A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Home Addition Contractor Across Tustin
Home additions in Tustin typically cost between $180 and $400 per square foot, with a full room addition running $85,000 – $180,000 and a second-story addition landing between $150,000 and $350,000 depending on scope. Those are real numbers we put in writing before the first crew member shows up. Lodgewick ADU Orange County handles room additions, second-story additions, garage conversions, and detached ADUs across Tustin, from the 1960s tract homes north of the 5 freeway to the newer hillside-adjacent builds in Tustin Ranch. Call (350) 203-6060 and a live person answers, day or night. We’ll give you a straight answer about your lot, your foundation, and what the job should actually cost.
Key Takeaways:
- Written price before any work starts, every time, with no change orders at the door
- 365-Day Done Right Promise: if it’s not right, we come back and make it right, in writing
- We know Tustin’s cast-iron drain lines, 100-amp panels, and clay soils before we quote
- Free estimates, live phone answer 24/7, and background-checked crews on every site
Why Lodgewick ADU Orange County Is Tustin’s Preferred Home Addition Contractor Company
Homeowners in Tustin keep calling us after another contractor burned them, which is exactly the pattern we built The Kingswell Way to fix. Say the price before the work, show up in the window given, leave the place cleaner than found, put the guarantee in writing, and come back if it fails. That’s not a slogan. It’s the operating procedure on every single project, and it’s why Tustin homeowners tell their neighbors about us.
We know the houses here. Ranch-style tract homes in Tustin Meadows with slab foundations and original cast-iron waste lines. Two-story stucco boxes in Columbus Square that need structural review before a second-story addition goes up. Flat clay lots where water pools against the foundation if the grading isn’t handled right. Our estimators walk the property, check the panel, look at the drainage, and only then put numbers in front of you.
We also know the difference between the city of Tustin and the county jurisdiction just outside city limits. If your property isn’t on city sewer, the whole scope changes, and it better change before you sign a contract, not after. We’ve been through enough Tustin additions to know which questions to ask up front.
Every project is led by Russ Delmar and backed by The Kingswell Guarantee. Every call goes to a person at (350) 203-6060, not a voicemail loop.
Room Addition Contractor in Tustin
Room addition contractor work in Tustin means pulling permits, verifying sewer versus septic, and building onto a slab foundation without cracking it in the process. A ground-floor room addition here usually runs $85,000 to $180,000 for a permitted, finished space with HVAC, electrical, and roofing tied into the existing structure. The price swings on panel upgrades, cast-iron drain replacement, and whether the lot gives you room to grade the addition away from the house.
On the older streets west of Red Hill Avenue, Tustin homes frequently hide cast-iron drain lines under the slab. Those need replacement before any bathroom addition, and that’s a cost most homeowners never see coming. We scope for it during the pre-construction walk, so it’s in the first written quote instead of hitting you after demo starts.
Bump-out additions are a smaller, faster way to gain a usable room off a kitchen or living area, and they work well on the flat lots that define Tustin’s suburban feel. We tie the roofline in cleanly, match the exterior with James Hardie siding where it fits, and keep the job permitted and inspected.
Tustin Slab-On-Grade Additions
Most Tustin homes built in the 1960s through 1980s sit on slab foundations, which changes how a room addition gets anchored. We saw-cut the slab, dowel into the existing footing, and pour new footings that meet current code, then make sure the grading moves water away from the new foundation line.
Bump-Outs on Tustin Tract Homes
A bump-out on a Tustin tract home can add 40 to 120 square feet without a full foundation rework. Useful office space, a breakfast nook, a reading corner. Faster build, lower price, same written guarantee.
Second Story Addition Contractor in Tustin
Second story addition contractor projects in Tustin start with a structural question: can the existing slab and first-floor walls carry a second level without reinforcement? Many 1960s – 1980s Tustin homes weren’t engineered for vertical additions, so we bring in a structural engineer before we quote. A permitted second-story addition here typically runs $150,000 to $350,000 depending on square footage, roofing, and whether the existing 100-amp panel needs upgrading for the added HVAC and lighting loads.
The upside in Tustin is real. With 5,000 to 7,000 square foot lots and land values pushed up by proximity to Irvine and the Great Park, building up is often the only way to add serious square footage without eating the small backyard. We’ve helped Tustin homeowners double their living space while keeping the yard their kids play in.
On a ranch-style home in the Tustin Meadows tract, our crew scoped a detached ADU with a second-story addition over the garage. During pre-construction, we discovered original cast-iron waste lines under the slab that had corroded at the slab penetration. We replaced them with ABS before pouring the new bathroom group, then framed the addition with James Hardie siding to match the 1970s exterior.
That’s the difference between quoting from a truck and walking the property.
Second-Story Over Existing Rooms
When a Tustin homeowner wants to add bedrooms over the living area, we verify ceiling height, wall framing, and foundation capacity first. Some houses need shear-wall upgrades; some don’t. You’ll know before we sign.
