Setting of minimum energy performance requirements
Article 5
1. Member States shall take the necessary measures to ensure that minimum energy performance requirements for buildings or building units are set with a view to at least achieving cost-optimal levels and, where relevant, more stringent reference values such as nearly zero-energy building requirements and zero-emission buildings requirements. The energy performance shall be calculated in accordance with the methodology referred to in Article 4. Cost-optimal levels shall be calculated in accordance with the comparative methodology framework referred to in Article 6. Member States shall take the necessary measures to ensure that minimum energy performance requirements are set for building elements that form part of the building envelope and that have a significant impact on the energy performance of the building envelope when they are replaced or retrofitted, with a view to achieving at least cost-optimal levels. Member States may set the requirements for building elements at a level that would facilitate the effective installation of low temperature heating systems in renovated buildings. When setting requirements, Member States may differentiate between new and existing buildings and between different categories of building. Those requirements shall take account of optimal indoor environmental quality, in order to avoid possible negative effects such as inadequate ventilation, as well as local conditions and the designated function and the age of the building. Member States shall review their minimum energy performance requirements at regular intervals which shall not be longer than five years and shall, if necessary, update them in order to reflect technical progress in the building sector, the results of the cost-optimal calculation set out in Article 6, and updated national energy and climate targets and policies. 2. Member States may adapt the requirements referred to in paragraph 1 to buildings officially protected at national, regional or local level, as part of a designated environment or because of their special architectural or historical merit, in so far as compliance with certain requirements would unacceptably alter their character or appearance. 3. Member States may decide not to set or apply the requirements referred to in paragraph 1 to the following categories of building: (a) buildings owned by the armed forces or central government and serving national defence purposes, apart from single living quarters or office buildings for the armed forces and other staff employed by national defence authorities; (b) buildings used as places of worship and for religious activities; (c) temporary buildings with a time of use of two years or less, industrial sites, workshops and non-residential agricultural buildings with low energy demand and non-residential agricultural buildings which are used by a sector covered by a national sectoral agreement on energy performance; (d) residential buildings which are used or intended to be used for either less than four months of the year or, alternatively, for a limited annual time of use and with an expected energy consumption of less than 25 % of what would be the result of all-year use; (e) stand-alone buildings with a total useful floor area of less than 50 m 2 .