A monthly method for calculating energy performance in the context of european building regulations

The European Energy Performance in Building Directive (EPBD) requires methods for the calculation of the energy performance for use in the context of building regulations. 
The paper describes the rationale behind the development of a simple monthly method for the calculation of the energy needs for heating and cooling of buildings, and positions this method in the field of different possible calculation approaches. 
In the light of special requirements in the fields of transparency, robustness and reproducability that are imperative when calculating the energy performance in the context of building regulations (in particular when checking compliance with a legal upper limit to an energy performance level) and in the light of the target audience for this kind of calculations the simple monthly calculation method seems a suitable contender for an EPBD calculation method. First series of validation tests show that the simplified method is well suited to be used in both warm, moderate and cold European climates.