This European Standard is applicable to water based surface heating and cooling systems in residential, commercial and industrial buildings. The methods apply to systems integrated into the wall, floor or ceiling construction without any open air gaps. The methods do not apply to heated or chilled ceiling panels or beams. This European Standard provides steady-state calculation methods for determination of the heating and cooling capacity (part 1). This European Standard estimates an equivalent system resistance to be used in dynamic building simulation programs. This European Standard applies also, as appropriate, to the use of other fluids instead of water. A separate standard provides a method for design, dimensioning and installation of the system (part 2). This European Standard is not applicable for testing or certification of systems. A separate standard provides a method and guidance on how to optimise the design for use of renewable energy sources and take system dynamic effects into account (part 3).