How much insulation?
The dimensioning of the thermal insulation of a building is normally based on the requirements stipulated by the relevant national building regulations.
Requirements are traditionally given as maximum allowed thermal conductance, so called U values expressed in W/m2 K, watts per square meter and degree Kelvin temperature difference, and given for each specific structure in the building.
The required U values vary from country to country and even within a country based on the climatic zones. Based on the U values, the required insulation thickness of each structure e.g. wall, roof, floor, etc. can be determined.
Adoption of the Energy Performance Directive
Recently the European Parliament passed the Energy Performance Directive which will have profound implications on the insulation of buildings. This directive compels the Member States to develop the thermal insulation regulations into energy-use-regulations setting the requirements on the amount of energy used in the heating and air conditioning of buildings.
The rationale is primarily the environmental concerns linked to the emissions and the commitments made by signing the Kyoto pact. The directive also compels the Member States to establish a certification scheme for the monitoring of the energy use in the buildings. These certificates have to be presented every time a building or a part of it, say an apartment in it is being sold or rented to a new tenant. The directive is applied both to the new and old buildings with certain restrictions.
Sustainability – challenge of tomorrow
|
