The pipe network forms the distribution system for liquid or gaseous media in building services engineering. It comprises flow and return pipes, risers, and distribution lines. Dimensioning is based on hydraulic calculations considering pressure losses, flow velocities, and volume flows. Hydraulic balancing is essential to ensure all consumers receive an equal supply of heating or cooling medium. Pipe materials vary by application: copper, steel, galvanized steel, or plastics such as PE-X or PP-R. Corrosion protection, insulation against heat loss, and proper fixing and expansion compensation are key planning aspects for a permanently functioning pipe network.