DerbyDad03 wrote:
I just got a call from a roofer who looked at my roof and prepared an
estimate. Some of you may recall that I had what I called “nail pops”
pushing through the tabs of my 20 YO asphalt shingles.

All of the following statements are "according to him"

- There is no such thing as a "nail pop".
- Ring shank roofing nails cannot back themselves out due to
contraction-expansion cycles or any other reason.
- In my entire career, I have never seen a roofing nail back itself
out and I have done hundreds of roofs for all of the high-end builders
in the area. They wouldn't use me if I didn’t know my stuff.
- The reason your house has nail heads popping through the shingles is
because these were "high nails" - nails that were never properly set
by the contractor who installed the roof. The compressor didn't seat
the nails completely and the roofer was too lazy to grab a hammer and
pound them down.
- I will hammer all of your high nails down and add a second layer
over the original
- I will guarantee, in writing, that the original nails will not back
themselves out and damage the new roof.

So what's the deal? Can roofing nails back themselves out as I have
heard from many sources or does this guy know the "real story"?

They can (and do) and many roofing nails aren't ring-shank, anyway.

I can show you pictures of siding nails (ring shank as well as straight)
that over the years have worked themselves 1-2 _inches_ out of 80+ yr
old first growth yellow pine studs (that can't drive a nail into easily
at all owing to how hard they are)...

He's blowing smoke on most of the points. The only point on which I
would give him full credit is that it is possible there were high nails
left originally...

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