A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Los Alamitos, CA
Fielding ADU Builders is the ADU and room-addition specialist serving Los Alamitos, CA, and the surrounding area. If you’re wondering what a Los Alamitos backyard unit, garage conversion, or attached suite actually costs, the direct answer is that most projects here fall between $180 and $450 per square foot depending on foundation work, utility runs, and finish level. We put that price in writing before any work starts. Call (361) 315-4177 to schedule a free estimate.
Why Los Alamitos Homes Are Different
Los Alamitos housing stock trends older than what you’ll find in newer Orange County developments. Many homes were built between the 1950s and 1970s, which means a few things for ADU and addition work. Older foundations may have settled, electrical panels are often 100-amp and undersized for a new living unit, and sewer laterals sometimes need replacement before the city signs off on new plumbing. We inspect for all of that during the estimate so the price you approve reflects the real job, not a surprise later.
The climate matters too. Los Alamitos sits close enough to the coast that marine air moves through most mornings, and that moisture shows up in framing and siding decisions. We spec materials that can handle the damp air, and when homeowners choose a prefab platform like Abodu or Cover, we coordinate site prep so the factory-built module lands on a foundation that drains right. Garage conversions in Los Alamitos often involve unpermitted past work, and we sort that out with the city before framing begins.
Our Main Los Alamitos Services
Los Alamitos homeowners call us most often about three things: building a detached ADU in the backyard, converting an existing garage into a rentable unit or family suite, and adding square footage to the main house. Each has its own dedicated Los Alamitos page below.
Room Addition Contractor in Los Alamitos
Room additions in Los Alamitos usually mean adding a master suite, a family room, or a second story over an existing single-story. The older post-war lots here tend to be compact, so we spend real time on setback requirements and how the addition will sit against the property line. We pull the permits, coordinate the trades, and write the price down before we start. Read the full breakdown on our Room Addition Contractor in Los Alamitos page.
Garage Conversion Contractor in Los Alamitos
Converting a garage in Los Alamitos is often the fastest path to a rentable one-bedroom or a comfortable home office. The catch on older lots is that the garage slab may not have a moisture barrier, and the existing electrical may not support a kitchen or laundry. We handle those corrections as part of the written quote. See what’s involved on our Garage Conversion Contractor in Los Alamitos page.
ADU Builders in Los Alamitos
Backyard ADUs in Los Alamitos come in three forms: detached new construction, attached conversions, and prefab units from companies like Dvele, Cover, or Abodu. Each has different city review timelines and different utility tie-in costs. We start every ADU estimate by walking the lot, measuring the actual setbacks, and checking where the sewer and power will run. Full details are on our ADU Builders in Los Alamitos 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.
Brands We Service in Los Alamitos
We build with James Hardie siding, coordinate Abodu and Cover prefab units, and work with Dvele for high-performance modular builds. Parts and finish materials are sourced through our Los Angeles office and delivered to Los Alamitos jobsites on schedule. Learn more on our brands page.
Pricing for ADU Company in Los Alamitos, CA
| Service | Typical range in Los Alamitos |
|---|---|
| ADU per square foot (site-built) | $180 – $320 |
| Prefab ADU per square foot | $250 – $450 |
| Garage conversion (full unit) | $120 – $190 per square foot |
| Room addition (ground-floor, single room) | $180 – $280 per square foot |
| Kitchen addition | $220 – $350 per square foot |
| Primary suite addition | $200 – $320 per square foot |
| Second-story addition | $250 – $400 per square foot |
| Foundation repair or new slab | $6,000 – $18,000 |
| Electrical panel upgrade to 200-amp | $2,500 – $5,500 |
| Sewer lateral replacement | $4,000 – $12,000 |
| Permit fees (city, plan check, school fees) | $5,000 – $18,000 |
What pushes Los Alamitos prices higher than a generic quote is usually one of three things: a 1950s-era foundation that needs seismic or moisture correction, an undersized electrical panel, or an old sewer line that has to be replaced before the city signs off. The Garrison Standard means the price goes in writing before any work starts, so the number you approve on day one is the number on the final invoice.
Neighborhoods We Serve in Los Alamitos
We work across Los Alamitos, including the neighborhoods around Los Alamitos Boulevard, Katella Avenue, and the blocks near the Joint Forces Training Base. Response time for a Los Alamitos estimate is typically within one to three business days.
- Old Town area near downtown Los Alamitos
- Subdivision streets off Katella Avenue
- Blocks near Los Alamitos High School
- Residential streets south of Cerritos Avenue
- Areas adjacent to the Los Alamitos Race Course
Service Area – Cities Near Los Alamitos
Besides Los Alamitos itself, we take calls from homeowners in Cypress, CA, Hawaiian Gardens, CA, Seal Beach, CA, and La Palma, CA. Each of these nearby cities shares the same post-war housing stock and coastal climate, and we apply the same written-price policy to every job.
Serving Los Alamitos, CA - Our Local Coverage Area
We’re based in the Los Alamitos 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 Los Alamitos
Most Los Alamitos ADU jobs can start within three to six weeks after the estimate and permit application are submitted. The city’s plan review timeline varies by project type, with prefab units often clearing faster than custom site-built ADUs. Call (361) 315-4177 to schedule a free estimate.
If your property sits in an HOA, you’ll need to check your CC&Rs even though California state law limits HOA authority to block ADUs. We handle the city permit side and can flag any HOA documents you need to submit. Call (361) 315-4177 to talk through your specific lot.
Yes. Every Los Alamitos project we take is permitted through the city, inspected, and closed out with a final sign-off. The written price includes the permit scope, and the Garrison Standard covers workmanship for a full year after completion. Call (361) 315-4177 for a free estimate.
If you’re ready to put a real number on your Los Alamitos ADU, garage conversion, or room addition, call (361) 315-4177. We’ll walk the lot, check the existing foundation, panel, and sewer, and hand you a written price before any work begins.
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 Los Alamitos Customers Say
"Solid job. Cabinet delivery was a week behind but they worked around it."
- Ben G."Insulation, drywall, and finishes were all well done. Feels like part of the house."
- Pete O."Built a detached ADU behind our house. The builder is a veteran and runs the site like a platoon: schedule posted, crew on time, everything labeled. Finished within a few days of the date."
- Ken W.
