Fast, Reliable ADU Design & Permitting Across Irvine
ADU design and permitting in Irvine, CA typically costs $8,500-$24,000 for the full design-build package, drawings through final inspection, and most projects clear both village association ARC and City of Irvine permits in 90-150 days. We’re Irvine‘s design-build studio for homeowners who need the permit set done right the first time, not a designer and contractor pointing at each other when something is off. Our scheduling team operates from our Los Angeles office, and our crews serve Irvine neighborhoods including Woodbridge, Northwood, Turtle Rock, Woodbury, and Portola Springs with same-week site assessments. Call (562) 263-3350 to schedule yours - estimates are free, and the written price arrives before any work starts, per Haven Standard Clause 1.
Why Ellery ADU Studio Huntington Beach Is Irvine’s Preferred ADU Design & Permitting Company
We’ve designed, permitted, and built 900+ ADUs since 2015, the year California’s ADU laws shifted, and a significant share of those have been in Irvine’s master-planned villages. Nadia Ellery, our founder, built this studio specifically to eliminate the designer-versus-builder blame gap that derails most ADU projects in HOA-governed cities like Irvine.
Our Irvine clients receive a documented photo record on every site visit, not a summary of how it felt. Under Haven Standard Clause 5, the scope is locked at signing - no door-side upsells, no scope creep. The 365-Day Done Right Promise is in writing before the project starts: if the finished ADU is not built to the permitted drawings, we make it right.
Dispatch to Irvine runs same-week for site assessments. We know the difference between Woodbridge’s ARC portal and Turtle Rock’s fee schedule because we’ve submitted to both. A live person answers calls 24/7 - no voicemail queue, no callback promise that doesn’t materialize.
Our ADU Design & Permitting Services in Irvine

Site Assessment
Every Irvine lot tells a different story. We measure your garage slab thickness, check terrace grading on sloped village parcels, and document existing utility locations before quoting. In Portola Springs, we’ve found garage slabs as thin as 3.5 inches - below the 4-inch minimum for conversion - which changes the foundation line item by $3,000-$5,000. We photograph everything and send you the record within 48 hours. No surprises at permit.

ADU Design & Blueprints
Our ADU Design & Permitting team produces the full permit set: architectural plans, structural calcs, MEP layouts, and Title 24 energy compliance documentation. For Irvine, we run HOA compatibility review and City of Irvine submittal in parallel - a sequence that doesn’t exist in Santa Ana or Anaheim. Your village ARC must sign off on exterior design before the city will accept your permit application, so we design to both standards simultaneously rather than sequentially.

Permit Application
City of Irvine building permits for ADUs run $2,800-$4,200 depending on valuation, plus plan check fees. We handle the full submittal, correction cycles, and inspection scheduling. Our permit specialists know Irvine’s specific requirements: fire separation between garage conversions and primary dwellings, Title 24 HERS verification for all conditioned space, and the city’s particular detail on egress window sizing for basement or lower-level units.

HOA & Zoning Compliance
This is where Irvine differs from every neighboring city. Every single-family neighborhood sits inside an Irvine Company-affiliated village association whose Architectural Review Committee controls matching rooflines, stucco colors, trim materials, and setback aesthetics. California AB 670 bars outright bans, but ARCs still legally impose design standards that add 30-60 days to every project. We navigate the village portal, fee schedule, and review timeline specific to your ARC - Woodbridge’s process differs from Northwood’s, which differs from Turtle Rock’s. We do not pull city permits until ARC sign-off is documented.

Title 24 Energy Compliance
Irvine’s inland location pushes summer highs to 90-95°F regularly. Title 24 treats a properly sized split-system heat pump as mandatory for all conditioned ADU space, not optional. We model your specific envelope - existing garage insulation, roof pitch, window area - and specify equipment that passes HERS verification the first time. Wall units fail. We don’t specify them.

