Reinforced Thermoplastic Polyolefin (TPO) Roofing Membrane
This information reflects our best understanding of product composition in 2021.
Thermoplastic polyolefin (TPO) membranes are a type of single-ply roofing membrane that are commonly made up of two layers of TPO surrounding a woven polyester reinforcing layer, or scrim. While specific chemistry of the TPO polymer may vary...
More about Reinforced Thermoplastic Polyolefin (TPO) Roofing Membrane
Thermoplastic polyolefin (TPO) membranes are a type of single-ply roofing membrane that are commonly made up of two layers of TPO surrounding a woven polyester reinforcing layer, or scrim. While specific chemistry of the TPO polymer may vary between products, they are block copolymers that have a combination of rigid and elastic blocks to provide both thermoplastic and elastomeric properties. The polymers are composed of segments of polypropylene and one or more additional polymers such as ethylene propylene, linear low density polyethylene (LLDPE), or EPDM rubber. Typical additives include UV stabilizers, antioxidants, and pigments. TPO roofing membranes also require flame retardants. While halogenated flame retardants are not common, they could be used in some products. TPO membranes typically do not contain any plasticizers. TPO membranes are usually sold in thickness of 45, 60, and 80 mil sheets and may include up to 15% post-industrial scrap recycled back into the membrane. Similar to other types of single-ply roofing membranes, they are sold in rolls which are applied via mechanical fasteners, site- or factory-applied adhesives, or loose laid with gravel. Membrane seams are heat welded and edges are sealed using tapes or sealants.
A historical version of this Common Product is available here: https://pharos.habitablefuture.org/common-products/2214443