DIN V 18599-2:2016-10

DIN V 18599-2 specifies methods of calculating the energy needs for heating and cooling of the section of the building being assessed. The calculations are based on a specific zone of the building defined according to its intended use. The method of defining building zones is described in DIN V 18599-1. DIN V 18599-10 specifies boundary conditions with respect to room temperature, internal loads, lighting and air change requirements relating to usage.
The procedures compiled in DIN V 18599-2 are suitable for calculating the energy need for heating of building zones which have only heating, as well as the energy needs for heating and cooling of building zones which are served by both heating and cooling systems. Particular attention is paid to determining the energy needs for heating and cooling of building zones equipped with ventilation and air conditioning systems. Methods to determine the total energy needs for heating and cooling of buildings with ventilation and air conditioning systems are described in DIN V 18599-3, which specifies the heat, cooling energy, steam and electrical energy required for operating fans for air handling and transport.
To calculate the energy needs for heating and cooling, all heat sources and sinks within the building zone shall be determined and included in the balance calculations. These calculations shall also include the results of other calculations described in other parts of the DIN V 18599 series of prestandards (for example, energy gains due to artificial lighting as described in DIN V 18599-4, uncontrolled heat gains due to the heating system as described in DIN V 18599-5, etcetera).
Energy needs for heating and cooling are the result of interaction between the technical characteristics of the building and the building's technical installations and equipment and of the requirements arising from the type of usage. Potential energy savings which may be achieved by modifications to the building can be estimated by determining the energy needs for heating and cooling.
The energy needed for heating and, where applicable, for cooling the building zone shall be provided by heating and cooling systems. The energy used by the heating and cooling systems for supplying energy to the zone being evaluated is determined in DIN V 18599-5 to DIN V 18599-9. The values of energy need calculated according to this document are the basis for calculating the energy use of the heating and cooling systems.
The method is not suitable for calculating the energy needs for heating or cooling of building zones with double glass façades. As long as no generally approved method of calculating energy characteristics of double glass façades is known, all façades of this type which are subdivided into individual storeys can be included in the calculations by being treated as sunspaces (unheated glazed annexes).
DIN V 18599-2 has been approved by NA 005-12-01 GA "Gemeinschaftsarbeitsausschuss NABau/FNL/NHRS: Energetische Bewertung von Gebäuden" ("Joint Working Committee NABau/FNL/NHRS: Energy performance of buildings") and published as a prestandard.