DIN EN ISO 13789:2008-04

The document specifies a method and provides conventions for the calculation of the steady-state transmission and ventilation heat transfer coefficients of whole buildings and parts of buildings. It is applicable both to heat loss (internal temperature higher than external temperature) and to heat gain (internal temperature lower than external temperature). For the purpose of this standard, the heated or cooled space is assumed to be at uniform temperature. Annex A provides a steady state method to calculate the temperature in unheated spaces adjacent to heated buildings.