ᐅ Blower Door Test – Meaning of the Result

Created on: 5 Jan 2018 23:51
A
AndreasPlü
Hello,

Today, as the final trade in our already occupied house, we had the airtightness test.

The result: N 50 = 0.68

We built a solid KfW 70 (2017) standard house. What does this mean? Is this good, acceptable, or rather mediocre?

Should we expect particularly harmful leaks? The tester detected a slight leakage at a sliding door but considered it within acceptable limits, which brings us back to the original question.
B
Bieber0815
6 Jan 2018 13:15
AndreasPlü schrieb:
We built a solid KfW 70 (2017) house. What does that mean? Is that good, okay, or rather mediocre?

For comparison, our house, made of calcium silicate bricks plus ETICS, KfW 70, completed in June 2016: n50 = 0.70 h⁻¹.
D
does02
6 Jan 2018 19:22
For us: 0.47
Leaks that still need to be fixed: At the front door seal, there is a draft → will still be adjusted.
And below the kitchen window, there is air leakage → will be sealed again with SIGA tape before the kitchen countertop is installed.

Values below 0.50 are achieved by our inspector only about 10 times per year, while he performs approximately 150 blower door tests per year.
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Bieber0815
6 Jan 2018 22:44
does02 schrieb:
There is a draft at the front door seal

Most tests are therefore conducted at the front door.
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R.Hotzenplotz
17 Jul 2018 23:11
Is the blower door test always performed only after moving in, or when is the ideal time to carry it out?
K
Knallkörper
17 Jul 2018 23:27
Before the parts of the construction that are supposed to ensure airtightness become inaccessible. Otherwise, how should leaks be found and repaired? For example, drywall installation should not start before the blower door test, especially if there is a vapor barrier behind it. Doing this after moving in is at least unusual, I would say.
M
Müllerin
17 Jul 2018 23:29
After moving in, it's usually too late because any leaks or damaged areas would need to be reopened and repaired. You might then have to clean or paint again depending on the spot...