







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Alhambra, CA
Adding an ADU in Alhambra means working with a city where most lots were platted between 1910 and 1960, homes are closer together than in newer subdivisions, and the soil shifts with every wet winter. That combination changes how we design foundations, where we stage materials, and how carefully we protect your neighbor’s fence line. Sutton ADU Builders handles detached ADUs, garage conversions, and room additions across Alhambra, with a written price in your hands before any work starts. Call (472) 248-8213 to talk through your lot and get a straight answer on cost.
Why Alhambra Homes Are Different

Alhambra’s housing stock skews older. Walk the neighborhoods south of Main Street or up toward the hills north of Alhambra Road and you’ll see Spanish Revival bungalows from the 1920s, mid-century ranch homes, and the occasional 1980s infill. Older foundations are shallower than what current code requires, which means any ADU or addition we build over Alhambra’s clay-heavy soil needs a soils report and likely a deeper footing than the original house has. We plan for that from the first site visit.
Another Alhambra reality: lot sizes. Plenty of homes sit on 5,000 to 6,500 square foot parcels, which is enough for a detached ADU, but tight. A setback (the required gap between your new structure and the property line) of 4 feet for the side and rear is standard under California ADU law, and Alhambra enforces those measurements strictly during plan check. We survey, measure, and flag any encroachment before you spend money on drawings. The terrain also varies a lot for a city this size: flat near the 10 freeway, gently rising toward the north. Drainage design changes block by block, and we account for that on every Alhambra project.
Our Main Alhambra Services
Most Alhambra homeowners call us about one of two things: adding square footage to the existing house, or building a separate unit in the back. Here’s what each involves in this city.
Home Addition Contractor in Alhambra
A home addition in Alhambra usually means extending the back of the house or bumping out a side wall to add a bedroom, a larger kitchen, or a family room. Because many Alhambra homes were built before current seismic codes, the addition often triggers a requirement to brace and anchor the existing foundation where the two structures meet. We match rooflines, stucco texture, and window style so the new section doesn’t look bolted on. Get the full scope and pricing on our Home Addition Contractor in Alhambra page.

ADU Builders in Alhambra
A detached ADU in Alhambra is the fastest way to add a rentable unit or a private space for family. Typical projects here are 400 to 800 square feet, built in the rear yard with its own entrance, kitchenette, and bathroom. Many Alhambra lots can fit a one-bedroom ADU within the state’s 4-foot setback rule, but utility connections (sewer, power, water) often require trenching across the yard, which we price transparently. Details and real dollar ranges are on our ADU Builders in Alhambra page.

Room Addition Contractor in Alhambra
A room addition is typically a single bedroom, home office, or expanded bathroom done as an attached build, smaller in scope than a full home addition. In Alhambra, these often convert a covered patio or unused side yard into conditioned living space, which means extending HVAC ducts and upgrading insulation to meet Title 24 energy standards. We handle the permit drawings, the structural work, and the finish work under one written price. See the Room Addition Contractor in Alhambra page for costs and timelines.

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 Alhambra
We work regularly with Abodu, Cover, and Dvele prefab ADU systems in Alhambra. Each brand has different site-prep requirements, foundation types, and lead times, and we walk you through which one fits your lot size and budget before you commit. Learn more on our brands page.
Pricing for ADU Company in Alhambra, CA
| Service | Typical range in Alhambra |
|---|---|
| Detached ADU (400 – 500 sq ft) | $180,000 – $250,000 |
| Detached ADU (500 – 800 sq ft) | $220,000 – $320,000 |
| Garage conversion ADU | $120,000 – $190,000 |
| Prefab ADU (Abodu, Cover, Dvele) | $195,000 – $340,000 |
| Home addition (300 – 600 sq ft) | $165,000 – $310,000 |
| Room addition (single room) | $90,000 – $160,000 |
| Site work (utilities, grading, drainage) | $15,000 – $45,000 |
| Permit fees and plan check | $6,000 – $18,000 |
Prices in Alhambra run higher than the county average when the lot has grade changes, older sewer lines that need replacing, or a long trenching distance to the main. Every estimate we give is a written, line-item price before any work begins, so the number you approve is the number you pay.
Neighborhoods We Serve in Alhambra
We work across all of Alhambra, from the flat blocks near Valencia Avenue to the hillside streets north of Mission Road. Our crews know the permit counter at City Hall, the plan check rhythms, and the parking realities of Alhambra’s narrower residential streets.
- Midwick Tract area
- Alhambra Hills
- The Emery Park neighborhood
- North Alhambra (near Almansor Park)
- South Alhambra (near the 10 freeway)
Service Area – Cities Near Alhambra
We also serve homeowners in South Pasadena, CA, San Marino, CA, Monterey Park, CA, and San Gabriel, CA. If you’re just outside Alhambra, call and we’ll confirm whether your address falls within our local service range.
Serving Alhambra, CA - Our Local Coverage Area
We’re based in the Alhambra 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 Alhambra

We typically schedule Alhambra site visits within 3 to 5 business days of your call. A live person answers at (472) 248-8213 every day of the week, and we’ll coordinate a time that works around your schedule.
Alhambra follows California’s statewide ADU mandate, but the city still reviews setbacks, utility connections, and design compatibility with the neighborhood. We prepare and submit the full permit package, and our written price includes plan check fees so there are no surprises at the counter.
Yes. Every technician on your Alhambra project is background-checked, identity-verified, and photo-badged under our Threshold Verified standard. We send you the name and photo of each crew member before they arrive, and they’ll show a photo ID at your door, every time. Call (472) 248-8213 for a free estimate and a clear answer on your project.
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 Alhambra Customers Say
"They handled the drawings and the permit paperwork for us. All I had to do was pick the finishes."
- Rosa M."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.



