Airtightness

… and still fresh air to breathe!

Why do buildings have to be airtight?

The highest possible airtightness of external components reduces energy losses due to uncontrolled airstreams and prevents the formation of harmful condensation water inside components due to ingress of moist air.

A complete airtight level on the inside of the building envelope requires both the legally prescribed Energy Saving Ordinance (EnEV) and the legally binding DIN 4108-2. The Passive House Institute currently places the highest demands on buildings that are to be certified as passive houses.

In general it can be said that the planning and execution of the airtightness of an object have to be given the same importance as the thermal protection, the ventilation as well as the summer heat protection. It is clear that a holistic view is more than just the sum of all the individual points.

Airtightness measurement (BlowerDoor® measurement)

If the planning of a building is targeted on an air-tightness test from the very beginning, a reduced ventilation heat loss can be taken into account when calculating the energy demand. This has an effect on the overall efficiency of the building and leads to a significantly better result, which is also reflected in reality.

If a BlowerDoor® measurement is carried out during the shell construction phase for quality assurance, unwanted leaks can be located and repaired. This prevents subsequent structural damage, ensures a high-quality building envelope and provides an excellent value for airtightness during acceptance measurements.

An acceptance measurement is always necessary if this has been agreed from the beginning or if it has been included in the energy demand calculation according to EnEV or if a ventilation system with heat recovery is installed. However, it may also be required for certifications (e.g. Passive House, KfW Efficiency House, DGNB, LEAD, etc.).