It’s the part of the roof that gets even less attention than the roof. Hard to notice or even see in many cases, the job of the roofing deck is to hold up the thing that keeps everything dry. Not a big deal — unless it has suffered years of neglect and abuse.
If the roofing is in bad shape, it doesn’t bode well for the decking. Roofing damage is easy enough to assess, but figuring out how bad a deck is before the tear-off is a complex equation. And if one spot is bad, who knows what shape other sections of the roof might be in. A bad deck can create the biggest hole of all — one that more than water can enter.