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Before
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Before
AfterNew Construction in San Antonio, TX
New construction roofing in San Antonio means installing a complete roof system on a brand-new home, addition, or detached structure, from bare decking up. Most full new-construction roof installations on a single-family home here run between $12,000 and $28,000 depending on square footage, shingle grade, roof pitch, and the number of penetrations like vent stacks and skylights. Mercer Roofing Co San Antonio handles the entire process: underlayment, flashing, shingles, ridge ventilation, and written workmanship coverage on every job. If you’re building new or adding on, call (254) 276-4369 and we’ll walk you through what your specific roof will cost before any commitment. For a broader look at what full roof work involves, see our Roof Replacement & Installation page.
When You Need New Construction
New construction roofing isn’t repair work. It’s starting from a clean deck and building the entire roof system correctly the first time. Here are the situations where that applies in San Antonio:
- You’re building a new home. Whether you’re working with a general contractor or acting as your own builder, the roof has to be installed in sequence with framing, electrical, and plumbing rough-ins. We coordinate directly with your GC so the roof goes on when the deck is ready.
- You’re adding a room or a second story. A room addition in neighborhoods like Alamo Heights, Stone Oak, or Terrell Hills means tying new roof framing into the existing structure. If the tie-in is done wrong, you’ll get leaks at the seam within the first two years. We’ve seen this repeatedly on additions built in the 1990s and early 2000s around the North Side.
- You’re building a detached garage, workshop, or casita. Backyard structures still need a real roof system: decking, underlayment, drip edge, and proper ventilation. A detached garage in areas like King William or Monte Vista with a simple gable roof typically runs $6,000 to $11,000 for a full new-construction roof.
- Your builder’s roofing sub walked off the job or cut corners. It happens more than people admit. We’ve been called to subdivisions in Cibolo, Helotes, and the Far West Side where a builder-grade roof was slapped on with missing starter strip, reused flashing, or no ice-and-water shield in valley areas. If you’re looking at bare decking or a half-finished roof, we can step in and finish it right.
- Storm damage on a brand-new build left you with no roof at all. A hailstorm or wind event can tear off a new roof before the home is closed on. When that happens, the builder’s warranty often doesn’t cover it because the home hasn’t transferred yet. We handle those claims directly with your insurance carrier.
Our New Construction Process
New construction roofing has a specific sequence. Skip a step and the roof fails early. Here’s exactly how we handle it:
- Deck inspection and prep. Before any material goes down, we check that the OSB or plywood decking is clean, dry, properly fastened, and free of gaps over 1/8 inch. We also verify that the framing will carry the roof load. If decking is substandard, we say so before we proceed.
- Underlayment and ice-and-water shield. San Antonio gets intense sun and occasional torrential rain. We install a full synthetic underlayment across the deck, plus self-adhered ice-and-water shield in valleys, around penetrations, and along eaves. This is the layer that keeps wind-driven rain out of your attic.
- Flashing and drip edge installation. Every chimney, skylight, vent pipe, wall intersection, and valley gets metal flashing installed before shingles go on. Drip edge goes around the entire perimeter. Flashing is where most new-construction roofs fail, so we spend extra time here.
- Shingle installation to manufacturer spec. We install your chosen shingle system, usually Owens Corning, GAF, or CertainTeed, exactly to the manufacturer’s published installation spec. That matters because the shingle warranty only holds if the installation method matches the spec sheet.
- Ridge ventilation and final inspection. We install ridge vent or box vents sized to your attic’s square footage, then do a full walk-through with you or your GC. Every nail, every seam, every flashing point gets checked before we call the job complete.
New Construction Pricing in San Antonio
Here’s what new-construction roofing costs in the San Antonio market today, based on the jobs we quote regularly:
- Detached garage or workshop (400-600 sq ft of roof): $6,000 to $11,000
- Room addition (300-800 sq ft of roof): $5,500 to $12,000
- Full new single-family home (2,000-3,500 sq ft of roof): $12,000 to $28,000
- Full new home with high-end shingle (CertainTeed Grand Manor, Owens Corning Duration Designer): $18,000 to $35,000
- Full new home with steep pitch, complex valleys, or standing-seam metal accents: $22,000 to $40,000+
What moves the price:
- Roof pitch. A 4/12 roof is fast and safe to walk. An 8/12 or higher on a custom build in Terrell Hills or the Dominion requires staging and harness work, which adds labor cost.
