I intend to build a uPVC conservatory onto the back of the rear of our semi. It needs planning permission because it is 4m deep.
One side wall of the conservatory will be adjacant to the 7' high party-wall wall that runs the length of the garden, so it won't get any sun. If I use a standard uPVC panel it will lose a lot of heat. I could build a cavity brick/block wall instead which would solve the insulation problem, but it would make the conservatory considerably narrower.
Is there a thin walling material, maybe 2" or 3" thick, that has high insulation properties, and that might satisfy planning, that I could use instead?
Thanks
Tony