Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Before
After
Before
After
Before
AfterFast, Reliable Home Additions & ADU Across Leon Valley
Home additions in Leon Valley typically run $45,000-$130,000 depending on scope, while a detached ADU generally lands between $90,000 and $220,000. What makes Leon Valley different from a job across the San Antonio line is simple: this city runs its own building department, and permits that look like Bexar County business actually have to go through Leon Valley City Hall on Bandera Road. We know that because we’ve pulled those permits. Call (877) 610-1318 and you’ll reach someone who understands how Leon Valley’s rules work before the first stake goes in the ground.
Why Barrett & Sons Construction Is Leon Valley’s Preferred Home Additions & ADU Company
Tom Barrett started this company in 1998, and his sons run the crews. When you hire us for a Home Additions & ADU project in Leon Valley, you’re hiring a family that lives twenty minutes away, not a franchise dispatching strangers from another state. Tom publishes his name, his address, and his license number. You can look it up before you sign anything, and plenty of Leon Valley homeowners have done exactly that.
The biggest difference we bring to Leon Valley roofing and construction work is jurisdictional awareness. Contractors who don’t know that Leon Valley issues its own permits through its own small inspection staff routinely lose days waiting on framing and rough-in approvals. We submit early, every time, because we’ve learned how this city’s review calendar actually moves. That’s not marketing fluff. It’s what keeps a garage conversion from sitting open to the weather for two extra weeks.
Every job includes permits pulled and inspections signed, written change orders before any scope change touches the work, and our 90-Day Done Right Promise in the contract. If it’s not done right, Tom comes back. One call.
Our Home Additions & ADU Services in Leon Valley
ADU Design & Permitting
Adding an attached or detached ADU in Leon Valley starts with a trip through Leon Valley City Hall, not San Antonio’s Development Services. We handle the full permit package, engineering, and site plan, and we coordinate with the city’s inspection staff from day one. For Leon Valley ranch homes on aging slabs, the design phase is where we catch foundation issues before they become change orders.
Garage Conversion ADU
A garage conversion in Leon Valley typically costs $30,000-$80,000, and most of the homes here are prime candidates: 1950s-1970s brick ranches with attached garages that already sit on existing slabs. The catch is that many of those slabs have moved over decades of Bexar County clay shrink-swell. We level and assess before framing, so your new living space doesn’t inherit a floor that pitches toward the alley.
New Detached ADU
Detached ADUs in Leon Valley run $90,000-$220,000, and the soil here demands more than a standard pier schedule. Properties near the Balcones Escarpment transition zone sit on clay that heaves dramatically in wet years and contracts in drought. We size footings and piers for that cycle, not for a textbook in another county.
Junior ADU & Interior Conversion
A junior ADU carved out of an existing Leon Valley ranch home, typically a converted primary suite or enclosed patio, runs $45,000-$90,000 depending on how much plumbing and electrical work the original 1960s-era systems will tolerate. Many of these homes still carry undersized panels, so a service upgrade is often part of the scope. We put that in writing before we start.
What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
A background-checked tech heads outLicensed & insured, dispatched right away.
- 4
You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Leon Valley
For windows and doors in Leon Valley on additions and ADUs, we install Simonton, Ply Gem, and PGT units, depending on what the project calls for. Impact-rated glazing matters here, especially on west-facing exposures that catch afternoon heat off the limestone shelf. We stock local parts for these brands, which means a broken sash or a delayed frame doesn’t stall your rough-in inspection while we wait on a truck from out of state. You can look up any of these brands by name. That’s the point.
Common Home Additions & ADU Problems We See in Leon Valley Homes
- Slab settlement from shrink-swell clay: Decades of drought-wet cycles along the Balcones transition have left many Leon Valley ranch slabs out of level. New addition footings have to be engineered for that movement, or the addition will crack away from the original structure within a few years.
- Un-permitted add-ons from prior decades: A lot of Leon Valley homes from the 1960s and 1970s have enclosed porches or converted garages that were never permitted. When we pull a new permit, the city often requires us to bring those old spaces up to current code before the new work can pass final inspection.
- Undersized electrical panels: Original 1950s-1970s panels in Leon Valley were sized for a much lighter load than a modern ADU demands. Adding a second dwelling unit frequently means a 200-amp service upgrade, and we include that in the written scope from the start.
- Permit jurisdiction confusion: Because Leon Valley is an independent municipality surrounded by San Antonio, contractors who assume they’re filing with Bexar County or COSA end up with rejected applications and lost weeks. We file with Leon Valley’s own Building Department on Bandera Road, correctly, the first time.
Pricing for Home Additions & ADU in Leon Valley, TX
A single-room addition in Leon Valley generally lands between $45,000 and $85,000. A full second-story addition on a 1960s ranch runs $80,000-$130,000, largely because the original footprint and foundation need reinforcement. Garage conversions sit at $30,000-$80,000. Detached ADUs start around $90,000 for a basic one-bedroom and climb to $220,000 for a two-bedroom with full kitchen and laundry.
What moves the number in Leon Valley specifically is soil prep and permitting. Foundation correction on clay-damaged slabs can add $8,000-$20,000 before framing begins, and the city’s inspection schedule can stretch a timeline by a week or more if permits aren’t filed early. We give you a written line-item quote before you commit, and every change gets a written change order. No allowance that isn’t on paper. Call (877) 610-1318 for a free estimate on your Leon Valley project.
We Also Serve Cities Near Leon Valley
Beyond Leon Valley, our crews work regularly in Lackland Air Force Base, Alamo Heights, Terrell Hills, and San Antonio. The same permitting discipline and foundation-aware building practices carry across the county line. If you’re nearby and considering a Kitchen Remodeling in Leon Valley or a Bathroom Remodeling in Leon Valley alongside your addition, we handle those trades in-house too.
Serving Leon Valley, TX - Our Local Coverage Area
We’re based in the Leon Valley service 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 - Home Additions & ADU in Leon Valley
We typically schedule free estimates in Leon Valley within a few business days, and because our crews live and work in the San Antonio metro, we’re on site regularly throughout the 78240 ZIP. Call (877) 610-1318 and we’ll get you on the calendar quickly.
Yes, we pull all permits through Leon Valley’s own Building Department on Bandera Road, not through San Antonio or Bexar County. We file early because Leon Valley’s inspection staff is small and scheduling can add days to a project if you wait. The permit inspector works for you, not for us, which is exactly how we like it.
A garage conversion ADU in Leon Valley typically runs $30,000-$80,000, with the final number driven by foundation condition, electrical panel capacity, and the finish level you choose. Call (877) 610-1318 for a written line-item quote, not a phone estimate that changes later.
Sometimes, and the reason is permitting and soil. Leon Valley’s independent permitting process can add review days, and the clay-heavy soils near the Balcones transition often require deeper footings or slab correction. We account for both in the written estimate before any work begins.
Every Barrett & Sons addition and ADU in Leon Valley carries our 90-Day Done Right Promise in writing. If something isn’t right, Tom Barrett comes back and makes it right. One call to (877) 610-1318, and we’re on it.
Written by Tom Barrett, Owner at Barrett & Sons Construction, founder since 1998.