I am having a second storey addition added to my home. In order to match the the "standing seam" roof of another older section of our 80 year old home, I will be using a metal roof, with wide ridges. Is it acceptable to just "strap" underneath or should the roof be "sheathed" with plywood? The roof will have a 10:12 pitch.
Answer:
Sub-structure will depend on the manufacturer's instructions. All of them have standards and in order to retain the warranty, you'll have to follow their instructions quite to the letter.