- Number of penetrations. Every vent stack, plumbing boot, skylight, and chimney means more flashing and more time. A simple gable roof with two vent pipes is cheap. A cut-up roof with six valleys, three skylights, and two chimneys is not.
- Shingle grade. Standard architectural shingles from Owens Corning or GAF run $4.50 to $6.50 per square foot installed in San Antonio. Premium designer shingles run $7 to $12 per square foot installed.
- Decking condition. If we’re roofing an addition where the framer already laid decking, we may need to re-nail or replace sheets. That’s typically $2 to $4 per square foot of decking replaced.
- Access. Homes on tight lots in King William or Lavaca often require hand-carrying shingles from the street. Homes with a long driveway in Fair Oaks Ranch need more crane or boom time. Both add cost.
Every new-construction estimate from Mercer Roofing Co San Antonio includes a written price before any work starts. The price you see on the estimate is the price on the invoice. No allowances that balloon later, no change orders unless you change the scope. Call (254) 276-4369 and we’ll get you a free, written estimate for your new build.
FAQs – New Construction
How much does new construction roofing cost in San Antonio?
New construction roofing in San Antonio typically costs between $12,000 and $28,000 for a full single-family home, $5,500 to $12,000 for a room addition, and $6,000 to $11,000 for a detached garage or workshop. The biggest cost drivers are roof square footage, pitch, shingle grade, and the number of penetrations that need flashing. Call (254) 276-4369 for a free written estimate specific to your project.
Can you start on my new roof right away?
In most cases, we can schedule new-construction roofing within one to three weeks, depending on current demand and weather. During the spring hailstorm season in San Antonio, scheduling tightens because of storm repair volume. If your builder is waiting on the roof to pass inspection, tell us that when you call and we’ll do our best to accommodate the timeline. Call (254) 276-4369 to check current availability.
Is it cheaper to roof new construction than to replace an existing roof?
Yes, usually by 15 to 20 percent. New construction roofing skips the tear-off, dump fees, and deck repair that a replacement requires. On a 2,500 square foot roof in San Antonio, that tear-off and disposal can run $2,500 to $4,500 on its own. If you’re building new, you’re starting from a clean deck, and that savings is real.
What shingle brands do you install on new construction?
We install shingles from GAF, CertainTeed, Owens Corning, and Boral, among others. For most new-construction homes in San Antonio, we recommend a Class 3 or Class 4 impact-rated architectural shingle from GAF or Owens Corning. These hold up better to the hail we see across the Hill Country and often earn you a discount on homeowners insurance. We’ll match the shingle to your budget and the home’s architecture, and the written estimate will name the exact shingle line.
Do you work with builders and general contractors?
Yes. We work directly with builders, general contractors, and homeowners acting as their own GC across San Antonio, including projects in Stone Oak, Alamo Ranch, Fair Oaks Ranch, and the surrounding Hill Country. If you’re a builder, we’ll coordinate scheduling, provide the documentation your inspector needs, and make sure the roof passes the first time. Call (254) 276-4369 and ask for Grant.
What You Get With Mercer Roofing Co San Antonio
We started Mercer Roofing in 2000, and the thing that still sets us apart is simple: you know exactly who is coming to your home before they arrive. Every technician we send is background-checked, identity-verified, and held to the Threshold Verified standard. You get their name and photo sent to you ahead of the visit. When they arrive, they present a photo ID badge at the door, in a clean, marked uniform. No strangers, no surprises.
Our 365-Day Done Right Promise covers every new-construction roof we install. If something isn’t done right within a year, we make it right. Every job also includes a written guarantee. And when you call Mercer Roofing, a live person answers the phone. Not a voicemail, not a call-back form. A real human, 24/7.
Grant Whitlock leads our San Antonio team. He’s the person you’ll talk to about your new-construction roof, and he’s the one who makes sure the job is done to the standard we’ve held since 2000. If you’re building a home, adding on, or finishing a structure in San Antonio, call (254) 276-4369 for a free written estimate. We’ll tell you what it costs, we’ll tell you who’s coming, and we’ll put it all in writing before the first nail goes in.
Written by Grant Whitlock, Owner at Mercer Roofing Co San Antonio, serving San Antonio.