ADU Before & After in Orange County, CA
We could write a thousand words about our work. It wouldn’t do what these transformations do. A garage that stored boxes for a decade becomes a one-bedroom rental with a kitchen. A side yard that grew weeds becomes a studio with its own address. Below are real scenarios we’ve handled across Orange County, with the details that matter: what we started with, what we did, and what it costs when the math matters.
Recent Transformations
Detached Garage to One-Bedroom ADU in Santa Ana

The problem: a 480-square-foot detached garage that had become a storage unit for holiday decorations and old furniture. The foundation was sound, which matters more than most people think. We converted it into a one-bedroom ADU with a full kitchen, a stacked laundry closet, and a separate electrical subpanel. Everything to code, permits pulled, final inspection passed. Build time ran four and a half months, and the total came in around $180,000. That’s the range for a garage conversion this size in Orange County when the foundation and framing are salvageable. If we’d had to pour new footings, the number moves closer to $220,000. The homeowners now rent it for $2,200 a month.
Side-Yard Accessory Dwelling Unit for a Multigenerational Household in Fullerton

The problem: aging parents needed to live closer, but the main house had no room for a private suite. The side yard was wide enough at 14 feet, which let us build a 620-square-foot, two-bedroom ADU with its own entrance off the driveway. We matched the roofline to the main house so it doesn’t read as an afterthought. Exterior is James Hardie siding in a color that complements the existing stucco. The family got a layout with no steps, wide doorways, and a curbless shower. A project like this in Fullerton generally lands between $210,000 and $250,000 depending on site prep and utility work. The Kingswell Way applies here: written price before we started, a set arrival window for every phase, and a written guarantee covering the build for 365 days.
Prefab ADU Placement and Site Work in Huntington Beach

The problem: a backyard that sloped enough to complicate any foundation work, and a homeowner who wanted occupancy this year, not next. We leveled and compacted the pad, ran water, sewer, and electrical lines from the main house, and set a 400-square-foot prefab unit from Abodu. Site work in Huntington Beach ran roughly $45,000 to $60,000 because of the grading and a sewer line that needed to be relocated. The unit itself was purchased separately through Abodu, and we handled the set, the utility hookups, and the finishing work, including a small deck off the entry. Total occupancy timeline from permit to move-in: about six months. We work with Abodu, Cover, Dvele, Mighty Buildings, Boxabl, Plant Prefab, and Tuff Shed, and the choice depends on the lot and what the homeowner is actually trying to solve.
Two-Car Garage Conversion with JADU in Garden Grove

The problem: a growing household needed more room, but an addition was going to cost more than the property could justify. We converted the attached two-car garage into a 450-square-foot JADU (junior accessory dwelling unit), which is a smaller unit that attaches to the main house and shares some systems, but has its own entrance and a small kitchenette. JADUs run lower per square foot than detached builds because the structure already exists and the roof is already on. In Garden Grove, we typically see $120,000 to $160,000 for a JADU conversion of this size, depending on whether we’re moving a wall, upgrading the panel, or trenching new plumbing. The homeowners kept one wall of the original garage door opening as a window, which looks sharp and saved several thousand dollars in framing.
Second-Story Addition Above an Existing Garage in Orange

The problem: the lot was too narrow for a detached unit, but the garage had the footprint to support a second story. We framed a two-bedroom, one-bath ADU above the garage and added an exterior stairwell off the side yard so the unit has its own entrance. The garage below stays intact as storage. This is a heavier build, so we engineered the garage walls and footing to carry the load, and the city signed off on the structural plans before a single board went up. In Orange, expect a second-story ADU like this to run $280,000 to $340,000. That’s real money, which is why the 365-Day Done Right Promise matters: if something isn’t right after we hand over the keys, we come back. In writing, on every project.
Unused Carport to Studio ADU in Costa Mesa

The problem: a carport the homeowners hadn’t parked in for five years. It sat open, collected clutter, and offered nothing back. We enclosed it into a 350-square-foot studio ADU with a private bath, a kitchenette, and a new mini-split system for heat and air. The slab was already there, which saved serious money on foundation work. Costa Mesa allowed the conversion under state ADU guidelines and the city’s local overlay, and we pulled every permit. Final cost: about $135,000. For a studio this size where the slab and roof structure already exist, that’s a fair number. The trick is knowing before you start whether the roof framing will pass inspection without reinforcement. Ours did here. Sometimes it doesn’t, and that changes the estimate by $10,000 to $20,000. We tell you that before you sign, not after.
Want Results Like These?
Every one of these projects started with a phone call and a conversation about what the lot could actually do. We show up, we look at the site, we give you a written price before any work starts. No vague ranges when we’re standing in your yard, no change orders at the door. Call (350) 203-6060 to schedule your free estimate with Russ Delmar and the Lodgewick team in Orange County.
Frequently Asked Questions

Most ADU projects in Orange County land between $120,000 and $340,000. Garage conversions start around $120,000 to $160,000. New detached units from 400 to 620 square feet typically run $180,000 to $250,000. Second-story builds above existing structures go higher, from $280,000 to $340,000. Site conditions, foundation work, and utility connections move the number either direction. Call (350) 203-6060 and we’ll give you a written price based on your actual lot.
No. We put the price in writing before any work begins, and that’s the price you pay unless you change the scope. If we find something behind a wall that changes the plan, we discuss it with you and put any revision in writing before proceeding. The Kingswell Way says the price before the work, always, on every project, with no exceptions.
Yes. We pull all required permits and handle the inspections. Every project we build goes through the city’s final inspection, and we don’t hand over keys until it passes. Skipping permits is how homeowners end up with a unit they can’t insure, can’t rent, and can’t list when they sell. We don’t do that.
It’s our written guarantee that covers every build and repair for a full year. If the work fails within that 365-day period, we come back and make it right at no cost to you. The commitment is in writing on every project, before work begins, not as a verbal promise. That’s the Lodgewick standard.
Written by Russ Delmar, Owner at Lodgewick ADU Orange County, serving Orange County since 2010.


