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 Bee Cave
Home additions and ADU construction in Bee Cave typically run $45,000 to $130,000 for a room addition and $90,000 to $220,000 for a detached ADU, and the permitting process takes four to eight weeks before a shovel ever hits dirt. We know this because Tom Barrett and his sons have been pulling permits, cutting limestone, and passing final inspections across the 78738 ZIP for years. If you’re planning a second-story addition off Bee Cave Parkway or a detached ADU behind a home near Falconhead, call (877) 610-1318 for a free estimate with a written, line-by-line scope before you commit to anything.
Why Barrett & Sons Construction Is Bee Cave’s Preferred Home Additions & ADU Company
We’re the owner-operated Home Additions & ADU team that shows up with our name on the truck, not a franchise’s. Tom Barrett founded the company in 1998, and his sons run the crews today. When you call, a live person answers – 24 hours a day, seven days a week, not a call center in another state. The crew members who walk onto your Bee Cave property are background-checked and uniformed, and they carry the Barrett name on their shirts because they’re accountable to it.
The Bee Cave homeowner we work for has usually been burned before. They’ve had a national outfit quote one price over the phone and hand them a different invoice at the door. That’s why we put every scope, every allowance, and every price change in writing before work moves forward. If the number changes, you get a written change order with your signature on it. Not a surprise at the end. That’s how we’ve earned a strong local reputation across Bee Cave, Lakeway, and the surrounding Hill Country – one signed permit, one passed inspection, one verified address at a time.
Tom publishes his name, his address, and his license number. Look them up before you sign anything. Ask anyone on your street about us. We live close enough that if something isn’t right, we want to hear about it and we’ll come back. Every completed job carries a written 90-Day Done Right Promise. If it’s not done right, one call brings Tom back.
Our Home Additions & ADU Services in Bee Cave
Here’s what we actually do for homeowners in Bee Cave – and how the local conditions change the way each one gets built.
ADU Design & Permitting
Bee Cave enforces impervious cover caps at the parcel level, often 20 to 30 percent depending on zoning. Your permitted ADU starts with an up-front lot survey and an impervious cover calculation before any design work happens. We handle that first step because skipping it means the city rejects the permit before a single footing gets dug. Our team prepares the drawings, the drainage plan, the structural engineering, and the permit package, then walks it through City of Bee Cave review until it’s signed.
New Detached ADU
A ground-up detached ADU in Bee Cave usually lands between $90,000 and $220,000, and the two wildcards are rock excavation and stormwater compliance. Most of 78738 sits on Austin Chalk and Edwards limestone, so utilities, footings, and drainage trenches go through rock cutting more often than not. We plan for that with a geotechnical check and a drainage strategy that meets LCRA and City of Bee Cave stormwater ordinances before we bid the job. You get a fixed number, not a surprise after the excavator hits stone.
Garage Conversion ADU
Converting an attached or detached garage into an ADU in Bee Cave typically costs $30,000 to $80,000. The advantage here is that the roof and slab already exist, so the impervious cover impact stays low. That matters on lots already near their 20 to 30 percent cap. We handle the structural reinforcement, insulation, plumbing, electrical, and the interior build-out, and we pull permits and schedule inspections on every conversion.
Junior ADU & Interior Conversion
A junior ADU – often a bedroom suite with its own entrance, kitchenette, and bath inside or attached to the main house – is the fastest, most cost-effective way to create rental income or a private space for family in Bee Cave. These projects usually stay within the home’s existing footprint, which keeps the impervious cover question off the table entirely. That can make the difference between a permit issued in weeks and one stuck in review for months.
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 Bee Cave
We install materials our customers can look up by name, not mystery brands off the back of a van. For driveway approaches, patios, and drainage surfaces on Bee Cave ADU projects, we work with Techo-Bloc and Belgard permeable pavers that satisfy the city’s stormwater requirements while handling the Hill Country’s temperature swings. For foundation and site work, Quikrete and Oldcastle concrete products hold up to the limestone substrate and the occasional flash flood drainage load. We keep local suppliers in the Bee Cave area stocked with what our crews need, which means faster turnaround when your permit clears and the build window opens.
Common Home Additions & ADU Problems We See in Bee Cave Homes
- Skipping the impervious cover calculation: Homeowners design an addition or ADU, fall in love with the drawings, then learn the lot is already at its 20 to 30 percent cap and the city won’t issue the permit. We run the survey and the calculation first, before design, so you never pay for plans that can’t be built.
- Underestimating rock excavation: A footing or utility trench that hits continuous Austin Chalk can turn a $45,000 room addition into a $65,000 job overnight. We include a geotechnical assessment up front and price the rock work honestly.
