market

The Energy Performance of Buildings Directivementions that each member states' energyperformance (EP) calculation methodology mayinclude envelope airtightness. In fact, manymember states have included envelopeairtightness in their EP calculation method.Many countries have also specific requirementsfor ductwork airtightness. However, they seemto be unequally successful in achieving a markettransformation. This paper describes themechanisms that have been used in somecountries, with a special focus on success storieswhich could inspire other member states.