Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
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AfterFast, Reliable Home Additions & ADU Across Timberwood Park
Adding square footage in Timberwood Park carries a complication most contractors don’t mention until the excavator is already on your lot: the Edwards Aquifer Recharge Zone. A home addition in Timberwood Park typically runs $45,000 to $130,000, and part of that cost is site work that simply doesn’t exist five miles south. If your contractor doesn’t know Bexar County’s impervious cover rules, doesn’t know the bedrock is shallow enough to need rock-breaking equipment, your project stalls, and your budget goes with it. We’ve been working these lots long enough to plan for it before the first truck arrives. Call (877) 610-1318 for a free estimate, and we’ll walk your property with you.
Why Barrett & Sons Construction Is Timberwood Park’s Preferred Home Additions & ADU Company
Tom Barrett started this company in 1998, and his sons run the crews. When we say owner-operated, we mean the name on the truck is the name on the permit application. In Timberwood Park, our roofing work matters more than most places, because we’re one of the few crews that regularly works with Bexar County Development Services rather than guessing at San Antonio’s permitting schedule. Around here, a wrong permit submission sends you back weeks, not days.
Our windows and doors in Timberwood Park customers tend to find us the same way: a neighbor mentions us, or they see one of our job signs on a street like Borgfeld Road or Bulverde Road and call. We’ve completed additions and ADUs across the 78260 zip code, from the larger lots along Ammann Road to the custom homes tucked into the hills off Blanco Road. What they get is a crew that shows up when promised, and pricing that arrives in writing as a change order before anything changes.
Every job we take in Timberwood Park benefits from our 90-Day Done Right Promise. It’s written on the contract, not hidden in fine print. If something isn’t right, Tom comes back and makes it right with one call. We also pull permits and get inspections signed on every eligible addition or ADU project. The permit inspector works for you, not for us, and we like it that way.
Our Home Additions & ADU Services in Timberwood Park
ADU Design & Permitting
Building an accessory dwelling unit in Timberwood Park means working with Bexar County’s rules, not San Antonio’s, and that distinction trips up a lot of out-of-area contractors. We handle the full design and permit path, including the site-coverage calculation that impervious cover limits require in the aquifer zone. If your lot’s already near the 15-30% cap, we’ll tell you on the first visit, not midway through framing.
Garage Conversion ADU
A garage conversion in Timberwood Park often runs $30,000 to $80,000, and it’s one of the more efficient ways to add a rentable unit or a private suite for an aging parent. Many of the homes here were built from the late 1980s through the mid-2000s with oversized garages that convert well. We check the slab, the roofline, and the existing electrical service before we ever quote, so the number you hear is the number you’ll pay.
New Detached ADU
A new detached ADU in Timberwood Park is a bigger investment, typically $90,000 to $220,000, and the shallow Edwards limestone under your lot is the biggest wild card. Standard excavation tools won’t get through it. We plan for hydraulic rock-breaking or diamond-bit drilling in our quotes so there’s no surprise change order. The result is a freestanding unit with its own address, its own utility tie-in, and its own rent check if you choose to lease it.
Junior ADU & Interior Conversion
For homeowners who don’t want a separate building, a junior ADU or interior conversion turns a finished attic, a bonus room, or part of a first-floor wing into a self-contained living space. In Timberwood Park, where many homes have 2,500 to 5,000 square feet but aging family members who don’t want stairs, this is often the fastest path to multi-generational living. We coordinate the plumbing, the kitchenette, the egress, and the permit.
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 Timberwood Park
We don’t put mystery materials in your home. On Timberwood Park additions and ADUs, you’ll see the same names we’d put in our own houses: Techo-Bloc or Cambridge pavers on anything outdoors, and Quikrete products on the concrete work the aquifer zone makes so particular. When a specific material matters to the job, we tell you what it is, what it costs, and why we chose it before we order it. No generic “materials included” line that hides the real story.
