airtightness

Post date: 21 Aug 2009
Type: Publication

This is defined in EN 13829, § 6.1.2. All exterior surfaces, plus floors, ceiling and walls to neighbouring apartments are taken into account. However, other assumptions are used in some countries to extract indicators that better fit the national requirements of the EP-regulations (see question regarding the measurement of multi-family buildings). Anwered by: Rémi Carrié and Gaëlle Guyot (CETE de Lyon) Date: 2008/12/12
Post date: 10 Jun 2009
Type: Ask the Experts

ASHRAE Journal - Vol. 15, No 4 - April 2009 - pages 50-52, 54-56, 58, 60
Post date: 8 May 2009
Type: Publication

Measurements usually show that light (e.g., timber-frame or steel) constructions are leakier than massive construction, but this is not bound to be. In fact, PassivHaus houses are often light constructions and are very airtight. The general statement that can be drawn is that light constructions are more sensitive as the airtight layer can be more affected by poor design and workmanship than in massive constructions. Anwered by: Rémi Carrié and Gaëlle Guyot (CETE de Lyon) Date: 2008/12/12
Post date: 12 Dec 2008
Type: Ask the Experts

To our knowledge, the UK is the only country that has made testing mandatory. This has been in force since 2002 for large buildings and extended to most buildings in 2006. Anwered by: Rémi Carrié and Gaëlle Guyot (CETE de Lyon) Date: 2008/12/12
Post date: 12 Dec 2008
Type: Ask the Experts

There are three major ways to estimate this impact: - the simplest is to evaluate the infiltration losses based on a rule of thumb established by Drubul in 1988 (*) and suggested by Kronvall (**) in 1978. The rule says that the infiltration airflow rate in air changes per hour may be determined by dividing the n50 value by an empirical coefficient that lies between 10 and 30. In practice, the empirical coefficient is often set to 20 (i.e., the infiltration airflow rate is equal to the airtightness at 50 Pa divided by 20);
Post date: 12 Dec 2008
Type: Ask the Experts

Now in Europe, many countries have adopted the n50 value (i.e., the leakage flow divided by the volume) for their EP regulation while others (e.g., Belgium, France, UK) use the envelope area normalisation. The rationale behind this latter choice lies in the fact that the volume is not needed for an energy performance calculation. Using the n50-value should require a precise definition of the way the volume is calculated, which to our knowledge, is not the case in any European country. On the other hand, the envelope area is usually well-defined in regulations.
Post date: 12 Dec 2008
Type: Ask the Experts

There is no up-to-date document at this time. Anwered by: Rémi Carrié and Gaëlle Guyot (CETE de Lyon) Date: 2008/12/12
Post date: 12 Dec 2008
Type: Ask the Experts

The airtightness measurement of single apartments is usually performed the same way as in individual houses. Therefore, there is no specific protocol to balance the pressure between the apartment under test and other apartments. Different protocols may lead to very different results. Anwered by: Rémi Carrié and Gaëlle Guyot (CETE de Lyon) Date: 2008/12/12
Post date: 12 Dec 2008
Type: Ask the Experts