The wall conduct “Thermobox” demonstrates clearly higher tightness in comparison to other wall conducts tested. Both in the positive pressure measurement up to +60 Pa and in the negative pressure measurement at - 60 Pa, the wall conduct “Thermobox” was the only wall conduct tested to remain closed and airtight.
The airtightness achieved in the blower door test reduces the heat loss almost to zero when the extractor hood is switched off.The energetic quality is drastically improved, because the flap has the same high tightness in both directions (negative pressure and positive-pressure measurement).