In order to limit the thermal expansion of plastic materials at elevated temperatures, a glass fibre reinforced pipe must be used for surface-mounted hot water applications. The structure of the PP-R pipe consists of 33% PP-R – 33% glass fibre layer – 33% PP-R. In this way, the thermal expansion coefficient α of the plastic pipe is reduced to 0.035 mm/mK. Compliant with: UNI EN ISO 15874 – DIN 8077 – DIN 8078 – CSA B 137.11 – ASTM F 2389 – UNI EN ISO 15494 – ISO 4065