I put a metal roof on mine but I knew how the moisture builds up on it because of sitting in a deer blind, one year, with a metal roof and getting wet from the moisture falling on me. So, I put down a thick OSB panel or plyboard, on the roof of my coop and then put down some black roofing paper over that, to keep the moisture from rotting the wood, over time. Then I put the sheet metal on. My suggestion is to remove the sheet metal and do it the way I did. Its the only permanent solution, in my book.