Fiber (composite and combi pipe) pipes are designed for pressurized systems used in indoor hot and cold water supply. The outer and inner material of these triple-layer pipes consists of PPRC (Polypropylene Random Copolymer), while the middle layer consists of glass fiber reinforced PPRC. The middle layer of the pipes is distinguished by high insulation properties, has a lower linear expansion coefficient, and the pipes are less prone to deformation at high temperatures. When used at a temperature of 20°C and PN 25 bar, the service life of glass fiber pipes is 50 years.