Can someone direct me to a website that gives you information on what I need to do exactly to insulate my pitched roof. I have 20 sheets of 50mm kingspan to put between the roof rafters. I have recently had a new roof fitted along with vent 3 underfelt. Do I need to install the kingspan between the rafters leaving a small air gap because of my vent 3 felt or does it still need to be 50mm gap. If so once the kingspan is between the rafters do I also need a foil quilt as extra insulation over the top of the rafters as well and then cross battan the foil.
Any advice would be greatly appreciated.
Any advice would be greatly appreciated.