I have a shake roof that is starting to leak.I plan to replace the roof with metal as we are in a high fire zone.The roof is a built up roof of 2x6 planks with tar paper, 2in. of foam,strapping and then the shakes.Can I strap over the shakes then attach metal to the stapping? The second option is to use 2x2 then add 1 1/2 in. of addtional foam followed by 1x4 horizontal strapping and the metal. I'm looking to retain the shake insulation and avoid costly removal
Answer:
I'm afraid the shakes will have to come off. Your system of adding insulation would leave a gap between two layers of insulation and that is not good. Strapping over shakes may cause you more problems than you want to put up with too.