Why is airtightness so important?
The passage of air through joints and cracks in the building envelope has many disadvantages. For example, a high percentage of all structural damage is caused by leaking building envelopes. The sound insulation is reduced, draughts cause discomfort for the residents and unnecessarily high heat losses are incurred. For this reason, the applicable standards have for many years required that the outer shells of buildings must be airtight.