Terminology

• PVC: polyvinyl chloride; made flexible with plasticizers
• KEE: ketone ethylene ester; polymer alloy used in PVC/KEE membranes for plasticizer permanence
• Scrim-reinforced: polyester reinforcement for mechanically attached systems
• Fleece-backed: felt-backed sheet for adhered systems
• Plasticizer migration: loss of plasticizer over time; causes shrinkage and embrittlement in older or poor formulations
• Hot-air welding: fused seams; reweldable in service
• Incompatibility: PVC must be separated from asphalt, coal tar, and polystyrene insulation with slip sheets
• Coated metal: PVC-laminated sheet metal for edges and flashings, welded to the membrane

Standards

Thicknesses

• Sheet thickness set by manufacturer and warranty; specify both overall thickness and thickness over scrim
• ASTM D4434 requires at least 16 mils of material over the scrim, measured per ASTM D7635; thickness tolerance about plus or minus 10 percent

Ratings

• Wind uplift by tested assembly (FM, UL)
• Fire classification as an assembly; PVC is inherently fire-retardant
• Cool roof ratings from CRRC

Test standards

• ASTM D4434: PVC sheet roofing
• ASTM D6754: KEE-based sheet roofing
• ASTM D7635: thickness over scrim
• FM 4474, UL 580, UL 1897: wind uplift
• ANSI/SPRI ES-1 and RP-4
• ASTM E108 / UL 790

Materials

• Membrane: white, tan, gray, and custom colors; reinforced or fleece-backed
• PVC/KEE membranes: restaurants, chemical exposure, and long warranties
• Insulation and cover boards: polyiso with gypsum or high-density cover board; slip sheet over incompatible materials
• Accessories: PVC-coated metal, prefabricated boots, walkway rolls
• Decorative ribs: applied profiles that mimic standing seam on visible roofs

Detailing

• Separate from asphalt-based materials and EPS/XPS with approved slip sheets
• Weld flashings to coated metal edges and counterflashings
• Use walkway pads around rooftop units and grease exhaust
• Slope to drains with tapered insulation and crickets
• Fasten perimeters and corners per the tested assembly

Uses

Specific uses

• Restaurants and food processing (grease exposure)
• Hospitals, labs, and chemical exposure areas
• Vegetated roofs and plaza decks (root-resistant formulations)
• Visible roofs with color or rib profiles
• Reroofing over existing single-ply with slip sheets

Pros and cons

Pros

• Resistant to grease, many chemicals, and fire
• Strong, reweldable seams
• Long track record in Europe and the US
• Reflective and colorable

Cons

• Higher cost than TPO and EPDM
• Incompatible with asphalt and polystyrene without separation
• Plasticizer loss in lower-quality sheets
• Less flexible in cold weather during installation

Manufacturing and cost

Construction

• Calendered or extruded sheets with scrim or fleece; installed like TPO with welded seams

Main manufacturers and suppliers

• Sika Sarnafil
• Carlisle SynTec
• Duro-Last
• Johns Manville
• GAF
• Versico

Trade associations: National Roofing Contractors Association and SPRI.

Typical costs

• PVC roof, installed, with insulation: $6 to $16 per sq ft; higher with KEE membranes and long warranties

Sources

• Carlisle SynTec: understanding ASTM standards for roofing membranes, https://www.carlislesyntec.com/en/Resources/Media/Blog-Landing-Page/SpecTopics/2021/12/16/Understanding-ASTM-Standards-for-Roofing-Membranes
• ICC-ES: ESR-1463 Carlisle EPDM, PVC, and TPO roofing, https://icc-es.org/wp-content/uploads/report-directory/ESR-1463.pdf
• Professional Roofing: TPOs face a changing landscape, https://professionalroofing.net/articles/article/4063
• Roof Observations: single-ply roof cost guide, https://roofobservations.com/single-ply-roof-cost-guide/
• Fixr: flat roof materials and costs, 2026, https://www.fixr.com/articles/best-flat-roof-materials
• Wikimedia Commons: Roofing Membrane Failure 1.jpg, by GRALISTAIR (CC BY-SA 4.0), https://commons.wikimedia.org/wiki/File:Roofing_Membrane_Failure_1.jpg