Second-Story Over a Garage Addition
Building over the garage is one of the more efficient ways to add square footage in Tustin without touching the footprint. We check the garage slab, the header above the garage door, and the fire separation, then quote accordingly.
Trusted Brands We Service in Tustin
We work regularly with leading prefab and panelized manufacturers, including Abodu, Cover, and Dvele, matching each to the lot size, timeline, and budget of the Tustin homeowner. For properties where the addition needs to blend with an older tract home, we move toward traditional stick-frame with materials like James Hardie siding. Our familiarity with these systems means we can quote accurately on them from the start instead of learning on your job. Tustin customers get the same written price and 365-Day Done Right Promise no matter which system fits the build.
Common Home Addition Contractor Problems We See in Tustin Homes
- Cast-iron drain lines under slab foundations. Homes west of Red Hill Avenue and in Tustin Meadows often have original cast-iron waste lines that have corroded at the slab penetration. Any bathroom addition means replacing them first or fighting sewer gas and slab leaks later.
- 100-amp electrical panels on 1960s – 1980s tract homes. A new second-story room with HVAC, outlets, and lighting can push an old 100-amp panel past its limit. Overlooking the upgrade means a failed final inspection and a surprise $3,500 – $6,000 change order.
- County septic setbacks on acreage properties outside city limits. If your Tustin-area property sits outside city sewer service, a detached ADU or room addition may need to clear county septic setbacks. Those setbacks can shrink the buildable footprint and change the addition’s placement before you ever break ground.
- Clay-heavy soils and flat-lot drainage. Tustin’s clay soils heave when wet and shrink when dry. If runoff from the addition’s roofline isn’t directed away from the new foundation, cracks show up within a few seasons. We grade and drain every addition as part of the scope.
Pricing for Home Addition Contractor in Tustin, CA
A permitted room addition in Tustin runs $85,000 – $180,000. Second-story additions land between $150,000 and $350,000. Bump-outs are smaller and typically start around $40,000. The biggest variables are the foundation type, whether the sewer line under the slab needs replacing, and whether the electrical panel has to come up to code. We give you a line-item written quote before work starts, and the number on that page is the number you pay. The Kingswell Guarantee says a free return visit if the work fails within 365 days. Call (350) 203-6060 to schedule a free estimate and see the numbers for your specific house.
We Also Serve Cities Near Tustin
We handle Home Addition Contractor projects for homeowners in Tustin and the surrounding cities, including Home Addition Contractor in Tustin, Santa Ana, Costa Mesa, Midway City, and Lake Forest. If you’re just outside the Tustin city line but still in the OC area, call us. We’ll tell you if we can get a crew to your street.
Serving Tustin, CA - Our Local Coverage Area
We’re based in the Tustin 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 About Home Addition Contractor in Tustin
Your addition has to clear county septic setbacks, which can reposition the ADU on the lot and reduce the buildable area. We pull county records and walk the leach field during pre-construction, then place the addition where it actually fits instead of where the sketch looked good. Call (350) 203-6060 for a review of your specific property.
In most 1960s – 1980s Tustin tract homes, yes. A second-story room with its own HVAC, lighting, and outlets usually exceeds what an original 100-amp panel can carry. We include the panel upgrade in the written quote before work starts, so there’s no failed-inspection surprise. If your panel handles the load, we’ll say that too and leave it alone. Get an exact answer with a free estimate.
Cast-iron drain lines under the slab. Homes west of Red Hill Avenue and in Tustin Meadows regularly have original cast-iron waste lines that have corroded at the slab penetration, and a bathroom addition won’t pass inspection until they’re replaced with ABS. Budget roughly $4,000 – $9,000 for the replacement, depending on run length and access. We scope for it before quoting. Call (350) 203-6060 and we’ll check your house.
Santa Ana winds mean dry, gusty days that push fire risk up in the hillside-adjacent areas like Tustin Ranch. We lean on fire-resistant exterior materials, including James Hardie fiber cement siding, and we make sure roof underlayment and venting meet current fire codes. It’s not an upsell; it’s the right material for the area.
Yes. We’ve pulled combined permits for detached ADUs with attached garages or shop space on Tustin-area lots, which keeps the review process moving and avoids sequencing complications. The scope gets written clearly in your line-item quote, and the same 365-Day Done Right Promise covers the whole build.
Contact Your Tustin Home Addition Contractor
If you’re looking at an addition on a Tustin lot, start with a free estimate from a contractor who writes the price down before the work starts. Lodgewick ADU Orange County serves all of Tustin, including Tustin Meadows, Tustin Ranch, Columbus Square, and the older neighborhoods west of Red Hill Avenue. Call (350) 203-6060 to talk through your project. Russ Delmar and the team will walk the property, walk you through the scope, and put the whole thing in writing before a single nail is driven.
Written by Russ Delmar, Owner at Lodgewick ADU Orange County, serving Tustin and the surrounding Orange County area since 2010.
