The ZVSHK commentary, written by a competent team of authors, provides a practical description of the differentiated and simplified calculation methods for determining the pipe diameters of drinking water installations. In contrast to a simplified calculation according to DIN EN 806-3, which can only be applied to residential buildings with a maximum of six units, the differentiated calculation of pipe diameters according to DIN 1988-300 takes all influencing factors into account. Both standards are commented on section by section and are vividly illustrated with numerous tables and diagrams.