The Building Regulations with regard to the energy performance of buildings in the Netherlands is an attempt to a performance oriented requirement in conjunction with a test standard. The test standard in fact means a calculation procedure. The requirements are given in the Dutch Building Decree. This Decree is coupled to the building act. Within the scope of an application for a building permit is has to be proven that the energy use of the building does not reach the maximum allowed energy amount set for that building. The check on the energy performance of a building is thus a so called pre check before the building is being built. The energy use in reality depends on a number of parameters of which the use of the building is a very important one. In the test these parameters have normalised values derived from actual values in practice. This means that the calculated energy use of a single building will not be in accordance with the actual energy use of that building. But, for the whole building stock we assume that it will be in accordance with the real energy use of the building stock. The energy saving calculated on country level may be expected to be reasonably reliable. The energy performance is expressed as an Energy Performance Characteristic (EPC).