BlowerDoor test mandatory for ventilation system and KfW70

We had not given it any thought until now. At the beginning, it was not yet decided for us whether we would even install a ventilation system. Since we are contracting everything ourselves, the test is also not included for us, but we have to commission and pay for it separately.

By the way, the ventilation setting has nothing to do with the test... only different parameters apply during the test because of the ventilation...

Good day,

We are building a KfW70 house and have decided on a ventilation system with heat recovery for comfort reasons. Are we required to do a BlowerDoor test?

If a ventilation system is planned and funding is to be applied for, a BlowerDoor test as proof of airtightness is mandatory.

Best regards from the Rhineland

The ventilation setting has nothing to do with the test by the way... only different parameters apply during the test because of the ventilation...

In my opinion, more clearly put: for a ventilation system to work flawlessly and efficiently, increased requirements regarding the airtightness of the building apply. Rhineland regards

In my opinion, formulated more clearly: in order for a ventilation system to work flawlessly and efficiently, there are increased requirements for the airtightness of the building.

Rhenish regards

That sounds better

Isn't the BDT mandatory for KFW houses anyway?