Why are nails protruding through my roof?
In the attic: usually normal
Rows of nail points along the underside of the deck are a sign the roof was nailed correctly. Two things are worth noticing:
- Rust on the tips: points to humid attic air condensing on the cold metal, a ventilation issue.
- Dripping or frost on the tips in winter: the same condensation problem, more common in the mountains.
On the roof: nail pops
A nail pop is a fastener working its way up, lifting the shingle above it into a small bump or punching through it. Causes include:
- Deck movement: sheathing swells and shrinks with Georgia humidity and temperature swings, slowly pushing nails up.
- Sheathing nails that missed the rafters: they hold nothing and back out over time, pushing the shingles from below.
- Underdriven or crooked shingle nails left slightly raised at installation.
- Nails too short to grip the deck properly.
Why fix them
A raised nail keeps the shingle above from sealing, so wind can lift it, and the hole around the shank lets water follow the nail into the deck. Left alone, nail pops become leaks and blow-offs.
The fix
Lift the shingle carefully, pull the nail, drive a new one into solid wood beside the old hole, seal the old hole, and press the shingle back down. A few pops are a simple repair. Widespread pops usually mean a deck or installation problem that is best addressed at replacement, with the deck renailed to the framing. These are generally treated as wear or workmanship, not storm damage.
See common causes of roof leaks and roof ventilation basics.