Why airtight construction?

Airtightness is essential for an efficient and rational ventilation. Through pressure differences between the inside and outside environment, leaks and chinks lead to air currents, spreading of smells and pollution, excessive energy use and draught.

In winter, cold air can enter the building via the windward  side, causing draught and cold floors, and possibly the introduction of damaging substances (fibres, dust particles). On the leeside of the wind, moist hot air is sucked out, leading to higher heating costs, or worse, condensation problems. In multi-familty dwellings, office buildings, ... the lack of airtightness can have side effects, such as reduced acoustic performance, reduced fire protection, ...

Source: Passiefhuis - Platform