Home Additions in Bee Cave, TX: 2026 Costs & Process

What an addition costs in Bee Cave, and what moves the number

Additions are priced by square foot plus the cost of connecting new space to an existing house. The connection is where budgets move. A bump-out off an existing slab with no plumbing is a different animal from a second story that needs new footings, a new stair, and an upsized HVAC system.

Here is how we see Bee Cave projects group up. Every figure below is a typical range, and we replace it with one fixed number in your contract once the drawings are done.

Where a kitchen or bathroom falls inside the new space, our published Austin ranges apply inside the addition too: $45k–$70k for a kitchen in its existing footprint with new cabinets, counters, lighting and fixtures, $70k–$110k when the layout opens up and plumbing moves, and $110k+ for a high-end kitchen taken to the studs with custom cabinetry and high-end appliances.

• Bump-out, 80–200 sq ft (breakfast nook, closet, bath expansion): $70,000–$170,000
• Single-room ground-floor addition, 300–500 sq ft: $120,000–$290,000
• Primary suite addition with full bath, 450–700 sq ft: $220,000–$420,000
• Second-story addition, 700–1,200 sq ft: $300,000–$650,000+
• Drives cost up: new foundation on a sloped or rock lot, long plumbing runs, a new or upsized HVAC zone, upgraded electrical service, standing-seam metal roof, stone veneer to match the existing elevation, steel in the structural design, custom windows
• Drives cost down: building off the back of the house on flat ground, keeping wet rooms near existing plumbing, a roofline that extends the existing one instead of tying into it at a new pitch, stock window sizes, simple rectangles

What is particular about adding on in Bee Cave

Bee Cave sits in the Hill Country west of Austin, and the ground tells you most of what the foundation will cost. Limestone and shallow rock are common out here, so excavation for piers or a new slab can mean rock removal rather than a dirt dig. That is a line item we price after the geotechnical and structural drawings exist, not before — guessing at it is how homeowners end up with change orders.

Lots in this area are often sloped. A back-of-house addition that would sit flat in central Austin may need stepped footings, a retaining element or a pier-and-beam section in Bee Cave. A licensed structural engineer designs that, and the permit office reviews it. The same goes for any wall you are hoping to remove to open the old house into the new space — the engineer specifies what happens there and the reviewing authority signs off on it. We do not make that call on a site visit, and you should be wary of anyone who does.

Much of the housing stock around Bee Cave is newer than Austin's core neighborhoods, which usually works in your favor: modern framing, modern wiring, and a roof structure that is straightforward to tie into. It also means your exterior has a specific look — stucco, limestone veneer, a particular shingle or metal profile — and matching it matters more than it does on a 1950s bungalow. We budget for matching materials up front rather than treating it as a surprise at the end.

Finally, many Bee Cave neighborhoods have an HOA with architectural review. That review runs in parallel with permitting and can add two to six weeks before a shovel moves. Start it early; we will prepare the elevations and site plan the committee asks for.

Permits and inspections for a Bee Cave addition

An addition is a permitted project. Whether your property is reviewed by the City of Bee Cave, Travis County, or the City of Austin depends on where your address sits and which utility and development authorities apply to your lot. We confirm the reviewing jurisdiction before we price the job, and we handle the submittal, the plan review comments and the inspection scheduling as part of the contract. You should not be driving plans downtown.

Permit and review fees for a residential addition typically run $1,500–$5,000 depending on the jurisdiction, the square footage and whether a site or drainage plan is required. Engineering and survey costs are separate; expect $1,500–$4,000 for a structural engineer's drawings and $600–$1,500 for a current survey if you do not have one. All of it is itemized in your fixed-price contract so you are not discovering it later.

Impervious cover is the thing that trips people up on Hill Country lots. Adding roof area and any new driveway or patio counts toward the total your lot is allowed, and that is determined by the reviewing authority against your platted lot — not by a rule of thumb. We flag it during design so the footprint we draw is the footprint that gets approved.

Inspections happen in sequence during construction, roughly: foundation and reinforcement before concrete, framing, then rough plumbing, electrical and mechanical, then insulation, then a final. Each one has to pass before the next trade closes up the work. We coordinate them so the schedule does not stall waiting on a slot.

• We confirm which office reviews your address before pricing
• We prepare and submit the drawings, site plan and engineering
• We respond to plan review comments
• We schedule and meet every inspection
• Permit and review fees typically run $1,500–$5,000 and appear as a line item in your contract

Realistic timeline, first visit to final walkthrough

Additions take longer than people expect, and most of the extra time is before demolition. Design and permitting happen first so the construction calendar we hand you is the one we build to. Here is a realistic week count for a Bee Cave addition.

Total: roughly 28 to 52 weeks from first visit to final walkthrough for a typical room addition, and longer for a second story. If your addition includes a kitchen or a bathroom, those fit inside the construction phase at our usual pace — a bathroom is typically 3 to 5 weeks and a kitchen 6 to 10 weeks. A whole-home renovation combined with an addition runs 4 to 8 months of construction.

We do not promise a start date at the first meeting. We give you one once the permit is issued, because that is the first moment it is honest.

• Weeks 1–2: site visit, measure, scope conversation, budget range
• Weeks 2–8: design development, selections, structural engineering, survey
• Weeks 6–10: fixed price finalized and contract signed
• Weeks 8–20: permit submittal, plan review and HOA architectural review (varies by jurisdiction and by committee)
• Weeks 1–3 of construction: site protection, demolition, excavation
• Weeks 3–8: foundation, framing, roof dry-in
• Weeks 8–14: rough plumbing, electrical, mechanical, inspections, insulation, drywall
• Weeks 14–22: trim, cabinetry, tile, paint, flooring, fixtures
• Final 1–2 weeks: exterior tie-in, punch list, final inspection, walkthrough

How our fixed-price design-build process works

Design-build means one contract covers the drawings, the engineering coordination, the permitting and the construction. You are not managing a handoff between an architect and a builder, and nobody gets to blame the other one when something does not line up in the field.

We price the job after the drawings and selections are done, not before. That is why the number holds. A fixed-price contract lists the scope, the allowances, the schedule and the payment milestones. The only way the price changes is if you change the scope or the permit office requires something the drawings did not anticipate — and either way you approve it in writing before we proceed.

Our carpenters are in-house. On an addition that matters, because framing, trim and cabinetry installation are where the quality of the tie-in shows. Workmanship carries a 5-year warranty. Financing is available if you would rather not fund the whole build from cash or a HELOC.

Here is what to ask any contractor you interview in Bee Cave, including us.

• Is the price fixed in writing, or is it an estimate that can move?
• Who is submitting the permit and attending the inspections?
• Which licensed engineer is doing the structural drawings, and when?
• Are framing and trim crews employees or subcontracted?
• What are the allowances for tile, cabinetry, windows and fixtures, and what happens if I exceed them?
• What is the written workmanship warranty, and what does it exclude?
• How will you match the existing stucco, stone and roof?
• What is the payment schedule tied to — dates or completed milestones?

What to do next

Before you call anyone, gather three things: a copy of your survey if you have one, your HOA's architectural guidelines, and a rough list of what the new space has to do — bedrooms, bath, kitchen, office, all of it. That is enough for a useful first conversation about budget.

Then book a site visit. We will walk the lot, look at the slope and the existing roofline, talk through where an addition can reasonably go, and give you a range before you have spent anything on drawings. If the range works for you, we move into design, and the fixed price follows from there.

If you are weighing an addition against converting a garage or building an ADU, say so at the first visit. On some Bee Cave lots the impervious cover math makes one of those options cleaner than the other, and it is better to find that out in week one than in month four.

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