ᐅ Blower door test result for KfW 55 standard

Hello everyone,

I’m a bit “surprised” by the result of our blower door test:

We achieved a value of 1.5 1/h (n50) (the maximum allowed is exactly 1.5 1/h).

Yes, the requirements for a KfW55 house are met, but it still makes me somewhat uneasy.

What values have you achieved, and can anyone guess what might be causing this?

Our detached house:

- with a usable basement
- with an air-to-water heat pump + central controlled residential ventilation
- solid construction with filled 36.5 cm (14.4 inches) bricks

You will still receive a report.
It will specify what is leaking.
Was the construction already fully completed?

I believe we had 1.3, but our window sills were not installed yet. You could really feel the drafts because of that. Also, our attic was not fully finished at that time. So if your construction is not completely finished yet, I wouldn’t worry at all, and otherwise, you can check the final report.

RotorMotor schrieb:

You will still receive a report.
It states what is leaking.
Was the construction already completely finished?

Here are the comments, which I have just received by email:

The general contractor only had our airtightness test carried out once everything was completely finished. I thought to myself, "That’s bold." At the same time, we were concerned about what might need to be reworked, as we wanted to move in shortly afterward. The result of 0.57 made us breathe a sigh of relief. Obviously, the general contractor was very confident that the test would be passed without any issues. For our project as an Efficiency House 55 EE without mechanical ventilation with heat recovery, the limit value would have been 3.0.

You shouldn’t worry too much. The value is usually much better in a final test. Is the company planning a further test? Otherwise, you might consider paying for one yourself to get a good result.

Why would you need this if it has already been approved?
Perhaps only when selling. In that case, it can be done then, or is it expected that more discrepancies will develop in the meantime?