PVC
PVC is what you use when the roof has to survive what the building exhausts
PVC and TPO look similar on a roof and install similarly. The difference that matters is chemical: PVC tolerates grease and a range of chemical exposures that will visibly degrade other single-ply membranes, which is why it is the standard specification over a commercial kitchen.
When PVC is the specification, not a preference
- Restaurant and commercial kitchen roofs. Grease-laden vapor settles on the roof surface around the exhaust fan and spreads with rain. This is the classic case.
- Food processing and any facility with animal fat in the exhaust stream.
- Buildings with chemical or solvent exhaust, where the specific chemistry needs checking against the membrane rather than assumed.
- Roofs where grease containment is already installed, which tells you the problem has been recognized and the membrane should match it.
PVC compared with TPO, honestly
| Consideration | PVC | TPO |
|---|---|---|
| Grease and many chemicals | Formulated to resist it | Degrades under grease exposure |
| Seams | Hot-air welded, and welds well across a wide temperature range | Hot-air welded |
| Flexibility over time | Contains plasticizers that migrate slowly over many years, which is the long-term aging mechanism | Ages differently; weathering and surface degradation rather than plasticizer loss |
| Detail work | Welds readily, takes fabricated corners and flashings well | Similar, and both are far better for detailing than adhered systems |
| Where each is usually specified | Kitchens, food, chemical exhaust, smaller complex roofs | Large simple roofs where exhaust is not an issue |
What still has to be right
A grease-resistant membrane does not make grease a non-issue. Grease still collects, still makes a roof slippery and hazardous to walk, and still finds its way into drains. A proper installation pairs the membrane with containment at the fan, a plan for cleaning, and walkway protection on the routes people actually use.
- Grease containment at the exhaust fan, maintained rather than installed and forgotten.
- Walkway pads from the access point to every unit. Roof traffic causes more membrane damage than weather does.
- Drains kept clear. Grease and debris together block a drain faster than either alone.
- Compatibility checked at every contact point. Some materials in contact with PVC — certain asphalt products and some insulations — need a separator, and getting that wrong shows up as degradation along a line rather than at random.
A restaurant roof that has had TPO or EPDM installed under its kitchen exhaust is not an unusual finding. If the membrane around the fan is discolored, softened or cracking while the rest of the roof looks fine, that is what happened.
Roof under a commercial kitchen exhaust?
Talk to us about the buildingIs PVC more expensive than TPO?
The materials differ, and so do the installed scopes, but the more useful framing is that a membrane that degrades under your exhaust is the expensive option regardless of what it cost to install. We do not publish prices on this site; the specification question is answered before the commercial one.
Can we just replace the area around the fan?
Where the membrane is otherwise sound and the degradation is local, a compatible repair with proper containment can buy real time. It is worth being clear that the rest of the roof is now older than the patch, and planning accordingly.
Does PVC work in cold weather?
It welds and performs well across the temperature range this climate produces. Winter installation has its own requirements for adhesives and substrate conditions, which belong in the scope.
What about solar reflectivity?
PVC is commonly white and reflective, in the same way TPO is. Where cooling load is a priority, that is a point in favor of both over a dark membrane.
All work is performed by licensed and insured local roofing professionals.