TPO (Thermoplastic Polyolefin) combines the best of two worlds: the long-term flexibility of rubber and the extreme reliability of hot-air welded thermoplastic polymers. Produced in white reflective sheets, it is the heart of high energy-efficiency roofing systems.
TPO is a thermoplastic material. Under a jet of hot air (about 500-600°C) from Leister machines, overlapping edges melt for a fraction of a second. Pressed by a silicone roller, they fuse at the molecular level, creating an indestructible monolithic joint. Unlike PVC, TPO contains no chemical plasticisers: it does not harden or shrink over the years.
The white colour of TPO provides a high Solar Reflectance Index (SRI > 100). While a black bituminous roof can reach 80°C in summer, a white TPO membrane rarely exceeds 35°C. This dramatically reduces cooling costs and increases the yield of bifacial photovoltaic panels installed on the roof.
Standards
European and international references applicable.
Physical properties
Usage environment
Being white, the roof tends to show dirt and water staining faster than black membranes. This does not affect waterproofing performance but to maintain maximum Cool Roof efficiency, periodic washing (every 2-3 years) is recommended.