Fast, Reliable Garage Conversion ADU Across Santa Ana
A garage conversion ADU in Santa Ana typically runs $95,000-$165,000 all-in, drawings through final inspection, with most detached garage projects in the $110,000-$145,000 range. We’re Nadia Ellery’s team at Ellery ADU Studio Irvine, and we serve Santa Ana from our Los Angeles coordination office - crews are local, permits are pulled at Santa Ana’s Community Development counter, and every project starts with a written price before any work begins.
Santa Ana’s alley-grid neighborhoods, older housing stock, and SB 897 amnesty pathway make garage conversions here fundamentally different from new construction in surrounding Orange County cities. We measure setbacks, check utility clearances, and inspect electrical and plumbing systems before quoting - so the price you sign is the price you pay.
Call (657) 233-9738 to schedule your free estimate.
Why Ellery ADU Studio Irvine Is Santa Ana’s Preferred Garage Conversion ADU Company
We’ve designed, permitted, and built over 900 ADUs since 2015 - the year California’s ADU laws shifted - and a significant share of our Santa Ana work involves legalizing existing unpermitted structures, not starting from scratch. That’s a specialized skill set most design-build studios in wealthier neighboring cities rarely need.
Our Santa Ana clients receive a documented photo record on every site visit, a permit set treated as the core product (not an afterthought), and the 365-Day Done Right Promise backed in writing before the project starts. Under Haven Standard Clause 1, the written price is locked at signing - no door-side upsells, no scope creep.
A live person answers our phones 24/7. Dispatch and scheduling are coordinated from our Los Angeles office, with crews serving Santa Ana neighborhoods including Midtown, Logan, and Delhi directly.
We also offer a Free Second Opinion on any written estimate already in hand - bring us another contractor’s scope and we’ll flag what’s missing, what’s optimistic, and what Santa Ana’s permit counter will actually approve.
Our Garage Conversion ADU Services in Santa Ana
Detached Garage Conversion
This is the most common project type in Santa Ana. The city’s post-WWII tract homes and 1920s bungalows frequently have detached garages at the rear property line, accessed by alley. In central Santa Ana neighborhoods like Midtown and Logan, our first site visit always includes measuring alley setback (typically 5 feet from alley centerline) and checking for overhead utility lines - two factors that can kill or reshape a garage conversion before design even starts. A typical detached garage conversion in Santa Ana runs $110,000-$145,000 all-in.
Attached Garage Conversion
Attached garages in Santa Ana’s older stock often share a wall with the main house, which simplifies utilities but complicates fire separation and sound attenuation. We specify James Hardie fire-rated exterior materials where required, and we verify the existing foundation and slab can handle the conversion load. Most attached conversions in Santa Ana fall between $95,000-$125,000.
Garage JADU (Junior ADU)
A Garage JADU is carved from an existing garage space while the remainder stays garage - no new footprint, faster permitting. Santa Ana’s small-lot bungalows are ideal candidates. The owner must reside in either the main house or the JADU, and we handle the owner-occupancy affidavit as part of our permit set. Garage JADUs in Santa Ana typically run $75,000-$105,000.
Carport Conversion
Carport conversions require full enclosure, foundation verification, and often new electrical service. In Santa Ana’s mild climate, carports were common in 1950s and 1960s tracts. We assess whether the existing slab meets current code thickness and whether the open sides can be enclosed within setback limits. These projects range $85,000-$120,000.
Garage Partition & Bathroom Add
Some Santa Ana homeowners want to split a two-car garage, keeping one bay for storage and converting the other to a studio with bath. This requires careful plumbing routing - Santa Ana’s older galvanized supply lines and cast-iron drains usually need replacement. We price the partition, the bath rough-in, and the utility upgrades as separate line items so you see exactly where the money goes.
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 Santa Ana
Ellery ADU Studio specifies and coordinates prefab and modular systems from Abodu, Cover, and Dvele within our single-contract model - the same written price covers drawings, permitting, and installation. For site-built garage conversions in Santa Ana, we frequently specify James Hardie fiber-cement siding for its fire resistance and ember-rated performance during Santa Ana wind events. Every material choice is documented in the permit set and backed by our 365-Day Done Right Promise.
Common Garage Conversion ADU Problems We See in Santa Ana Homes
- Outdated electrical service that fails first inspection. Santa Ana’s 1920s-1960s housing stock typically has 60-100 amp panels with cloth-wrapped or aluminum wiring. The moment walls open for inspection, the panel upgrade becomes mandatory - not optional. We inspect the service before quoting and write the upgrade into the contract as a named allowance.
