A nail pop is a roofing nail that has worked its way back up out of the roof deck. It lifts the shingle above it into a small bump, and sometimes pokes right through.
One or two pops are a quick repair. Rows of them across the roof point at the deck or at how the roof was nailed, and that is a bigger conversation.
What causes roof nail pops?
The wood under the shingles moving, and nails that were never seated right to begin with. Usually both.
- Deck movement. GAF’s technical bulletin on improperly driven nails says a nail left standing proud pops when the deck expands and contracts. The Asphalt Roofing Manufacturers Association (ARMA) says roof boards that get wet from rain or dew during the job take on moisture and move, that board decks swell and shrink unevenly, and that a poorly vented attic adds to it.
- Nails not driven flush. A nail gun set too light leaves the head sitting above the shingle. Set too hard, it cuts through. ARMA lists nails that are not flush among the causes of bumps and distortions on a roof.
- Short nails. Owens Corning wants every nail at least 3/4 inch into the wood deck, or through it by at least 1/4 inch. Trade sources say nails too short to grip the deck, common when new shingles go over old ones, back out sooner.
- High nails. A nail above the marked nailing strip can miss the shingle underneath. Trade sources tie this to shingles blowing off in wind.
Cold gets blamed too. We found no study that ties freezing weather to nail pops directly. What winter does bring is frost on the nail tips in a damp attic, which rusts them and drips when it melts.
Why do nail pops leak?
Because the nail pushes up into the shingle above it. GAF says a raised nail can lift that shingle off its sealant strip and can puncture it, and a puncture is a hole in the roof.
The lifted shingle has a second problem. Once it is unsealed, wind gets under it, and GAF says it is more likely to blow off.
Got a mark on the ceiling already? Read how to tell where a ceiling stain comes from.
How do I spot nail pops?
Look for small round bumps under the shingles, a shingle tab that will not lie flat, or a bright nail head catching the sun. Binoculars from the yard work.
The attic tells you more. Rusty nail tips poking through the roof boards are a sign of a ventilation problem, according to Air Vent, a vent maker, and frost on those tips in January means damp house air is reaching them.
Stay off the roof to look. A contractor can check each bump by hand.
What do shingle makers say about nailing?
Drive it flush and keep it inside the marked strip. Here is what two makers put in writing.
| Rule | What the maker says |
|---|---|
| Nail type | Owens Corning: galvanized steel, stainless steel or aluminum, at least 12 gauge shank and a 3/8 inch head (Duration instructions, September 2022) |
| Depth | Owens Corning: at least 3/4 inch into the wood deck, or through it by at least 1/4 inch |
| Where the nail goes | Owens Corning: inside the marked SureNail strip. GAF: on or between the painted lines of its StrikeZone, about 1.81 inches wide |
| How it is driven | ARMA: the correct length, fully driven and flush, without cutting into the shingle. GAF sorts bad nails into over-driven, under-driven and angled |
| How many | The model code calls for at least four nails per strip shingle. Some wind warranties need six |
| The deck | Owens Corning: at least 3/8 inch plywood or 7/16 inch OSB, kept dry before, during and after the job |
Owens Corning also says it is not responsible for problems that come from not following its instructions. For wind ratings and nail counts by brand, see which shingles hold up in Sioux Falls, and for the deck, what goes under the shingles.
Can nail pops be fixed, or do I need a new roof?
A few scattered pops get fixed. GAF’s repair: lift the shingle above, pull the bad nail, drive a new one in the right spot, and seal the old hole and the shingle above it with roof cement. Trade guides add that a nail that has backed out should be replaced, not hammered back down.
Many pops are a different story. ARMA says when shingles keep distorting, a professional should look for the root cause, including fasteners backing out of the deck and attic ventilation. Once that cause is fixed, the shingles go back flat, or new ones go on if the old ones are damaged.
That can mean deck work, since rotted boards get replaced before new shingles go on.
We found no reliable Sioux Falls price for nail pop repair. A contractor’s visit gives you the real number, and when a repair stops making sense helps with the bigger decision.
Who pays for nail pops: the roofer, the maker or insurance?
On a young roof, start with the roofer. Pops from nails that were set too high, too short or not flush are installation problems, and shingle makers do not cover installation problems.
Insurance is a long shot. Policy roof endorsements can leave out wear and tear and poor installation, and nail pops fall under one or the other unless a storm clearly caused them.
On a roof a few years old, call the company that put it on and ask what their workmanship warranty covers. Get the answer in writing.
Questions about nail pops
Are nail pops on a roof a big deal?
One or two are a small repair. Left alone they can puncture the shingle above or let it blow off, and many of them point to a deck or nailing problem.
What causes nail pops on a new roof?
Nails not driven flush, nails too short or set above the nailing strip, and roof boards that got wet during the job and moved.
Can I just hammer a popped nail back in?
Trade guides say to replace it instead. GAF’s repair is to pull it, drive a new nail in the right spot and seal the old hole with roof cement.
Do nail pops cause leaks?
They can. A raised nail can lift the shingle above off its seal or punch through it, and either one lets water in.
Does homeowners insurance cover nail pops?
Rarely. Policies can exclude wear and tear and poor installation, which is where most nail pops come from.
Get a quote
Tell us about the job, with a photo of the bumps, and a local roofing contractor will call, text or email to set up a visit. The quote is free.