If you own or manage a commercial building in Jacksonville with a flat or low-slope roof, there’s a good chance it’s covered by some kind of membrane. So, what is membrane roofing? It’s a continuous waterproof layer, either rolled out in sheets or built up on site, that covers a roof too flat for shingles or tiles to shed water. Membranes are used on many types of commercial roofing systems on warehouses, retail centers, offices, and industrial buildings.
Why Flat Roofs Need a Membrane
Shingles and tiles work on steep roofs because each piece overlaps the one below it, and gravity pulls water down and off before it can work its way under the laps. On a low-slope roof, water moves slowly and can sit for hours after a storm. Overlapping pieces would leak. A membrane solves that by forming one sealed surface with welded, taped, or bonded seams, so standing water has no path into the building.
In Jacksonville, summer afternoon thunderstorms and tropical systems during hurricane season, which runs from June 1 through November 30, can put a lot of water on a roof in a short time, and the membrane has to keep all of it out.
What Is Membrane Roofing Made Of?
Membrane roofs fall into two broad groups. Single-ply membranes are factory-made sheets installed in one layer. Asphalt-based membranes, including modified bitumen and built-up roofing, use multiple layers bonded together.
Single-ply membranes
TPO and PVC are thermoplastic sheets, usually white, with seams joined by hot-air welding. The welded seam becomes part of the membrane itself. Their white surface reflects sunlight, which helps keep rooftop temperatures down under Florida sun. TPO roofing is a common choice on new commercial roofs and replacements.
EPDM is a synthetic rubber membrane, most often black. Because it’s a thermoset, its seams are joined with tape and adhesive instead of heat. EPDM stays flexible through temperature swings and has been used on low-slope roofs for decades.
Modified bitumen
Modified bitumen starts with asphalt blended with polymers, then formed into reinforced sheets at the factory. According to the Florida Roofing and Sheet Metal Contractors Association, the two main types are SBS, which is highly flexible, and APP, which is known for aging well. Sheets go down with heat, hot asphalt, or cold adhesive, usually in two or more layers with a granule-surfaced cap sheet on top. The layered build makes modified bitumen roofing a common pick for roofs that see regular foot traffic.
Built-up roofing
Built-up roofing, often called BUR or tar and gravel, alternates layers of bitumen with reinforcing felts or fabric. The top is finished with gravel, granules, or a coating.
Spray Foam and Coatings
Spray polyurethane foam isn’t a sheet membrane, but it serves a similar purpose. The foam goes on as a liquid, expands, and cures into a seamless layer that also insulates. It needs a protective coating on top to shield it from UV exposure. Our spray foam roofing work in Jacksonville includes both the foam and the coating.
Roof coatings in acrylic, silicone, polyurethane, or urethane can also be applied over many existing membranes to extend their life. On an aging TPO roof that’s still sound, TPO roof restoration with a coating can be an alternative to a tear-off.
Choosing a Membrane for a Jacksonville Building
The right membrane depends on how the building is used, how much traffic the roof gets, the condition of the deck, and the budget. A restaurant with grease exhaust on the roof has different needs than a warehouse with a few HVAC units. A roof with heavy foot traffic may do better with a multi-ply modified bitumen system, while a large, simple roof may be a good fit for a single-ply membrane.
Florida also has a product approval step. Jacksonville Beach’s permit paperwork, for example, asks for the manufacturer, product description, limits of use, and Florida product approval number for each roofing product on the job, with product types ranging from underlayment to spray-applied polyurethane. Statewide approvals can be looked up through the Florida Building Commission, and any membrane system you consider should have that approval in place.
Signs Your Membrane Roof Needs Attention
Membrane problems usually show up first at seams and edges. Watch for seams that have opened or wrinkled, flashing pulling away from walls and curbs, blisters or bubbles, cracked or bare spots on a granule-surfaced cap sheet, and water that sits in the same low spot days after a storm. Inside the building, ceiling stains and musty smells near the top floor are worth tracing back to the roof.
A commercial roof inspection after a major storm can catch a lifted edge or an open seam before water reaches the insulation. Wet insulation is often what turns a small repair into a much larger one.
How WaterTite Works With Membrane Roofs
WaterTite Commercial Roofing installs, repairs, and replaces TPO, PVC, EPDM, modified bitumen, and spray foam roofs on commercial, agricultural, and industrial buildings around Jacksonville. We have six years on the commercial side and more than 20 years of roofing industry experience. All of our contractors are Conklin certified, we’re licensed and insured, and we use the highest quality materials on every system.
Every project starts with a drone inspection, and you’ll have a free estimate within 24 hours. Our pricing is upfront and transparent. Roofs we install carry a standard 5-year workmanship warranty, which we extend to match the material warranty when you schedule an annual inspection with us. Every commercial roof replacement includes free gutter cleaning, and if a storm damaged your roof, our crews are storm damage restoration experts who will walk you through the insurance process.
Knowing the answer to “what is membrane roofing” helps you follow the options, but picking the right system still depends on a close look at your roof. If you’re deciding which membrane fits your building, talk with a commercial roofing company in Jacksonville that installs and repairs these systems. Contact us to schedule your free drone inspection.
