The airtightness of the building envelope - anning them, executing and measuring them professionally, achieving the target energy standard and the desired level of comfort, as well as guaranteeing functioning ventilation systems remains a discipline comprising a very large extent of knowledge. The Symposium will provide the opportunity to present existing and new knowledge, as well as to promote the exchange among all those involved in the construction industry, consequently making knowledge application in everyday practice easier. The accompanying exhibition will show products and technologies related to the airtightness of buildings.