PVC Roof Membrane
Unlike TPO, which is relatively new to the single-ply roofing market, PVC is a thermoplastic membrane that has been being used for commercial roofing since the 1960s. The physical properties of PVC are enhanced by a highly durable, weft-inserted polyester fabric that is encapsulated by thick PVC-based top and bottom plies making it resistant to chemicals, grease, fire and punctures. PVC membranes come in 50, 60 and 80 mil and the smooth surface of the PVC membrane allows for a total-surface fusion and permanent weld, creating a consistent watertight monolithic roof assembly.
Because of its thermoplastic makeup, minimal components are required to install a PVC roofing system using an automatic heat welder, making the welding fast, clean and consistent. Prior to installation a coverboard and layer of insulation are installed and then the PVC can be attached fully adhered or mechanically fastened.
Fully Adhered PVC System -
As with a TPO or EPDM membrane, the fully adhered option is where the membrane is bonded to the deck’s substrate utilizing PVC bonding adhesive. An adhered system provides the highest level of stability and uplift protection and generally would be a higher cost than a mechanically attached PVC roof. Fully adhered systems are preferred in locations with higher winds.
Mechanically Attached PVC System -
A mechanically attached PVC membrane is the most widely used type of installation utilizing fasteners to attach the membrane through the insulation and into the structures deck 12” on center along every seam of the membrane. All seams are hot welded to provide a watertight seal.
Pros of Mechanically Attached PVC: Can be installed in any temperatures. Lower costs of this system is often a mechanically attached system is chosen.
Best Use for PVC Membrane:
PVC has a proven record of durability over the less time tested TPO. Because of it’s resistance to grease, fire and heat, we would recommend a PVC on roofs that have exhaust vents and those roofs where ponding may be an issue but are also located in the energy efficient regions of 1- 3.
The following characteristics of an PVC membrane include:
- Superior Resistance to chemicals, grease, fire and animal fat
- Provide a cooling factor to buildings located in warmer regions
- Durable protection proven since the 1960s
- Low thermal conductivity for heat and UV resistance
- Ease of repair
All WNC Roofing’s PVC roof installations come with a 20-year manufacturer’s warranty that stands behind the integrity of the product. WNC Roofing adheres to the manufacturer’s installation requirements to maintain the 20-year warranty for all roofs we install.
A post installation inspection is conducted by the manufacturer following each of WNC Roofing’s projects before a final sign-off for the 20-year warranty is approved. Additionally, WNC Roofing provides a two-year workmanship warranty to cover all installation aspects.