- Framing to the wrong wind-load tables: Bee Cave sits on the Balcones Escarpment, and ridge-top lots fall under Exposure C wind-load requirements that are stricter than standard tables. Framing a second-story addition or ADU to the wrong rating fails the structural inspection after rough-in, and that’s a costly teardown-and-redo.
- Ignoring the drainage obligation: Flash Flood Alley is real, and City of Bee Cave stormwater ordinances are actively enforced. A ground-up ADU needs a compliant drainage plan – often including a swale, retention, or permeable surface – or the final inspection won’t be signed. We route drainage to LCRA standard on every build.
Pricing for Home Additions & ADU in Bee Cave, TX
Here are the real numbers for Home Additions & ADU work in Bee Cave, based on the jobs we’ve built and bid across the 78738 ZIP:
| Project Type | Typical Bee Cave Price Range |
|---|---|
| Home Addition | $45,000 - $130,000 |
| ADU Construction | $90,000 - $220,000 |
| Garage Conversion | $30,000 - $80,000 |
What moves the number? Footprint and foundation type, rock excavation depth, wind-load engineering on ridge-top lots, drainage infrastructure, and the finish level you choose. A 600-square-foot detached ADU with a basic interior on flat ground costs less than a two-story addition with a full bath and kitchen on a limestone shelf. We give you a fixed, line-item scope after the survey and design review. No allowances that aren’t on paper, no verbal agreements that disappear later. Call (877) 610-1318 for a free estimate on your specific project.
We Also Serve Cities Near Bee Cave
While this page focuses on Bee Cave, our crews regularly work in Home Additions & ADU in Bee Cave and the surrounding communities: Lakeway, Lago Vista, Shady Hollow, and Austin. If you’re just outside the 78738 ZIP, call us and we’ll let you know if we can help.
Serving Bee Cave, TX - Our Local Coverage Area
We’re based in the Bee Cave 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 Bee Cave
Bee Cave sits on the Balcones Escarpment, and many lots in 78738 fall under Exposure C wind-load requirements, which are stricter than the standard Exposure B tables used in flatter parts of Travis County. The structural engineer stamps the wind-load calculations with your specific lot’s exposure category, and the city’s building inspector verifies the framing against that stamped set during the structural inspection after rough-in. A compliant quote includes that engineering, and we pull the permit and schedule the inspection so it gets signed. Call (877) 610-1318 to get your project scoped with the right engineering from day one.
Bee Cave tracks impervious cover at the parcel level, and most residential lots are capped between 20 and 30 percent depending on zoning. Any new structure, driveway extension, or hardscape addition counts toward that cap. If your lot is already near the limit, a new detached ADU’s roof and any added patio or walkway will push you over, and the city will reject the permit. We run an up-front survey and impervious cover calculation before we start design so we know whether your build fits, what has to be offset with permeable surfaces, and what the permit package needs to include. Call (877) 610-1318 for a free lot review.
Yes, in most cases you do. Bee Cave is in Flash Flood Alley on the Balcones Escarpment, and the city enforces stormwater ordinances alongside LCRA drainage requirements. A ground-up ADU changes how water moves across your lot, so the permit package needs a drainage plan showing that runoff will be managed – often with a swale, retention feature, or permeable surface. We handle that as part of ADU Design & Permitting, and the drainage plan goes in with the permit application. Call (877) 610-1318 and we’ll walk you through what your specific lot will require.
It can, because a permitted ADU with signed inspections and documented wind-load and drainage compliance is lower risk on paper than an unpermitted structure or one built to the wrong standard. When you file a claim or a premium review, the insurance carrier sees a city-approved build with engineering stamps and inspected framing. That documentation matters in Bee Cave, where storm and wind events are a real exposure. We hand you every permit, every inspection signature, and every engineering stamp when the job is done. Call (877) 610-1318 to get your project scoped and permitted the right way.
A cheap ADU quote in Bee Cave usually leaves out the survey, the impervious cover calculation, the drainage plan, the wind-load engineering, and the rock excavation allowance. What looks like a $90,000 detached ADU becomes a $140,000 job once the city rejects the permit, the excavator hits limestone, or the structural inspection fails after rough-in. A compliant quote includes every one of those line items in writing before work starts. Every change after that comes as a written change order with your signature on it. Call (877) 610-1318 for a free estimate with the full scope on paper.
Contact Barrett & Sons Construction for Your Bee Cave Home Addition or ADU
If you’re planning a home addition or ADU in Bee Cave, start with a lot survey and a written estimate – not a vague phone quote. Call (877) 610-1318 and Tom or one of his sons will walk you through what your 78738 lot can actually support, what the permit will require, and what the job will cost, all in writing. You’ll get a free estimate, a straight answer, and no pressure. If you have a written estimate from another contractor, bring it in for a free second opinion. We’ve been doing this since 1998, and we’ll be here to answer the phone when you call.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Bee Cave and the surrounding Hill Country since 1998.