Q & A - Plywood Roof Decking Not Nailed Properly

Why is my plywood up off the roof deck?

Jason asked, "I just got my roof done. They needed to replace some plywood around the edges. The old plywood sits mostly flat at the edges. The edges of the new plywood are not flat in places. In some places, the plywood is raised a quarter-inch and in one place it’s half an inch. Is this a problem? I was told mice can not get in there because the bottom layer of plywood is sealed. But what about ice damming? (I live up north)."

The picture in this video was provided by Jason. You can see the edge of the plywood is not only raised but was left unprotected. A metal drip edge should have been used on the new roof. { shown by the black lines, I added } Drip edge metal comes in different dimensions, I would have used a 2×2 inch x 10 foot. There is most likely a reason the plywood is high here and it should be looked at and the sheeting repaired and nailed correctly. This all should have been done prior to the shingle application.

A review of the manufacturer's website should provide you with PDF drawings of proper shingle application and of drip edge. The video helps explain this better.

Have a question? AskARoofer.

Find your local roofing contractor in the RoofersCoffeeShop® Contractor Directory.