- Alley setback and overhead utility conflicts. That detached garage in Logan or Midtown may sit within the 5-foot alley centerline setback, or overhead power lines may run directly through the alley access. Either condition can force redesign or kill the project. We measure and photograph both during the first site visit.
- Rotted framing from years of irrigation runoff. Santa Ana’s alley-side garages often have rear sill plates degraded by sprinkler overspray and poor drainage. We find this only when walls open, which is why our contracts include a structural repair allowance priced per linear foot - activated only if needed, with photo documentation and written approval before any framing is touched.
- Unpermitted prior work that triggers code upgrades. Santa Ana’s history of informal conversions means we regularly open walls to find illegal wiring, missing shear panels, or failed waterproofing that was never disclosed. Under Haven Standard Clause 5 (No Surprises), we stop, photograph, write a change order, and get your approval before proceeding - every time.
Pricing for Garage Conversion ADU in Santa Ana, CA
Garage conversion ADUs in Santa Ana typically run $95,000-$165,000 all-in, drawings through final inspection. Detached garage conversions, the most common type here, usually fall in the $110,000-$145,000 range. Attached conversions run $95,000-$125,000. Garage JADUs, which preserve part of the garage, start around $75,000.
What moves the number: electrical panel upgrades (add $8,000-$15,000), foundation repair or replacement (add $12,000-$25,000), plumbing replacement from galvanized to copper or PEX (add $4,000-$8,000), and fire-rated materials for detached units in high-wind zones. We inspect for all of these before you sign, write them as named allowances, and activate them only with your written approval and photo evidence.
Under Haven Standard Clause 1, every project is quoted with a written price before any work begins. No “call for a quote” - the quote is the point. Call (657) 233-9738 for your free estimate.
We Also Serve Cities Near Santa Ana
Our Garage Conversion ADU in Santa Ana crews also work in Tustin, Orange, Garden Grove, and Costa Mesa. Each city has different setback rules, permit timelines, and inspection protocols - we adjust the permit set accordingly rather than recycling the same drawings.
Serving Santa Ana, CA - Our Local Coverage Area
We’re based in the Santa Ana 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 - Garage Conversion ADU in Santa Ana
Yes - California’s SB 897 amnesty provisions allow legalizing pre-existing unpermitted structures during conversion, and this is one of the most common project types we handle in Santa Ana. The amnesty pathway requires proving the structure existed before the current code cycle, bringing electrical, plumbing, and structural elements to current standard, and passing full inspection. We navigate this at Santa Ana’s Community Development permit counter regularly. Call (657) 233-9738 to discuss whether your structure qualifies - estimates are free.
Almost certainly yes - Santa Ana’s 1920s-1960s housing stock with 60-100 amp service cannot handle the additional load of a kitchen, bathroom, and HVAC in an ADU. We inspect your panel during the first site visit and write the upgrade into your contract as a named allowance, typically $8,000-$15,000. You see the number before signing, not after walls are open. Call (657) 233-9738 for an exact quote on your service.
Measure the distance from alley centerline to your garage wall (typically 5 feet minimum required) and photograph any overhead utility lines running through the alley access. Either condition can force redesign or kill the conversion outright. We verify both during our free site visit before any design work begins. Call (657) 233-9738 to schedule - we’ll bring the measuring tape and the camera.
The Santa Ana winds bring periodic extreme fire-weather conditions that make ember-resistant vents and fire-rated exterior materials a practical necessity, not just a code formality. We specify James Hardie fiber-cement siding and ember-rated vent screens on all detached conversions in Santa Ana’s wind zones. These materials cost more than standard vinyl but prevent ember intrusion that can ignite a structure. Your permit set includes the fire-rated specification; your written price includes the material difference. Call (657) 233-9738 for project-specific pricing.
We stop work, photograph the condition, and write a change order with a firm price before touching anything. On a 1948 bungalow in the Logan neighborhood, our crew opened the garage walls for a detached conversion and found cloth-wrapped wiring tapped off a 60-amp panel plus a rear sill plate rotted from years of alley-side irrigation runoff. We paused, wrote a change order with photos, and got the homeowner’s approval before replacing the panel to 200 amps, sistering the framing, and rerouting the circuits - all under an SB 897 amnesty permit that legalized the existing structure at the same time. No surprise bills, no verbal estimates. Call (657) 233-9738 - our Garage Conversion ADU team documents everything.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Santa Ana since 2015.