ADU & Room Additions in Irvine, CA
Real square footage — designed, permitted, and built by one team.
ADUs & Additions for Irvine homeowners
Irvine homeowners trust A1 Builders for ADU & room additions. Irvine's planned communities often come with HOA requirements; we work within them, coordinate approvals, and keep job sites tidy for both interior remodels and exterior work, start to finish.
Irvine's HOA-governed communities like Woodbridge and Northwood often have specific design and approval requirements for ADUs and additions, and we manage that coordination alongside the city permit process so your project clears both hurdles without delay.
Whether you need space for a growing family, an aging parent, a home office, or rental income, adding square footage is one of the biggest-impact projects a homeowner can take on — and one of the most complex to get right. A1 Builders manages ADUs and room additions end to end: feasibility and design, structural engineering, the full permit set, and every trade from foundation to final finish. California's streamlined ADU rules have made adding a unit more accessible than ever, and we know how to navigate LA and Orange County's specific permitting process so your project moves without stalling in plan check.
We serve Woodbridge, Turtle Rock, Northwood, University Park, and the rest of Irvine (Orange County).
ADUs & Additions problems we solve in Irvine
- Needing more living space without the cost and upheaval of moving
- Wanting rental income or multigenerational living space but unsure where to start
- An underused garage that could become real, permitted living space
- Juggling a separate architect, engineer, and contractor with no one owning the outcome
Our ADU & room additions process
- 1
Free Feasibility Consult
We assess your lot, existing structures, and local rules, and lay out what's realistically possible.
- 2
Design & Engineering
We develop plans and structural engineering sized to your goals, lot, and budget.
- 3
Permitting
We prepare and submit the full plan set and manage plan check with the city.
- 4
Foundation, Framing & Systems
Footings, framing, plumbing, electrical, and HVAC built to code and inspected at every stage.
- 5
Finish & Walkthrough
Interior and exterior finishes completed, final inspection passed, and the space handed over — backed by our workmanship warranty.
Recent ADUs & additions work
ADU & Room Additions in Irvine — FAQs
Ready for ADU & room additions in Irvine?
Book a free, no-pressure consultation. We'll talk through your goals and budget, then follow up with a clear, fixed-price proposal.

