In December 2002 the European Parliament and the Council adopted a directive on the energy performance of buildings (2002/91/EC).
With the object to improve energy efficiency in buildings across the European Community, the Directive involves:
- the general framework for a methodology of calculation of the integrated energy performance of buildings;
- the application of minimum requirements on the energy performance of new buildings;
- the application of minimum requirements on the energy performance of large existing buildings that are subject to major renovation;
- energy certification of buildings; and
- regular inspection of boilers and of air-conditioning systems in buildings and in addition an assessment of the heating installation in which the boilers are more than 15 years old.
Member States of the European Union were mandated to transpose the first three provisions of the Directive on the Energy Performance of Buildings before 4 January 2006.
For the last two provisions, due to the challenges facing Member States as regards training and accreditation of experts to carry out the certifications and inspections - a further grace period of up to three years (i.e. until January 4, 2009) was allowed.
The methodology of calculation of energy performances of buildings shall include at least the following aspects:
(a) thermal characteristics of the building (shell and internal partitions, etc.). These characteristics may also include air-tightness;
(b) heating installation and hot water supply, including their insulation characteristics;
(c) air-conditioning installation;
(e) built-in lighting installation (mainly the non-residential sector);
(f) position and orientation of buildings, including outdoor climate;
(g) passive solar systems and solar protection;
(h) natural ventilation;
(i) indoor climatic conditions, including the designed indoor climate.
The positive influence of the following aspects shall, where relevant in this calculation, be taken into account:
(a) active solar systems and other heating and electricity systems based on renewable energy sources;
(b) electricity produced by CHP;
(c) district or block heating and cooling systems;
(d) natural lighting.
For the purpose of this calculation buildings should be adequately classified into categories such as:
(a) single-family houses of different types;
(b) apartment blocks;
(d) education buildings;
(f) hotels and restaurants;
(g) sports facilities;
(h) wholesale and retail trade services buildings;
(i) other types of energy-consuming buildings.