ᐅ Installing a ventilation system outside?

Hello,

Ram_master_g schrieb:

Sure, when I open the window, air at 0 degrees comes in, but I only ventilate once a day?

I definitely wouldn’t recommend that—especially if you’re building with ETICS (External Thermal Insulation Composite System)! During the first 2 years, you need to ventilate by fully opening windows at least 3 times a day, preferably more often.

Regards, Bauexperte

Hello,

DerBjoern schrieb:
Regardless of the fact that once a day is not enough for modern houses, what does an ETICS have to do with ventilation?

Sometimes I really wonder….

Today’s houses are extremely airtight; even with purely monolithic construction. When a traditional ETICS (External Thermal Insulation Composite System) is applied over the masonry, it becomes even more airtight because the exterior render must be sealed with a synthetic resin-based coating for durability. If ventilation— even decentralized ventilation—is omitted, airing out the house three times a day is generally insufficient during the first years after moving in. Even if the bricks are bonded together, moisture can enter the house through the screed. Each occupant exhales about 1 liter of water vapor per day; showering or bathing adds more moisture; cooking also generates humidity. This moisture must be effectively removed from the house.

In monolithic construction, at least some of the existing moisture can migrate through the masonry to the outside— but only if the walls are not painted with impermeable paint.

With conventional prefabricated houses, however, the moisture is completely trapped inside the building.

Regards, Bauexperte

Sorry, but monolithic and also cavity wall constructions are equally airtight. The small amount of moisture that can be transported through the walls is in the per mille range of what is produced throughout the day. Therefore, ventilation should be considered regardless of the type of insulation.