







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Home Addition Contractor Across Alamo Heights
A home addition in Alamo Heights typically runs $180 – $420 per square foot depending on whether you’re adding a second story, a garage addition, or a bump-out. Most projects here take 10 – 16 weeks from permit to final inspection, with heritage tree reviews adding time when protected oaks sit near the footprint. If you’re planning a room addition, sunroom, or full second-story build in Alamo Heights, call (210) 981-6358 for a written price before any work starts.
We know Alamo Heights lots are different from what you’ll find ten minutes south. Large, tree-shaded properties with 1920s-era homes mean every addition has to respect what’s already there, from stucco matching on Jones-Maltsberger to drainage patterns near Olmos Creek. Our crews work these streets regularly and arrive with shoe covers, drop cloths, and a plan that accounts for your home’s age before the first tool comes out.
Why Seedling ADU San Antonio Is Alamo Heights’s Preferred Home Addition Contractor Company

Alamo Heights homeowners call us because we write the price down before work begins. That written quote covers materials, labor, permits, and the specifics of your lot, whether you’re off Broadway or tucked near Cambridge Oval. No line items appear after the crew starts. Our Home Addition Contractor team has built a local reputation on showing up when we say we will and leaving the house clean enough for a kid to crawl across the floor each evening.
Ben Ortega leads every Alamo Heights project. He walks each job before quoting, checks the tree survey, and reviews the architectural style the city expects. Our background-checked, uniformed technicians introduce themselves at the door, and a live person answers our phone 24/7 during an active build. That matters when you have questions at 8pm about tomorrow’s framing inspection.
Local knowledge here isn’t optional. We understand the 78209 permitting rhythm, the heritage tree ordinance, and what the Architectural Review Board tends to flag. That’s why Alamo Heights families keep referring us to their neighbors on Patterson and along Estes.
Second Story Addition Contractor in Alamo Heights
A Second Story Addition Contractor in Alamo Heights has to clear a higher bar than in most San Antonio neighborhoods, because the city requires wind-load calculations for any vertical addition, not just for new construction. A typical second-story addition in Alamo Heights runs $240 – $420 per square foot, with two bedrooms and a bath commonly landing between $180,000 and $310,000. The price reflects structural reinforcement to the existing first floor, stucco or siding that matches the original style, and engineering stamped for 110 mph wind exposure.
When a family has outgrown a 1930s cottage but loves the lot, going up often makes more sense than moving. We’ve helped homeowners off Patterson and Morton add master suites and kids’ bedrooms without touching the footprint of their existing foundation.
Wind-Load Engineering and City Review
Alamo Heights requires stamped wind-load calculations before a second-story permit is issued. A cheap quote that skips this step fails inspection, and re-engineering mid-project costs both money and weeks. Our quotes include the engineering letter and the calculations, so the first inspection is the only inspection.
Architectural Matching for Older Homes
Homes near the Alamo Heights border often carry Spanish Colonial or English cottage detailing that the Architectural Review Board expects to see respected. We match stucco texture, roofline pitch, and window sizing so the addition reads as original rather than bolted on.
Garage Addition Contractors in Alamo Heights

