On Mon, 18 Aug 2008 09:25:59 -0700 (PDT), 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.


I've never heard of roofing nails backing out either. Unless somebody
was inside bounding the ends upward, I can't think of a backing out
mechanism, especially if the shingles are flat.