A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Room Addition Contractor Across Alamo Heights
A room addition in Alamo Heights typically runs $180 – $320 per square foot for site-built work, with garage conversions landing closer to $120 – $190 per square foot. Most projects here take 8 – 16 weeks from permit to final walkthrough, and the biggest cost driver is what we find when walls come open on a 1930s or 1940s house. If you’re planning an in-law suite, a home office, or a second-story addition near Broadway or along Burr Road, call us at (430) 258-2928 for a written, line-item price before any work starts.
Why Benson ADU San Antonio Is Alamo Heights’s Preferred Room Addition Contractor Company
We’ve worked on enough Spanish Colonials and Mediterranean stucco homes in Alamo Heights to know the difference between a quote that survives demolition and one that gets shredded the moment framing is exposed. Homeowners across Alamo Heights call us because we put the price in writing first, and because our Room Addition Contractor team walks the property, checks the lot coverage math, and flags code triggers before drawings are finalized. Troy Eastman leads our San Antonio-based crews, and every technician who arrives on a Alamo Heights job site is background-checked and in uniform.
Our reputation in Alamo Heights comes down to one habit: we don’t hide behind allowances that keep the door open for surprise invoices. The 365-Day Done Right Promise backs every project in writing. If something isn’t right within a full year, we make it right. And you’ll always reach a live person when you call, day or night.
In Law Suite Builders in Alamo Heights
In law suite builders in Alamo Heights handle a specific kind of room addition: a private, self-contained living space attached to or built within the existing home, usually with its own entrance, bathroom, and small kitchenette. On the smaller lots that dominate Alamo Heights, an in-law suite often replaces a garage conversion or tucks into a side yard that can’t fit a detached structure. Expect $150,000 – $260,000 for a permitted in-law suite here, depending on whether you’re converting existing square footage or adding new foundation.
Attached suites that respect the main house
Because Alamo Heights requires architectural compatibility with the primary structure, attached in-law suites usually mirror the roof pitch, stucco texture, and window proportions of the original home. We design additions that read as part of the house, not a box bolted onto it. This matters for both the design review board and future resale.
Garage conversions with private entrances
Many Alamo Heights homeowners with 1920s – 1950s garages choose a conversion over new construction. The slab is already there, the setbacks are already met, and the lot coverage math usually works in your favor. We handle the insulation, plumbing rough-ins, and the separate exterior door that turns a garage into a true in-law suite.
ADU Conversion in Alamo Heights
ADU conversion in Alamo Heights means transforming an existing structure, like a detached garage, pool house, or storage building, into a legal accessory dwelling unit rather than building from scratch. That distinction matters here because the city’s 40% maximum building coverage per lot rule often makes ground-up ADUs impossible, while conversions work within the footprint you already have. A garage-to-ADU conversion in Alamo Heights runs $110,000 – $190,000 depending on condition and finishes.
Working with your existing slab
Older Alamo Heights garages sit on slabs poured before modern moisture barriers existed. We test for slab integrity and vapor issues before framing, then quote any needed remediation as part of the written price. You’ll know before demo starts whether your slab is ready or needs underlayment work.
Design review compliance on conversions
Because Alamo Heights enforces its own zoning ordinance separate from San Antonio’s, every ADU conversion must be architecturally compatible with the main house. That means matching material language: stucco, clay tile, wood windows. We prepare design review submissions with finish schedules that satisfy the board without endless revision cycles.
Trusted Brands We Service in Alamo Heights
We build with systems from Abodu, Plant Prefab, and Tuff Shed, and we finish exteriors with James Hardie cladding where design review allows. Prefab panels from Abodu or Plant Prefab cut weeks off a Alamo Heights addition because walls arrive pre-built and get set in days, not weeks. For Alamo Heights homeowners, that means less time with a torn-up side yard and fewer weather delays during the hot, humid stretch from June through September. You can research every brand we use independently before you commit, and we’ll show you samples and spec sheets at the estimate.
Common Room Addition Contractor Problems We See in Alamo Heights Homes
- Knob-and-tube wiring behind original plaster. Houses built between the 1920s and 1950s in Alamo Heights often still carry original wiring. Opening a wall for an addition triggers an electrical upgrade to current code, and that cost needs to be in the contract before demo, not after.
