J. Langmans, R.Klein, P. Eykens, M. De Paepe, S.Roels
Bibliographic info:
4th International Symposium on Building and Ductwork Air Tightness - BUILDAIR (former European Blower Door Symposium), 1-2 October 2009, Berlin, Germany

This paper investigates the practical feasibility of an exterior air barrier for the construction of a recently constructed light weight passive house in Ghent, Belgium. The paper discusses the results of pressurisation tests, conducted in the different construction stages of the building envelope. The windbreaker, which will also act as an air barrier, consists of bituminous mixed wood fibres plates with a watertight bitumen impregnated layer on the top face. Measurements have been performed with and without sealing the joints. In addition to in situ pressurisation tests of the entire building, laboratory measurements on specimens of the windbreaker including typical joints were carried out in order to quantify the influence of possible local air leakages. The measurements indicate that the external wind barrier contributes significantly to the final airtightness of the tested building. In this case study, sealing only the most critical joints of the outer shell already leads to a level of airtightness of the whole building envelope which fulfils the requirements of the passive house standard (less than 0,6 air changes per hour (ACH) at 50 Pa). The results presented in this paper indicate that the proposed solution has a potential to reduce labour costs required to reach a sufficient level of airtightness.