Roof deck attachment
What is measured
Roof deck attachment describes how the sheathing is fastened to the trusses or rafters. The form separates wood-deck fastening by fastener and spacing: 8d nails at 6 in. edge/6 in. field, 8d at 6 in./12 in., 8d at 12 in./12 in., 6d nails, staples, and other. Edge spacing is measured along panel edges; field spacing is within the panel. Nails must penetrate the sheathing and engage the framing.
How to verify
In the attic, locate a representative panel, measure nail spacing at an edge and in the field, and photograph the tape against the fasteners. If the roof covering is being replaced, verify from the top before re-covering. Do not infer spacing from one nail.
Worked example
You measure 6 in. between nails along a panel edge but 12 in. in the field. The correct category is 8d at 6 in./12 in., not 6 in./6 in. The weaker field spacing controls because the form asks for the actual attachment pattern, not the best edge.
Traps
- Measuring only the field or only the edge.
- Calling staples “8d nails.”
- Assuming 6 in./6 in. because the house is new.
- Failing to photograph the tape measure with the nails.