Buildings with a useful floor area over 1000 m2 which undergo a major renovation have to meet minimum energy performance requirements (in so far as this is technically, functionally and economically feasible). The minimum energy performance requirements may be set in two different ways:
1. for the renovated building as a whole
2. for the renovated systems or components
The objective is the improvement of the overall energy performance of the building.
Note that Germany, for example, also sets minimum requirements for buildings that have a useful floor area less than 1000 mý.
Authors: Hans ERHORN and Heike ERHORN-KLUTTIG (FHG)