







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Laguna Hills, CA
An ADU in Laguna Hills typically costs between $120,000 and $400,000 depending on whether you go prefab or site-built, and most projects take between 4 and 12 months from permits to final walkthrough. We’re Benson ADU Builders, part of the Relay Home Co. family since 2006, and we handle ADU construction, home additions, and room additions across Laguna Hills with a written price before any work starts. Our local customers often tell us the same thing: they want someone who will name a number, put it in writing, and show up when they said they would. That is exactly how we work, and you can reach us any time at (903) 568-7222.
Why Laguna Hills Homes Are Different

Laguna Hills housing runs older than a lot of South Orange County buyers expect. Much of the original stock went up in the 1960s and 1970s, which means roof lines, foundations, and panel boxes can all need attention before an addition or ADU goes vertical. The terrain is also rolling in places, especially up toward the Nellie Gail Ranch area and along ridge lines – a sloping lot changes how we run drainage, where we can place a detached unit, and whether your garage conversation or second-story addition needs extra shoring.
The local climate helps. Mild summers and dry conditions mean fewer weather delays than coastal cities, but the sun exposure is real, so we plan window placement and insulation carefully to keep cooling costs down in August. If you live in a neighborhood with an HOA, you’ll also want to know that Laguna Hills has strict architectural guidelines in many communities, and we’ll help you understand what your association requires before you spend a dollar on plans. On a practical level, wider collector roads and standard lot sizes mean most Laguna Hills backyards can physically accommodate a detached ADU, but setbacks vary, and city planning staff will want a real site plan, not a sketch.
Our Main Laguna Hills Services
These are the two types of projects Laguna Hills homeowners call us about most often, and each has its own dedicated page with full pricing, process details, and local permitting notes.
ADU Builders in Laguna Hills
Adding an ADU in Laguna Hills usually means one of three paths: a prefab unit from a brand like Cover or Dvele, a garage conversion, or a site-built backyard home. The right path depends on your property’s setback, access for equipment, and how much site prep your lot requires. Older Laguna Hills homes with tight side yards often favor a compact prefab design, while larger lots in the Nellie Gail area can handle a fully custom build. We walk you through the tradeoffs, give you a written price, and handle everything from plans to final inspection. ADU Builders in Laguna Hills

Home Addition Contractor in Laguna Hills
A home addition in Laguna Hills means tying new square footage into an existing structure built 40 to 60 years ago, which is a different job than building from scratch. We check the existing foundation, roof tie-in, and panel capacity so the new space performs as one building. Many Laguna Hills additions are kitchens, primary suites, or family rooms, and we quote them line by line so you know exactly what the structure, finishes, and permit work cost before demo begins. Home Addition Contractor in Laguna Hills

Room Addition Contractor in Laguna Hills
Room additions are how most Laguna Hills families grow their home without moving. A new bedroom, home office, or expanded living space often fits within existing setback rules, but we still verify with city planning before we guarantee a footprint. Because many Laguna Hills lots slope gradually toward the street, we sometimes need to step the foundation or add retaining, which is exactly the kind of cost we put in the written estimate up front, not after we start digging. Room Addition Contractor in Laguna Hills

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 Laguna Hills
We’re authorized to build with leading prefab and materials brands including Cover, Dvele, Mighty Buildings, and Boxabl. That matters in Laguna Hills because it gives you a researched, factory-built option alongside traditional site-built construction. See our brands page for full specs and design comparisons.
Pricing for ADU Company in Laguna Hills, CA
| Service | Typical range in Laguna Hills |
|---|---|
| Prefab ADU (Cover, Dvele, Mighty Buildings, Boxabl) | $120,000 – $250,000 installed |
| Site-built detached ADU (studio to 1 bed) | $150,000 – $280,000 |
| Site-built detached ADU (2 bed) | $220,000 – $350,000 |
| Garage conversion ADU | $90,000 – $160,000 |
| JADU (attached junior ADU) | $60,000 – $110,000 |
| Home addition (ground floor, 200-400 sq ft) | $80,000 – $180,000 |
| Home addition (primary suite, 400-600 sq ft) | $140,000 – $280,000 |
| Room addition (single room, 150-250 sq ft) | $50,000 – $110,000 |
| Site prep and foundation work (sloped lot) | $10,000 – $40,000 |
| Permit fees and city processing | $3,000 – $12,000 |
Sloped lots and older foundations push most Laguna Hills prices toward the upper end of these ranges, because site work and structural upgrades are real costs that cheap bids often leave out until the job is underway. We give you one written price before work starts, and that number does not change unless you change the scope.
Neighborhoods We Serve in Laguna Hills
We work throughout Laguna Hills, and most areas are within a 20 to 30 minute drive for our crews. Here are the neighborhoods we get the most calls from:
- Nellie Gail Ranch
- Aliso Hills
- Beacon Hill
- Moulton Ranch
- Indian Hills
Service Area – Cities Near Laguna Hills
We also serve homeowners in the surrounding South Orange County communities. If your property is just outside Laguna Hills, we can likely help: Aliso Viejo, CA, Laguna Woods, CA, Mission Viejo, CA, and Lake Forest, CA. Scheduling is coordinated from the brand’s Los Angeles office, with local crews dispatched to Laguna Hills.
Serving Laguna Hills, CA - Our Local Coverage Area
We’re based in the Laguna Hills 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 Laguna Hills

We can typically schedule a site visit within a week of your call, and once plans are approved and permits are pulled, construction on a prefab ADU can start in as little as a few weeks. Site-built projects take longer due to foundation work and city inspections. Call (903) 568-7222 to get your project on the calendar. Estimates are free.
California state law limits what HOAs can do to block ADUs, but Laguna Hills associations can still enforce design standards, setbacks, and parking restrictions. We help you identify which rules apply to your specific neighborhood before you commit to a design. Call (903) 568-7222 and we’ll walk you through it.
Yes. We prepare and submit the full permit package to the City of Laguna Hills, follow it through plan check, and coordinate every inspection. You won’t be left calling the building department on your own. Call (903) 568-7222 to ask about your project; a real person answers around the clock.
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 Laguna Hills 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.



