TPO, Modified Bitumen, and Foam
Flat & Low-Slope Roofing for Commercial Buildings
We install and repair TPO, modified bitumen, and foam, matched to how your building is used.
Choosing the System Is the Job
No Single Membrane Fits Every Flat Roof
A flat roof is an assembly of membrane, insulation, drainage, and the flashing details that seal every vent and edge. The right membrane is the one that suits the rest of that assembly. How the building is used, how water leaves the roof, what is already installed up there, and how much sun and foot traffic the surface takes all drive the choice.
That is why our recommendation starts with walking your roof and checking how it actually drains. And if your building calls for standing seam or another metal system instead, that work has its own page: see our commercial metal roofing systems.
TPO
TPO Single-Ply Roofing
TPO, short for thermoplastic polyolefin, is a single-ply membrane: one continuous layer of flexible white sheeting rolled out across the roof and joined with hot-air welds. The white surface reflects sunlight, which matters on a roof that bakes from May through September.
It fits wide, simple roofs best. Warehouses and retail strips let the sheets run long with few penetrations (the spots where pipes, vents, and rooftop units come through the roof), and on the right building TPO delivers a clean, reflective roof without the weight of a layered system.
When TPO fails, it fails at the details. Seams welded too fast or too cool, flashing at pipes and curbs, and terminations at walls and edges are where the water gets in; the open field of the membrane is rarely the problem. Patience at the seams decides how long the roof lasts.
Modified Bitumen
Modified Bitumen Roofing
Modified bitumen is asphalt sheet roofing reinforced with polymers, installed in overlapping rolls, and it has been sealing low-slope roofs for decades.
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Step 1: A sound base comes first.
The deck is checked and the base sheet anchored to it. A wet or soft deck gets corrected before any waterproofing goes down, because no layer above can fix what is failing underneath.
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Step 2: Each ply bonds over the one below it.
Rolls go down torch-applied, cold-adhesive, or self-adhered, with the laps offset so water never gets a straight path through the system. That redundancy is why buildings with rooftop equipment and regular maintenance traffic keep choosing it.
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Step 3: Laps and edges take the unhurried work.
This is where a rushed crew shows. A lap that never fully bonded or an edge detail cut short opens up as the roof expands and contracts, and that is where modified bitumen leaks begin.
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Step 4: A granulated cap sheet finishes the surface.
The top ply carries a mineral surface that shields the asphalt from the sun and stands up to foot traffic better than a bare membrane.
Foam
Spray Foam Roofing
Spray polyurethane foam is applied as a liquid that expands into a rigid, continuous layer over the entire roof, then gets sealed under a protective coating.
- One monolithic surface.The foam flows around every pipe and curb, so there are no seams or laps to fail.
- Insulation built into the waterproofing.The same layer that sheds water also insulates the deck beneath it.
- A fit for irregular roofs.Buildings crowded with penetrations and rooftop equipment are where foam makes its case.
- The coating does the protecting.Sunlight degrades bare foam, so the coating over it is the wear surface, not trim.
- Renewal instead of tear-off.A foam roof in sound condition is recoated when the surface wears rather than stripped and replaced.
- Upkeep is part of the deal.Foam holds up for owners who inspect and recoat on schedule. Skip the schedule and the coating wears through before anyone notices.
Repair or Replace on a Flat Roof
Should You Repair or Replace?
Flat roof repair is the right call when the insulation below the membrane is dry and the leak has a findable entry point. We trace the water through the system instead of patching where the stain shows: see how we handle commercial roof repair. When the assembly is saturated or the seams are failing across the field, we say so, and the conversation becomes replacement.
Storm damage on a commercial building gets the same claims advocacy we bring homeowners. When the adjuster schedules the inspection, that appointment includes us, and the estimate we take into negotiation comes from Xactimate, the carrier’s own pricing system. We can’t control what a carrier approves, but you won’t carry the claim alone. Read how our insurance claims process works.