Roof Decking
CSI Division 07, Thermal and Moisture Protection
The wood sheathing layer installed directly over roof framing that shingles or other roofing material get fastened to, distinct from steel decking, which is a completely different material used in commercial structural floor and roof systems.
Why it matters
Roof decking has to be structurally sound for shingles to stay properly fastened and for the roof to perform at all. Water damage that gets past a failing roof covering often soaks into the decking underneath, causing it to go soft or spongy, a condition restoration crews specifically check for since it means more than just the surface shingles need replacing.
On a real project
During a roof replacement after storm damage, a restoration crew finds a section of roof decking that's gone soft and spongy from prior water intrusion, and replaces that section of decking entirely before installing new shingles over it.
Who this matters most to
A Restoration Project Manager checks the condition of roof decking during a storm-damage assessment, since decking that's deteriorated changes the scope of repair well beyond just the visible shingle damage.
Where this goes wrong
A roofing crew installs new shingles directly over decking that's already gone soft from prior water damage, without checking the decking's condition first. The new roof doesn't hold its fasteners properly, and the problem resurfaces as a leak within a relatively short time.