What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Irvine
We specify and coordinate prefab and modular systems from Abodu, Plant Prefab, and James Hardie within the same single contract that covers your design and permitting. For Irvine’s ARC-governed villages, brand selection often hinges on exterior finish compatibility - James Hardie siding, for instance, matches the stucco-and-trim vocabulary of most Irvine Company villages with less custom detailing than a site-built alternative. We coordinate factory delivery to your lot, crane access on 4,500-7,500 sq ft parcels, and the Title 24 documentation that accompanies each system. All under one written price, Haven Standard Clause 1.
Common ADU Design & Permitting Problems We See in Irvine Homes

- Pulling city permits before ARC sign-off. Contractors new to Irvine routinely stall projects this way. Each village association has its own submission portal, fee schedule, and review timeline. City inspectors will flag an ADU built without documented HOA approval, requiring costly aesthetic remediation even on otherwise code-compliant structures. We sequence ARC first, city second.
- Ignoring grading and drainage on terrace lots. Irvine’s low annual rainfall - under 14 inches - masks runoff problems until the first winter storm. Poorly sited slabs on graded terraces crack. We specify thickened-edge slabs with French drains tied to existing swales before quoting.
- Specifying wall-unit HVAC on garage conversions. The 90-95°F inland summer highs make a split-system heat pump a mandatory Title 24 line item, not an upgrade. Unconditioned garage spaces or wall-unit retrofits fail HERS verification and require redesign.
- Designing detached units without addressing foundation on thin slabs. Most Irvine garages were built on 4-inch slabs without vapor barriers or insulation. Conversions require full retrofit: vapor barrier, rigid insulation, and conditioned envelope. We scope this before quoting, not after demo.
Pricing for ADU Design & Permitting in Irvine, CA
A typical garage conversion ADU in Irvine runs $125,000-$185,000 all-in, drawings through final inspection. A new detached ADU in Irvine on an existing lot runs $195,000-$340,000 depending on size, foundation conditions, and utility trenching length. Junior ADUs and interior conversions start at $85,000-$140,000.
Design and permitting fees, included in those totals, typically break out as: site assessment and documentation ($800-$1,200), full permit set and architectural plans ($4,500-$8,500), HOA/ARC navigation ($1,500-$3,000 where applicable), Title 24 energy modeling and HERS verification ($1,200-$2,400), and City of Irvine permit and plan check fees ($2,800-$4,200). Grading and drainage work on sloped village parcels adds $3,500-$8,000. Foundation upgrades on thin or cracked slabs add $3,000-$7,500.
Every project is quoted with a written price before any work begins - Haven Standard, Clause 1. The words “call for a quote” do not appear on this site. Call (562) 263-3350 for your written estimate.
We Also Serve Cities Near Irvine

Our crews work throughout Orange County, including ADU Design & Permitting in Irvine and neighboring Tustin, Santa Ana, Orange, and Newport Beach. Each city carries its own permitting landscape - Santa Ana has no ARC layer, Newport Beach has coastal commission considerations - and we scope accordingly before quoting.
Serving Irvine, CA - Our Local Coverage Area
We’re based in the Irvine 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 - ADU Design & Permitting in Irvine

Yes - every Irvine single-family neighborhood sits inside an Irvine Company-affiliated village association whose Architectural Review Committee must sign off on exterior ADU design before the City of Irvine will accept your permit application. We run HOA compatibility review and city submittal in parallel to compress the timeline, but ARC approval is a hard gate. Call (562) 263-3350 to discuss your specific village’s process.
The ARC controls exterior aesthetics: roof pitch and material, stucco color and texture, trim profiles, window style, and setback appearance from street view. They cannot ban ADUs under AB 670, but they can legally require design harmony with the primary dwelling. We design to your village’s specific design guidelines from the first elevation sketch to avoid second submission cycles.
Irvine’s 90-95°F inland summer highs and Title 24 compliance requirements make conditioned space mandatory, and most Irvine garages were built unconditioned without vapor barriers or insulation. The retrofit includes: vapor barrier, rigid slab insulation, wall and ceiling insulation to R-value spec, and a split-system heat pump sized to the conditioned volume. Wall units fail HERS verification. We scope this before quoting, not after opening walls.
Many do - especially on graded terrace soils common in villages like Turtle Rock and Woodbury. Irvine’s low rainfall masks drainage problems until winter storms concentrate runoff against new slabs. We specify thickened-edge slabs with perimeter French drains tied to existing swales where the site assessment indicates terrace soils or visible slope. This adds $3,500-$8,000 to the project, scoped before quoting.
We specify and coordinate Abodu, Plant Prefab, and James Hardie systems within our single-contract design-build model, with exterior finishes selected for ARC compatibility in your specific village. Factory-built systems require the same City of Irvine permits and Title 24 documentation as site-built - we handle both tracks. Call (562) 263-3350 to match a system to your lot and village guidelines.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Irvine since 2015.