airtightness requirements

The requirements concerning airtightness of the building envelope were introduced into the national standard ČSN 73 0540-2 in 2002. Until now the proof of compliance has not been mandatory. The compliance should be checked by means of testing according to the ČSN EN ISO 9972 standard (introduced in 2016 and translated into the Czech language in 2017).

However, the ČSN 73 0540-2 standard only sets the requirements but gives no further information about the time of test and the building preparation or other guidance beyond the ČSN EN ISO 9972 standard.

The current French EP regulation called “RT 2012” imposes a maximum airtightness level2 of residential buildings envelope: 0.6 m³.h^-1.m^-2 for single-family houses and 1 m³.h^-1.m^-2 for multi- family buildings. The respect of these requirements must be justified either with an airtightness test of each building or by the application of a certified quality management approach on the building airtightness. In both cases, airtightness tests must be performed by a third-party tester, qualified by the certification body, Qualibat.

Legislative drivers and new research with demonstrated energy impact on the importance of building and ductwork airtightness are leading to increased activity in this aspect of building energy performance. The paper reviews examples of European countries that account for both building and ductwork airtightness and thus include in their energy performance regulations required or recommended minimum airtightness levels with or without mandatory testing. It addresses incentives through calculation procedures and subsidies that reward a good level of building airtightness.