How United Build Partners helps Irvine homeowners
We're an ADU advisory and contractor-matching service, not the construction company. We start with a free review of your Irvine property and goals, help you understand what the city's process actually requires, and — when it's a good fit — connect you with up to three contractors in our network suited to your project.
ADU rules and permitting in Irvine
Irvine's ADU rules build on the same statewide floor every California city follows — ministerial review, no discretionary hearings, and a 60-day clock on complete applications (see our California ADU laws guide). Irvine's own process adds a notably detailed application packet on top of that baseline.
What's specific to Irvine
- Size range: detached ADUs up to 1,200 square feet; attached ADUs capped at 50% of the primary home's floor area or 1,200 square feet, whichever is less; JADUs capped at 500 square feet.
- Height limits: up to 16 feet for a detached ADU, but up to 25 feet if the ADU is attached to the primary home — a notably taller allowance for attached units than many neighboring cities.
- Setbacks: generally 4 feet from side and rear property lines for both attached and detached units.
- Parking: capped at no more than one space per bedroom, with an exemption for properties within a half-mile of public transit.
- ADU Standard Plan Program: the city has introduced a pre-approved plan program using designs from licensed professionals, intended to speed up review and reduce design costs — confirm current plan availability with the city, since program rollout details can change.
What Irvine's application packet typically includes
- A completed Residential ADU (RADU) application and ADU Verification Form
- Signed affidavits from the property owner and applicant
- A School Fee Determination Form and, where applicable, a Transportation Corridor Agency form
- An Address Application for the new unit
Property and lot considerations
Irvine's neighborhoods were built as a series of master-planned "villages," which generally means more consistent lot sizes and setback patterns within a given village than you'd find in an older, organically-developed city — though the specifics still vary by village and individual parcel. Many Irvine HOAs have their own design review requirements layered on top of the city's process, so if your property is HOA-governed, it's worth reading our HOA ADU rules guide alongside this page.
Common ADU types for Irvine homeowners
Given Irvine's taller allowance for attached ADUs (up to 25 feet), homeowners with less backyard space sometimes find an attached ADU can accommodate more square footage vertically than a height-limited detached unit would. Homeowners with more yard space and a preference for full separation often still choose a detached ADU, especially where the Standard Plan Program applies. A Junior ADU remains the lowest-cost entry point for converting existing interior space.
Cost factors in Irvine
Construction costs in Irvine generally track the same $285–$350 per square foot range as the rest of our Orange County service area — see our full ADU cost guide. Using the Standard Plan Program where available can reduce design costs and speed up approval, though it also limits your layout options compared to a fully custom design.
Financing your Irvine ADU
Most homeowners fund construction through a HELOC, cash-out refinance, or dedicated construction loan — see our ADU financing overview for how each works and what to ask a lender.
Rental income and property value in Irvine
Irvine's strong renter demand — driven partly by UC Irvine and major regional employers — makes rental income a real consideration for many homeowners here, though actual achievable rent depends heavily on your specific village and unit, and we don't have a verified, current rent figure to quote. See our ADU rental income guide and property value guide for how to think through both carefully.
How our process works
Frequently asked questions
Irvine's process includes several city-specific forms — a Verification Form, signed affidavits, a School Fee Determination Form, and sometimes a Transportation Corridor Agency form — in addition to the standard application. A contractor experienced with Irvine's process can help you assemble the full packet correctly the first time.
Yes — Irvine generally allows up to 25 feet for an attached ADU, compared to 16 feet for a detached unit. This can matter if you're trying to maximize square footage on a lot with limited backyard space.
Possibly — many Irvine communities are HOA-governed with their own design review process. See our HOA ADU rules guide for what state law does and doesn't allow an HOA to restrict.