Hi. I'm hoping to get internal insualtion on two adjacent external walls. The issue is that on one of the walls we have a window right up to the edge of the wall. We are probably replacing the window so could look at making it smaller in width to allow the internal insulation to attach to some wall not window. It would be easier to keep same size window though. Could the insulation finish just before the window or would that defeat the whole point to have a gap? We are on a budget, so the cheapest options preferred. Any thoughts or ideas very much appreciated. Thanks!