When using tapes and membranes, whoever does that needs to be trained well, and needs to have attention to detail. What I discovered from a recent Passive House retrofit project I was working on, is that people still think that if you cover it up, it’s going to be OK! But unfortunately for them, an air test never lies, so it’s really best to get it right the first time round. In this example, I had to go and remove all the battening to check that the membrane hadn’t been damaged – and in many cases it had.
Some typical things to check and watch out for are described here.