ADU builder · San Gabriel, CA
ADU builder in San Gabriel.
Design, permits, financing and construction from one local team. 600+ ADUs delivered across greater LA, including nearby Alhambra, South Pasadena, Monrovia & Pasadena.
Licensed & insured · Construction from $275/sq ft · 5.0★ rated
Building an ADU in San Gabriel
San Gabriel is a small city that grew up around Mission San Gabriel, and its housing runs from older homes near the historic core to postwar houses on quieter residential streets. Families here often want space for parents or grown kids without leaving the neighborhood. ADU permits have moved up and down: state housing reports show about 106 in 2024 and about 51 in 2025, with about 99 ADU units in applications in 2025.
Our closest work is next door in Alhambra, plus a 1,025 sq ft two-bedroom in South Pasadena designed to match a 1913 home, a Craftsman ADU in Monrovia and an attached two-bedroom in Pasadena.
Design, permits and construction stay with one team. You get a fixed quote before construction, a single project manager and help comparing financing options.
ADUs in San Gabriel: quick facts
Updated November 2026
- Who issues ADU permits
- City of San Gabriel
- Our construction rates
- $275, $300 or $325 per sq ft (basic, mid-range, luxury); garage conversions $235–$285 per sq ft
- Example cost
- A 600 sq ft one-bedroom runs about $165K–$195K in construction
- Size limits under state law
- Detached ADUs up to 1,200 sq ft on many lots; junior ADUs up to 500 sq ft inside the home
- Permit decision
- State law requires a decision within 60 days of a complete application
- Who builds it
- ADU Resource Center: design, permits and construction by one team, 600+ ADUs delivered, office in Glendale
ADU rules change. We confirm the current rules for your lot on the free consultation.
Real projects nearby
ADUs we've built near San Gabriel.
Hear it from our clients
Homeowners on building their ADU with us
More stories on our testimonials page.
Local know-how
What to know before building in San Gabriel.
City permits, updated rules
San Gabriel's Community Development Department reviews ADUs. The city adopted updated ADU rules in April 2024, so older guides you find online may be out of date. We work from the current code.
Historic homes
The city has a historic preservation ordinance and a specific plan for the Mission District. Homes on the city's register may need an ADU that respects the original design.
Design first
Start with our floor plans or a blank page. We size the unit to your lot coverage and the bedroom count you need, then price it.
Garage conversions
If your home has a detached garage, converting it usually costs less than building new, and you don't have to replace the parking you give up. See garage conversion cost.
What it costs
ADU cost in San Gabriel
We build at a flat rate per square foot: $275 (basic), $300 (mid-range) and $325 (luxury) finishes. Here's what that means for common sizes. Construction only; design, permits and city fees are quoted separately on your consultation.
| ADU size | Basic | Mid-range | Luxury |
|---|---|---|---|
| 400 sq ft studio | ~$110K | ~$120K | ~$130K |
| 600 sq ft 1-bedroom | ~$165K | ~$180K | ~$195K |
| 800 sq ft 2-bedroom | ~$220K | ~$240K | ~$260K |
| 1,000 sq ft 2–3 bedroom | ~$275K | ~$300K | ~$325K |
Get a number for your exact size: ADU cost calculator · Browse ADU floor plans · Converting a garage? See garage conversion cost.
Free consultation
Start your San Gabriel ADU.
Tell us about your property. We'll confirm what's buildable, give you a real price range and walk through financing within 1 business day.
Questions
San Gabriel ADU questions, answered.
Still have a question? Ask us during your free consultation.
Who reviews ADU plans in San Gabriel?
San Gabriel is its own city, so ADU applications go to its Community Development Department, not to LA City or the county. The city updated its ADU rules in 2024 to follow state law. We prepare the plans, submit them and answer the city's comments.
Do you offer ADU design in San Gabriel?
Yes. Our in-house designers draw the ADU for your lot, either from scratch or starting from one of our 39 floor plans, and the same team takes it through permits and construction. Many clients sit down with a designer at our Glendale office and adjust the layout in 3D before it goes to engineering.
What if my house is historic?
San Gabriel has its own historic preservation ordinance, and the area around the mission has a specific plan. If your home is a listed resource or sits in a historic area, the ADU may need to follow extra design standards. We check that early and design the unit to fit the house.
How much does an ADU cost in San Gabriel?
Our construction rate is $275, $300 or $325 per sq ft for basic, mid-range or luxury finishes. A 600 sq ft one-bedroom comes out near $165K–$195K. Garage conversions start at $235 per sq ft because they reuse the existing structure.
How big can my San Gabriel ADU be?
Under state law, many lots can take a detached ADU up to 1,200 sq ft, and a junior ADU of up to 500 sq ft can go inside the house. San Gabriel's own limits depend on bedroom count and lot coverage, and the rules change from time to time. We confirm the size your lot allows on the consultation.
Free consultation
Ready to build your ADU in San Gabriel?
Tell us about your property and we'll confirm what's buildable, give you a real price range and lay out financing on one free call.
