costa Mesa-specific code path, and give you a written line-item quote before you commit to anything.
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 Costa Mesa Customers Say
"Detached unit in the back yard. Utilities trenched, separate meter, and it passed final on the first inspection."
— Erin Ziegler"Garage conversion to a one bedroom unit. He handled the plans, the city submittal, and every round of corrections. Took six months from first meeting to final inspection and he never once made the permit process my problem."
— Tim Padgett"The kitchenette layout he suggested made better use of the space than the one on our original sketch."
— Marisol Guzman