Roofing is a system, not a commodity
What PVC roofing is and what sits underneath it
PVC stands for polyvinyl chloride. A PVC roof membrane is a flexible, reinforced sheet that is rolled out across a low-slope roof. Where sheets overlap, the seams are heat welded with hot air so the two layers fuse into one continuous piece.
Welded seams are the main reason owners pick PVC. A properly welded seam is not relying on glue or tape. It becomes part of the membrane, and it can be probed and tested during installation.
Like any commercial roof, PVC performs as an assembly. The deck, any vapor control layer, insulation, cover board, membrane, attachment method, flashings and drainage all have to work together. A good proposal spells out each layer, not just the membrane name.
Blue Peaks approach: before recommending PVC, we confirm what the building needs. If grease, chemicals or heavy exhaust are not part of the picture, a different membrane may serve you just as well for less money.
A typical PVC roof assembly
1. Structural roof deck
Steel, concrete or wood depending on the building.
2. Vapor control layer
Used where building use or interior humidity calls for it.
3. Roof insulation
Often polyiso, with tapered insulation where slope is needed.
4. Cover board
A firmer layer that helps with impact and foot traffic.
5. PVC membrane
The reinforced, heat-welded weathering surface.
6. Flashings and drainage
Curbs, walls, pipes, edges, drains, scuppers and exhaust fans.