- Failed waterproofing behind stucco. On a street near Broadway, our crew opened a 1930s Spanish Colonial for a second-story addition and found roof flashing that had been failing for years, letting water run behind the stucco. That kind of hidden rot changes the framing scope quickly.
- Termite and clay-soil framing damage. Alamo Heights sits on expansive clay that moves with moisture. Combined with decades of termite pressure, that leaves studs out of plumb and rim joists compromised. Any addition that ties into existing framing has to address those conditions first.
- Lot coverage surprises after drawings are done. The 40% building coverage limit in Alamo Heights catches homeowners off guard, especially on shaded lots near Broadway where mature oaks also restrict buildable area. We calculate coverage before design work begins so you don’t pay for drawings that can’t be permitted.
Pricing for Room Addition Contractor in Alamo Heights, TX
A room addition in Alamo Heights runs $180 – $320 per square foot for site-built work. At the lower end you’ll find simple bump-outs and garage conversions; at the upper end, second-story additions with structural reinforcement and full design review compliance. Expect $5,000 – $15,000 for architectural drawings and engineering, $2,000 – $6,000 for permit fees, and $8,000 – $25,000 in code-triggered electrical or plumbing upgrades on pre-1960 homes. We write allowances for every one of these line items into your contract, and no change order ever gets approved verbally. You sign a written change order and see the updated price before we touch anything. Call (430) 258-2928 and we’ll walk your property, check your lot coverage, and hand you a written estimate.
We Also Serve Cities Near Alamo Heights
Our crews work throughout the Alamo Heights area and into nearby communities including San Antonio, Schertz, Live Oak, and Leon Valley. If you’re outside the Alamo Heights city limits but still need a room addition priced honestly, we’ll schedule a site visit and give you the same written estimate. Each project follows the same process: inspection first, allowances in writing, and no surprise invoices.
Serving Alamo Heights, TX - Our Local Coverage Area
We’re based in the Alamo Heights 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 Room Addition Contractor in Alamo Heights
Yes, likely. Alamo Heights caps building coverage at 40% of your lot, and once your addition pushes past that threshold, you’ll need a variance hearing before the city will issue permits. We run the coverage math during the first site visit, before any drawings are commissioned, so you know exactly what you’re facing and what a variance will add to your timeline and budget. Call (430) 258-2928 and we’ll check your lot against city records.
Expect electrical upgrades first, especially if we find original knob-and-tube wiring. The city will require that any newly opened wall cavity meet current code for wiring, insulation, and framing connections. On a 1940s Alamo Heights home, that often means replacing the service panel, adding arc-fault breakers, and bringing wall insulation up to current R-value standards. We write those allowances into the contract before demolition so the permit process doesn’t become a series of financial surprises.
We match the existing stucco texture, roof tile profile, and window proportions from the start. Our team photographs and samples the existing facade, then specifies finishes that meet design review before the drawings are submitted. That means when the board looks at your plans, the addition already reads as part of the original house, not a bolted-on afterthought. A recent second-story addition on a 1930s Spanish Colonial near Broadway passed review precisely because the new deep-red tile roof tied into the existing clay profile.
Usually yes. A ground-up addition on a small Alamo Heights lot has to fit within the remaining buildable area after the 40% coverage cap, plus tree protection zones around mature oaks which further shrink usable footprint. A garage conversion works within the existing slab and footprint, so it sidesteps both the coverage calculation and most tree protection conflicts. On the lots near Broadway where oaks dominate, we typically recommend conversion first and ground-up only if the garage isn’t structurally sound.
We stop, document it with photos, and hand you a written change order with a firm price to repair the waterproofing before we continue framing. We don’t ask for a verbal approval and send the bill later. On the 1930s Spanish Colonial near Broadway I mentioned earlier, the failing roof flashing had been letting water run behind the stucco for years. We wrote the repair into the contract before demo started, so the only surprise was how cleanly the new work tied into the old clay tile. Call (430) 258-2928 to get your addition priced the same way.
Written by Troy Eastman, Owner at Benson ADU San Antonio, serving Alamo Heights with written pricing and the 365-Day Done Right Promise.
