The roof decking is definitely the layer of plywood or O.S.B. nailed to your trusses or rafters. Roof decking is typically seven/16” and is available in four’x8’ sheets. In the event you’re tearing off old roofing, the roofer can try to find problems that should be fixed once the deck https://digitalbizgenius.com/top-5-roofing-contractors-for-joliet-il-expert-services-for-your-home/