Common Home Additions & ADU Problems We See in Timberwood Park Homes
- Edwards Aquifer site-coverage compliance: In the recharge and contributing zone, impervious cover is capped by Bexar County and SAWS rules, often at 15-30% of lot area. Additions and new ADUs trigger a site-coverage calculation that city contractors don’t think about until it’s too late.
- Limestone bedrock surprises: The shallow Edwards rock under most of Timberwood Park means foundation work and utility trenches need rock-breaking equipment, not standard excavation. A low quote from an out-of-area contractor usually means they haven’t planned for it.
- Flash-flood drainage on sloped lots: Timberwood Park sits on the Balcones Escarpment transition, where intense storms push water fast through limestone draws and easements. Every addition or ADU we build here includes storm drainage engineering, and we won’t pour a slab until it’s right.
- Wrong-jurisdiction permit filings: Timberwood Park is unincorporated Bexar County, not San Antonio. Contractors who file through COSA’s portal lose weeks. We file with Bexar County Development Services from day one.
Pricing for Home Additions & ADU in Timberwood Park, TX
Here’s where real numbers help. A room addition in Timberwood Park runs $45,000-$130,000. A garage conversion ADU typically falls between $30,000 and $80,000. A new detached ADU is $90,000-$220,000. What moves the number: the size of your addition, whether we’re tying into stone veneer and a Texas Ranch roofline or a simpler gable, how much rock-breaking your lot requires, and whether we’re handling a full second story or a single-level bump-out.
We quote fixed prices in writing, and every allowance is on paper before work starts. An allowance that isn’t on paper is a surprise waiting for a date, and we don’t work that way. Call (877) 610-1318 for a free estimate, and we’ll give you a line-item number you can actually plan around.
We Also Serve Cities Near Timberwood Park
Our crews work the whole corridor around Timberwood Park, including Home Additions & ADU in Timberwood Park proper, plus Fair Oaks Ranch, Live Oak, Boerne, and Windcrest. If you’re in one of those communities, call the same number and we’ll schedule a property walk the same way.
Serving Timberwood Park, TX - Our Local Coverage Area
We’re based in the Timberwood Park 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 Timberwood Park
A home addition in Timberwood Park typically costs $45,000 to $130,000. The final number depends mainly on square footage, whether you’re adding a second story, and how much rock-breaking your lot needs. Call (877) 610-1318 for a free line-item estimate, and we’ll walk your property before we quote.
Yes. Every eligible ADU or addition we build in Timberwood Park includes permits pulled through Bexar County Development Services and inspections signed before we call the job done. This is unincorporated Bexar County, not San Antonio, and filing into the right jurisdiction saves you weeks.
Yes, and we plan for it from the first site visit. The shallow Edwards limestone under Timberwood Park usually requires hydraulic rock-breaking or diamond-bit drilling rather than standard digging. We include that cost in our written estimate, so there’s no surprise change order once work begins.
Most garage conversions in Timberwood Park take roughly 10 to 16 weeks from start to final inspection, depending on the electrical upgrade and the county permit schedule. We’ll give you a written timeline with your estimate and update it in writing if anything changes.
Every addition and ADU we build in Timberwood Park is covered by our written 90-Day Done Right Promise. If something isn’t right, one call brings Tom back to make it right. That’s not a warranty buried in a binder; it’s written on the contract, and we honor it every time.
Contact Barrett & Sons Construction in Timberwood Park
If you’re ready to talk about a room addition, a garage conversion, or a detached ADU on your Timberwood Park property, call (877) 610-1318 and ask for a free estimate. There’s no trip charge inside the county, and a live person answers the phone. If you’ve already got a written estimate from another contractor, bring it and we’ll give you a free second opinion. We’re also glad to help with Kitchen Remodeling in Timberwood Park or Bathroom Remodeling in Timberwood Park if your project expands beyond the addition itself.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Timberwood Park and the surrounding Hill Country since 1998.