Nails directly under butt joints

Hi.  I hope I've to the right place for some practical advice.  I'm having a roof done.  During a work break, just for fun I went up the ladder to have a casual look at the job in progress.   Almost immedietaly I noticed a nail _directly_ under a butt joint - see attachement.   (The shingles had not yet stuck together, so the nail was visible from the angle I was at.)   This seemed unusual to me - "can't that leak ?"   And this was from just inspecting a small portion of the roof that I could see from the top of the ladder (I did not get up on the roof).

From other perusing on this forum it seems nails under the butt joint are indeed suspectible to leakage.   I'd really appreciate any constructive advice about how to deal with this now with my roofer.   The job is pretty much done now.   Should I ask him to inspect each of the butt joints, and remove any nails and seal them with something ?  (not sure if that is practical).

If it helps, my roof is somewhere between 7/12 and 8/12.

Hi Alfreds,

In my opinion, this can a serious problem since the possibility of leaks is very real. Here's some relevant info from a roofing company in Austin that I work for:

"some roofers may leave a vestigial nail on the shingle and apply another layer of shingles on top. This is a big issue, since the top of the nail will raise and in practice deform the upper layer of shingle, which leaves the roof open to leaks. To ensure a tight fit, nails should be placed no more than 4 to 5 inches from the shingle joint, and preferably only on the nailer strip."

Hope this helps,
Rick