Garage Addition Contractors in Alamo Heights face a unique constraint: many of these lots were laid out before the two-car garage was standard, and the city’s heritage tree ordinance can add months to approval when a protected oak stands within ten feet of the proposed footprint. A detached two-car garage addition in Alamo Heights typically runs $55,000 – $110,000, depending on whether it includes a finished interior, electrical service, or a second-story suite above. Attached garage additions run slightly less, $45,000 – $90,000, since they share one existing wall.
On a shaded lot off Morton Street, our crew framed a garage addition with James Hardie fiber cement siding rated for 110 mph wind loads, common for Alamo Heights exposure. The permit review flagged a heritage oak 8 feet from the proposed footprint. We revised the foundation plan to pier-and-beam with root-bridge detailing and got approval without removing the tree. Inspections passed on first visit, and the homeowner’s insurer accepted our stamped wind-load certificate for a premium discount.
Heritage Oak Protection and Pier Foundations
When a protected tree sits near the build area, we use pier-and-beam foundations with root-bridge detailing instead of a full slab pour. This satisfies the city arborist, keeps the oak healthy, and often speeds up the permit once the revised plan is submitted.
Flood-Proofing Near Olmos Creek
Low-lying lots near Olmos Creek need drainage planning that a generic garage quote omits. We grade and add channel drains where needed, and we include flood-proofing details in the written price so there are no surprises during October downpours.
Trusted Brands We Service in Alamo Heights
We work with the brands serious Alamo Heights homeowners research before calling anyone: James Hardie fiber cement siding, Plant Prefab for modular additions, and Tuff Shed for permitted accessory structures. Because our San Antonio office stocks local material for these product lines, we can match existing exterior details on 1920s homes without waiting weeks on special orders. Scheduling and dispatch are coordinated from our San Antonio office, but the crews serving Alamo Heights work these streets daily.
Common Home Addition Contractor Problems We See in Alamo Heights Homes
- Wind-load calculations skipped on second-story quotes. A contractor eager to win the bid omits the engineering fee, then the framing fails the city inspection and the project stalls for re-engineering. We include the stamped calculations in every Alamo Heights quote, so the price you see is the price that passes.
- Tree surveys ignored until after the design is done. A protected oak within ten feet of the proposed footprint triggers an arborist review that can add months. We run the tree survey before we finalize any plan off Broadway or near Cambridge Oval.
- Stucco and siding that doesn’t match the original home. Alamo Heights is dense with Spanish Colonial and Mediterranean detailing, and the Architectural Review Board notices a mismatch. We match texture, color, and roofline so the addition belongs to the house.
- Drainage overlooked on low-lying lots. Heavy downpours pool near Olmos Creek and along some of the older streets, and an addition without proper grading channels water toward the foundation. We address drainage in the written price, not as a change order later.
Pricing for Home Addition Contractor in Alamo Heights, TX
A room addition in Alamo Heights runs $180 – $280 per square foot, a sunroom $35,000 – $80,000, a bathroom addition $45,000 – $90,000, and a bump-out between $30,000 and $60,000. Second-story additions land higher at $240 – $420 per square foot because of the structural work and wind-load engineering the city requires. Garage additions run $45,000 – $110,000 depending on size, finish level, and whether protected trees push you to a pier-and-beam foundation. Heritage oak reviews, architectural matching, and flood-proofing details all shape the final number. Call (210) 981-6358 for a free estimate. You’ll get a written price before any work starts.
We Also Serve Cities Near Alamo Heights
Our crews serve Home Addition Contractor in Alamo Heights and the surrounding communities, including San Antonio, New Braunfels, Selma, and Boerne. If you’re planning an addition anywhere in this part of Bexar County, call the same number, (210) 981-6358, and we’ll send someone out to walk the lot and write a real quote.
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 Home Addition Contractor in Alamo Heights
Alamo Heights requires second-story additions to be engineered for 110 mph wind loads, matching the exposure common across the area. The permit office wants stamped calculations from a licensed Texas engineer before framing begins. We include those calculations in every written quote, and our inspections pass on the first visit because the engineering is already in the plan. Call (210) 981-6358 for a free estimate that includes the wind-load documentation.
Yes, if a protected tree sits within ten feet of the proposed garage footprint, you’ll need an arborist review and a tree permit before the city approves the plan. This can add months to the approval timeline, which is why we run a tree survey before finalizing any Alamo Heights garage design. Our pier-and-beam foundation approach often satisfies the arborist without removing the tree. Call (210) 981-6358 and we’ll check your lot’s tree coverage before you commit to a plan.
A stamped wind-load certificate from a licensed engineer can qualify your Alamo Heights home for a premium discount with most major insurers. The letter proves the second-story framing meets the 110 mph standard, and insurers in this area accept it as documentation of reduced storm risk. We provide that letter after every second-story and garage addition passes final inspection, at no extra charge. Call (210) 981-6358 for a quote that includes the compliance documentation.
Alamo Heights requires additions to respect the existing home’s architectural character, especially for homes built between the 1920s and 1950s. The Architectural Review Board looks at stucco texture, roofline pitch, window proportions, and exterior materials. On Spanish Colonial and Mediterranean homes, that means matching clay tile or flat stucco profiles; on English cottages, it means keeping rooflines steep and windows divided. We match the existing home’s details in every Alamo Heights addition quote. Call (210) 981-6358 to schedule a free estimate for your project.
Yes, a garage addition with a second-story ADU above is one of the most common projects we quote in Alamo Heights. The combined structure typically runs $120,000 – $220,000, depending on square footage and the site conditions, including any heritage oak constraints. City zoning in Alamo Heights permits this configuration on many lots, and the wind-load engineering covers the whole structure, which simplifies both permits and insurance documentation. Call (210) 981-6358 and we’ll walk your lot, check the tree survey, and write a full price before anything starts.
Written by Ben Ortega, Owner at Seedling ADU San Antonio, serving Alamo Heights with written pricing and the 365-Day Done Right Promise.









