I hope that's a good thing doing as you say I don't wanna be doing it a 3rd time To be fair iv read lots of other posts which say similar stuff just some talk about vapour barriers. Lucky for me the other half the building (the shed half) hasn't been boarded on the exterior wall so before hacking off the other one I'll probably do the other side first and see how I get on but I'm sure if I follow your advice it will be fine. Wish I had signed up on here first before doing it.Oh and that has got to be the first time I've ever read on here "I am thinking of doing what flynnyman says"