Today’s work on the air tightness identified a significant leak under the balcony which might account for the leakage being over the Passivhaus limit. I’m going to reserve judgement until I see the results of the next test, since I’ve been told before that there was just one more leak to fix…

Unfortunately, to get access to the underside of the balcony means removing the ceiling at the western end of the ground floor Open Plan room, which will need some very careful work to patch the plaster without a visible join. Of course, that is the one ceiling that is properly painted.

To put things into perspective, the house is roughly 10 times more air tight than required by UK Building Regulations, but still twice as leaky as demanded by the Passivhaus standard.