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
Adding square footage to a home in Alamo Heights means working inside a special set of rules. Benson ADU San Antonio handles home additions here every week, and we start every project the same way: a written inspection, a written price, and a line-item plan for the surprises these 1920s-to-1950s homes tend to hide. If you’re planning a room addition, second story, sunroom, bathroom, garage, or bump-out in Alamo Heights, call (430) 258-2928 to get a free estimate from our Home Addition Contractor team. No verbal ballparks that drift later. A real number, in writing, before we open a single wall.
Key Takeaways for Alamo Heights Homeowners
- Alamo Heights has its own zoning code with a 40% maximum building coverage rule. Even small additions often need a variance and design review.
- Homes here date mostly from the 1920s through the 1950s. Expect knob-and-tube wiring, undersized old framing, or failed stucco waterproofing once walls open.
- A bathroom addition in Alamo Heights typically runs $45,000 to $95,000 depending on scope and hidden conditions. A garage addition usually falls between $55,000 and $110,000.
- Our written price includes allowances for the things inspection will likely trigger, so change orders are priced and approved before any work happens.
- Every project carries the 365-Day Done Right Promise, in writing, stamped on your contract.
Why Benson ADU San Antonio Is Alamo Heights’s Preferred Home Addition Company
We know the difference between building in Alamo Heights and building a mile away in San Antonio. It is not the same rulebook. Alamo Heights enforces its own zoning ordinance, its own architectural compatibility requirements, and its own review process. That changes how we bid a project here: before we quote an attached addition on a tree-shaded lot near Broadway, we look at the main house’s roofline, window patterns, and exterior materials, because the city will ask us to match them. Most contractors skip that step and find out later. We do it first.
Troy Eastman leads our team, and he has built enough additions in Alamo Heights to know the city wants Spanish Colonial additions to look Spanish Colonial, not like a prefab box bolted to a 1930s stucco wall. That does not mean you cannot build with modern prefab panels from Plant Prefab or use James Hardie cladding. It means the exterior detailing, roof pitch, and window proportions have to fit the main house. When we can show the design review board a plan that already matches their compatibility rules, your variance moves faster and costs less.
Our crews are background-checked, uniformed, and scheduled with a live arrival time you will actually get. A live person answers our phone around the clock, every day of the year. If you call about an addition in Alamo Heights at 9 p.m., you will talk to a person, not a voicemail loop. That matters when you are trying to plan a bathroom addition around a family schedule and need a straight answer about when we can start.
Garage Addition Contractors in Alamo Heights
Garage Addition Contractors in Alamo Heights face a specific challenge most of the city’s homes share: the lots are small, deep-set, and already close to the 40% building coverage limit. That pushes many Alamo Heights homeowners toward attached garage additions that tuck into an existing side wall rather than detached structures that eat up yard space. We build both, but on lots near Broadway where the setbacks leave maybe eight feet of side yard, an attached garage addition with a matched roof pitch is usually the only plan that clears design review without a long variance fight.
Costs for a garage addition in Alamo Heights typically land between $55,000 and $110,000. A simple single-car attached addition with no living space above runs toward the lower end. Adding a second story, a workshop, or a finished room above the garage pushes the number up quickly. Every quote we give includes line-item allowances for what we might find once we open the wall, because a 1940s garage wall that meets a 2026 addition is very likely hiding old wiring or a footing that has not aged gracefully in the local clay soil.
What Affects the Garage Addition Price
The biggest cost swings come from foundation work, electrical service capacity, and roof framing. Alamo Heights clay soil expands and contracts with moisture, so we spend money on proper footings and drainage at the start rather than chasing cracks later. If your existing panel is full or the service is still 100-amp, code will require an upgrade before we can feed the new garage circuits. We write those allowances into the contract so the price you approve is the price you pay.
Garage Addition Timeline and Permits
We pull every permit and schedule every inspection for you. Alamo Heights design review runs separately from the building permit, and the review board meets on a set schedule, so the timeline includes that review period plus the structural plan review. Once we have approvals, a single-car attached garage addition in Alamo Heights typically takes nine to fourteen weeks from first excavation to final inspection. Larger structures with a room above run longer.
Bathroom Addition Contractor in Alamo Heights
A Bathroom Addition Contractor in Alamo Heights works on homes that were framed, wired, and waterproofed long before modern code existed. On a tree-shaded street near Broadway, we opened the exterior wall of a 1940s Mediterranean main house to tie in a new bathroom addition and found original knob-and-tube wiring feeding a load-bearing stucco corner that had failed waterproofing. Our techs rewired the affected circuits to current NEC, sistered the undersized 2×4 studs, installed peel-and-stick membrane before recladding, and documented every change-order line item for the city inspector. That is what a real bathroom addition here looks like under the surface.
What does that mean for your budget? A bathroom addition in Alamo Heights typically runs $45,000 to $95,000. A modest full bath added off a hallway falls toward the lower end. A primary suite bathroom with a double vanity, walk-in shower, and a new roofline to match a Spanish Colonial main house moves toward the top. The variance here is mostly about what is hiding inside the wall and how much compatibility work the design review board asks for.
Code Upgrades That Come With the Permit
Once we open walls for a bathroom addition, the permit triggers a chain of required upgrades. Knob-and-tube wiring feeding the area must be replaced or disconnected. Any undersized joists or studs in the new wet wall get sistered or rebuilt. Ventilation must meet current CFM requirements, and the waterproofing system behind tile has to meet today’s standards, not 1948’s. We build those items into the initial quote as allowances, because they are not optional surprises. They are code.
