PVC: the specialist for demanding roofs

Every restaurant exhaust fan rains a fine mist of grease onto the roof around it, and grease degrades most membranes years ahead of schedule. PVC's chemistry resists that exposure far better than standard single-plies, which is why food service, kitchens, and processing facilities commonly spec PVC. Add hot-welded seams and strong reflectivity, and it's a premium membrane that earns its price on the right building.

PVC also carries one of the longest performance histories among weldable membranes. For buildings without chemical exposure, TPO usually pencils out better, and we'll tell you so. This is about matching chemistry to what your roof actually endures.

PVC is commonly offered in nominal thicknesses around 50, 60, and 80 mil (a mil is a thousandth of an inch), with exact figures varying by manufacturer and product line. As with any single-ply, the thickness above the reinforcing scrim is the membrane's weathering allowance, thicker sheets weather longer and typically qualify for longer warranty terms.

On high-exposure roofs, the very buildings that choose PVC, we lean toward the heavier end. A kitchen roof works harder than an office roof, and the increment for thicker membrane is small against the cost of replacing a degraded one early.

Rooftop grease doesn't stay near the fan. It spreads with wind and rain across a wide zone, and on most membranes it slowly softens the surface until seams and details fail. PVC's resistance buys time, but membrane chemistry should be the second line of defense, not the first: exhaust-fan discharge should be managed with containment systems and regular service so the roof isn't the grease trap.

For restaurants, groceries, and food processing across South Mississippi, our usual pattern is PVC where exposure is real, honest containment detailing at the fans, and a maintenance cadence that keeps the exposure zones inspected. That combination is what actually gets these roofs to a full service life.

PVC installs mechanically attached or fully adhered over a continuous substrate, like every membrane, it never spans open framing, and the insulation and cover board below it are specified as their own components. Over certain existing materials, PVC needs a separation layer: some substrates (including asphalt products and polystyrene insulations) can interact badly with the membrane, so compatibility drives the assembly design.

Drainage rules don't bend for premium membranes either. Ponding water is never harmless, and the design targets positive drainage, commonly around a quarter inch per foot where practical, with walk pads at serviced equipment so kitchen and HVAC techs aren't grinding grit into the sheet.