Commercial Roofing in Austin: How to Choose the Right System for Your Building
The right commercial roof for an Austin building depends on three things: how much slope the roof has, what's under it (cooled offices, a warehouse, a shop), and the condition of the roof that's there now. Most low-slope buildings here end up with a single-ply membrane like TPO, a modified bitumen roof, or metal. Sometimes a coating buys time on a roof that's still sound.
Here's how Vantage Roofing walks a building owner through that choice.
What are the main commercial roof systems in Austin?
Most commercial roofs in Central Texas fall into a few families:
TPO and other single-ply membranes. Wide sheets of light-colored membrane, heat-welded at the seams. Common on offices, retail centers, and flat-roof additions.
Modified bitumen and built-up roofs. Layered asphalt-based roofs, often with a granule or gravel surface. You'll see them on older strip centers.
Standing seam metal. Panels joined with raised seams and held by hidden clips that let the metal move as it heats and cools.
Through-fastened metal (often R-panel). Ribbed panels screwed straight through to the framing, with a rubber washer under each screw. Common on shops and warehouses.
Roof coatings. A liquid-applied layer over a roof that's still dry and solid. A coating extends a sound roof. It doesn't fix a failing one.
How does roof slope change your options?
Vantage Roofing measures slope first, because the building code sets a minimum for each system. The International Building Code calls for at least 1/4 inch of fall per foot for single-ply membranes like TPO, and the same for modified bitumen and built-up roofs.
Metal has its own rules. Standing seam panels can go down to that same 1/4-inch slope. Through-fastened panels with plain overlapping seams need a 3-in-12 slope, or 1/2-in-12 with lap sealant at the seams. That's why a screw-down panel that works on a pitched shop roof can leak on a nearly flat one.
Standing water matters too. The National Roofing Contractors Association calls it ponding when water is still there more than 48 hours after rain. Ponding means a drainage problem, and a new roof should fix it, not just cover it.
What do Austin's permit and energy rules mean for a new roof?
The City of Austin lists re-roofing under its commercial "Exterior Updates" permit, which covers work that doesn't enlarge the building or raise it more than six feet. Round Rock, Pflugerville, and other nearby cities have their own rules, so the building's address decides which office you deal with.
Austin also enforces the 2024 International Energy Conservation Code with local amendments, in effect since July 10, 2025. For low-slope roofs over cooled space, it requires a reflective "cool roof" surface that meets set reflectance values. A white membrane or a reflective coating is usually how that's met. A dark roof over an air-conditioned office may not pass.
Repairs get a break. Under Austin's amendments, repairs covering less than half the roof or less than 2,000 square feet (whichever is smaller) don't trigger the reflectance rule. So a patch stays a patch, but a full re-roof has to meet today's code. Vantage Roofing will tell you during the inspection whether your job needs a permit.
Can a new roof go over the old one?
Sometimes. Going over the old roof is called a recover, and the International Building Code limits it. A recover isn't allowed when:
The existing roof is water-soaked or too deteriorated to be a solid base.
The existing roof is slate, clay, or cement tile.
The building already has two or more roof coverings.
Wet insulation under a membrane can feel fine underfoot while it holds water and rots the deck. That's why Vantage Roofing checks for trapped moisture before recommending a recover.
Metal buildings have one more option. The code allows a standing seam system that carries its own loads to the structure to go over the old roof without a tear-off. The Insurance Institute for Business & Home Safety also describes building a new sloped metal roof over an existing flat roof with light steel framing. Either way, a structural engineer has to confirm the building can carry it.
How does hail affect a commercial roof in Central Texas?
Hail is a real factor here. NOAA's Storm Events Database lists 104 reports of one-inch or larger hail in Travis County since 2021 and 146 in Williamson County. On September 24, 2023, 4-inch hail fell in Round Rock.
Systems take hail differently. On metal, small dents are often cosmetic. IBHS notes that once the paint is cracked or flaked, the panel can corrode, and refinishing or replacement should be considered. On membranes, we look for punctures, cracked seams, and crushed insulation underneath. After a storm, Vantage Roofing helps owners document storm damage with photos for their insurance company.
What does a commercial roof inspection check?
A good inspection follows the water from the roof edge to the drains. On a typical Austin building, Vantage Roofing checks:
Drains, scuppers, and gutters. Clogged drains are behind a lot of commercial leaks.
Seams and laps. Open TPO welds, split laps, and loose metal seams.
Screws on metal roofs. Backed-out screws and cracked washers. Over- or under-tightening ruins the washer.
Penetrations and curbs. Pipes, vents, skylights, and HVAC curbs. Sealant here dries out in the Texas sun and should be checked about once a year.
Edges and corners. Wind damage usually starts there and works inward.
AC condensate lines. Lines that drain onto metal panels can corrode them over time.
Repair, restore, or replace: how do we decide?
Many commercial leaks turn out to be a repair: an open seam, a cracked pipe boot, or loose screws on a metal roof. If the rest of the roof is dry and solid, a targeted repair is the right call.
A coating or recover makes sense when the roof is mostly dry and the problem is age and wear, not water damage. A full replacement makes sense when large areas are wet, the roof leaks in many places, or there are already two roofs on the building. And sometimes the answer is nothing. If a stain comes from plumbing or an AC line, we'll tell you so you call the right trade.
The Asphalt Roofing Manufacturers Association recommends a professional inspection each spring and fall, and a simple file with the roof's install date, type, contractor, and repairs. That file makes every later decision easier.
Schedule a commercial roof inspection
Call (737) 383-1768 to schedule a free roof inspection for your commercial building in Austin, Round Rock, or nearby. We'll check the roof, show you photos, and tell you honestly whether it needs a repair, a replacement, or nothing at all. Vantage Roofing backs its work with a 10-year workmanship warranty on full replacements and up to 1 year on service repairs. You can also reach us through our contact page, read about commercial flat roofing, or see our guide to metal roof repair.
Frequently asked questions
Can you come look at it first before telling me what system I need?
Yes. That's where every commercial job should start. Vantage Roofing comes out for a free roof inspection, measures the slope, checks the drains, seams, and penetrations, and photographs what we find. Then we explain whether the building fits a membrane, metal, a coating, or just a repair. You get a written estimate after we've seen the roof.
Is TPO or metal better for a commercial building in Austin?
It depends on the building. TPO works well on flat and nearly flat roofs over offices and retail space, and its light surface helps meet Austin's cool-roof rule. Standing seam metal suits low-slope roofs on shops, warehouses, and metal buildings. The roof's slope, what's under it, and how the current roof is built usually point to the right choice.
Can you put a new roof over my old commercial roof?
Sometimes. The building code allows a recover when the existing roof is dry and solid and there's only one roof on the building. If the old roof is water-soaked, badly deteriorated, or already has a second layer, it has to come off. Vantage Roofing checks for trapped moisture first, because wet insulation left under a new roof keeps causing problems.
How fast can someone come out for a leak at my business?
Call (737) 383-1768 and we'll set a time that works around your business hours. If water is coming in right now, say so when you call, so we can talk about a temporary patch or tarp first. For an older leak or a storm check, we'll schedule a regular inspection and photograph the roof before quoting any work.
Does a commercial roof repair have to meet Austin's cool-roof rule?
Usually not. Austin's energy code amendments exempt repairs covering less than half of the roof surface or less than 2,000 square feet, whichever is smaller. A full re-roof over cooled space generally does need a reflective surface that meets the code. Vantage Roofing will tell you during the inspection which rules apply to your building and roof.
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