Waterproofing Older Stucco and Masonry
Alamo Heights homes have tile roofs and stucco or masonry exteriors that were never designed to shed water into a new bathroom wall. When we tie a new addition into an old exterior wall, we address the waterproofing at the transition before we close anything up. Peel-and-stick membrane, properly lapped flashing, and a drainage plane behind the new cladding keep the hot, humid Alamo Heights summers and occasional heavy rain events from turning your new bathroom into a moisture problem in eighteen months.
Trusted Brands We Service in Alamo Heights
We build with product lines Alamo Heights homeowners can research independently. Our work with Plant Prefab and Abodu lets us offer a curated set of panelized options that speed up framing and reduce weather exposure during the build. For cladding and exterior detailing that has to satisfy design review, James Hardie materials give us the ability to match stucco and masonry textures while meeting the city’s architectural compatibility requirements. We also build with Tuff Shed structures for simple attached storage and workshop additions that need to clear Alamo Heights design review quickly. Because we keep these relationships active, Alamo Heights customers get real options instead of one take-it-or-leave-it product, with lead times we can actually quote.
Common Home Addition Problems We See in Alamo Heights Homes
- Clay soil movement under old footings. The local clay expands when wet and contracts when dry, which is exactly what it has been doing under your 1930s house for ninety years. Opening a wall for an addition without checking the footing first is how a small bump-out becomes a full foundation repair.
- Knob-and-tube wiring behind old plaster and lath. Homes built before about 1950 often still carry original wiring in hidden wall cavities. Once the permit inspection sees it, replacement is mandatory. We allow for this in the quote rather than treating it like a surprise.
- Undersized 2×4 framing from the 1920s and 1930s. Old framing was often notched, sistered poorly, or just dimensionally small by modern code standards. We document what the wall actually carries before we cut a new opening, then price the reinforcement up front.
- Failed stucco waterproofing where old exterior meets new addition. The original stucco on a 1930s Alamo Heights home was never detailed to tie into a new roof or wall system. The fix is membrane, flashing, and drainage details at the transition, done before recladding so moisture cannot track inside.
Pricing for Home Addition Contractor in Alamo Heights, TX
We publish ranges because Alamo Heights homeowners deserve a ballpark before they ever tap call. A garage addition here runs $55,000 to $110,000. A bathroom addition runs $45,000 to $95,000. A modest bump-out for a kitchen or living space typically runs $65,000 to $140,000 once you account for foundation, framing, roofing, electrical, and the design review process. Second story additions start around $150,000 and climb with the complexity of matching an existing Mediterranean or Spanish Colonial roofline. These are real numbers, not teaser quotes. Your written estimate includes line-item allowances for code triggers we know Alamo Heights inspectors will call out. Call (430) 258-2928 to schedule your free estimate. The number you approve is the number you pay, and any change order gets priced and signed before we touch the work.
We Also Serve Cities Near Alamo Heights
Our crews work throughout the surrounding area, including San Antonio, Schertz, Live Oak, and Leon Valley. Each city has its own rules, but the process stays the same: written price first, real-time tracking, and the 365-Day Done Right Promise on every project. If you are planning an addition just outside Alamo Heights, call (430) 258-2928 and we will tell you straight what applies to your lot.
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
You should expect the permit to trigger electrical, structural, ventilation, and waterproofing upgrades. Original knob-and-tube wiring in the wall must be replaced or disconnected, undersized framing in load-bearing sections has to be reinforced, and the new bathroom must meet current ventilation CFM and waterproofing standards. We write these allowances into the initial quote so they are not surprise costs. Call (430) 258-2928 and we will walk you through exactly what a bathroom addition on your specific floor plan will likely require.
We price it with a written allowance in the contract, not a blank check. Before we quote, we do a structural site visit to assess the existing framing, foundation, and roof condition where the new addition will tie in. Then we write a line-item allowance for reinforcement work, with a stated process: if we open the wall and the condition is better than allowed, you get the difference back. If it is worse, we price the additional work in writing and get your approval before any further demolition. Call (430) 258-2928 for an exact quote on your addition.
Most likely yes, because Alamo Heights caps building coverage at 40% of the lot and many of the smaller lots near Broadway are already close to that number with just the main house. An attached addition that pushes total coverage past the limit requires a variance and design review. We prepare the variance package, including drawings that show architectural compatibility with the existing home, and we handle the submittal for you. Call (430) 258-2928 to find out whether your specific lot triggers a variance or only design review.
The transition is the hard part. A newer home has a continuous water-resistive barrier and modern flashing details, so tying a new addition into an existing exterior wall is straightforward. A 1920s Alamo Heights home has stucco directly over old framing with no drainage plane, and the original flashing details were not designed to receive a new roof or wall intersection. We install peel-and-stick membrane at the transition, lap new flashing over old, and create a drainage path behind the new cladding so water from Alamo Heights’s heavy rain events exits rather than collecting inside the wall. Call (430) 258-2928 for a written waterproofing plan on your addition.
We handle everything we are allowed to handle. For a garage addition in Alamo Heights, that includes the building permit, the design review, the variance if required, and preparing the submittal package with drawings and material specifications. If your property falls under an HOA or a neighborhood association with its own architectural review, we prepare the same package for their review board and coordinate the submittal. You will not have to chase an inspector or a reviewer, and every approval gets documented in your project file. Call (430) 258-2928 to start your garage addition estimate today.
Call Benson ADU San Antonio for Your Alamo Heights Addition
If you are planning a room addition, second story, sunroom, bathroom addition, garage addition, or bump-out in Alamo Heights, the first step is a written inspection and a real number. We will look at your lot coverage, your roof and foundation, your existing wiring, and your design review risk. Then we will put a price in writing, with allowances for what these older homes hide. Call (430) 258-2928 to schedule your free estimate. A live person answers, day or night.
Written by Troy Eastman, Owner at Benson ADU San Antonio, serving Alamo Heights and surrounding communities.
