Hi, a window installer wants me to have replacement window fitted in existing space, then fill the gaps with foam and cover with finishing trims. This is instead of the recess being chopped out. He says it will save me money on a plasterer, which I accept, but is he just trying to make the job easier for himself? I guess the new window might be a fraction bigger if plaster was chopped out but that might not make much difference to cost. It's replacement of a standard uPVC window with a uPVC sliding sash window if that is of any significance (we are now included in a conservation area).
