Custom homes & ADUs
built in Southern California.

California's housing laws now let most homeowners add an accessory dwelling unit to their property, and most Southern California lots can accommodate one. SR Design and Build handles ADU projects end-to-end: feasibility check against your lot's setbacks and utilities, design, structural engineering, permits with the local jurisdiction, foundation, framing, mechanical, finishes and final inspection. Typical detached ADU timelines run 3 to 5 months from permit issuance to move-in ready.

We also take on full custom-home builds for owners developing their own lot. That means we work with your architect (or recommend one), handle Title-24 compliance, coordinate soils engineers and civil work, and run the project through plan check. Our custom home builds are 1,800 to 4,500 square feet and run anywhere from eight to fourteen months depending on scope and city.

1. Feasibility. We review your lot, zoning, setbacks and utility access to confirm what's actually buildable, and give you a realistic budget range before you spend a dollar.

2. Design & engineering. We bring in architecture, structural and Title-24 as needed. You see renderings and a scope with real material allowances before we go to permit.

3. Permits. We submit, run plan check, revise if needed, and pay fees. You stay out of the city planning office.

4. Construction. Site work, foundation, framing, mechanical rough-ins, inspections, finishes. Weekly schedule, weekly photos, one lead on site.

5. Final & keys. Final inspection, walkthrough with you, punch list closed, one-year craftsmanship warranty from the day you move in.

Custom construction has more ways to go wrong than any remodel. We insure against the usual ones: a single licensed builder (CSLB #1120021) carries the entire scope, we don't disappear between the permit stage and the first dig, and the cost picture we quote you is the cost picture we hold to. If scope changes mid-build — and on a custom project, sometimes it does — you get a written change order with the new number before we proceed.

We work with your lender if you're financing the build, send draw-ready invoices on schedule, and give your appraiser clean documentation. For ADUs specifically, we handle every piece of the state-mandated process so you don't have to learn California's ADU rules on your own time.

ADU and custom-home construction throughout the Inland Empire and north Orange County. Primary service area: Riverside, San Bernardino, Ontario, Rancho Cucamonga, Corona, and Moreno Valley. We also work in Fontana, Jurupa Valley, Chino and the surrounding corridor.