Traditional build here and have given some thought to airtightness. Internal wet plaster is effectively going to create my airtightness. I appreciate the wall/ceiling junction can crack and compromise the airtightness. The issue I have is that through choice in our bedroom block (circa 5.5m x 21m) we will have 34 spotlights. My question is therefore is it worth spending time on airtight membrane to then puncture it in so many places?
I will do windows and doors with tape.
Please don't send me to the firing squad.