You found and treated a symptom, but you have not found the
problem. The water should not ever have been under the shingle.
You either have a bad flashing or a bad valley installation in the
area. The one other thing that occurs to me is that you do not
have enough pitch on the roof to use composition shingles. Most
manufacturers require 3 in 12 minimum.




(top posted for your convenience)
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Keep the whole world singing . . . .
DanG (remove the sevens)




"Mikepier" wrote in message
ups.com...
Last week I posted a problem with finding a roof leak. Well I
managed
to get up on the roof a few days ago with a water hose, and I
aimed it
right at where it was leaking in the attic. Sure enough, when I
went
into the attic I saw water dripping, so at least I found it
rightaway,
as opposed to the water traveling from another spot.
But even so, when I looked at the spot on the roof, I could not
see any
damage. I noticed that the edges of the shingles were glued
down.
Anotherwords the manufacturer had put a thin layer of roof
cement under
the edges so it would seal by itself in the sun.
So I carefully lift the edges breaking the seal, and then water
came
out. I guess the water was somehow entering the sides and being
trapped
under the shingle and making its way up to the nail under it. I
did
this to a few shingles on my roof and noticed the same thing,
water
coming out from underneath. So I took some roofing cement and
with a
putty knife managed to cover the nails under the shingles in the
spot
of the leak. Last night I went to check for leaks during the
rainstorm
we had, so far no leaks.
But has anyone ever heard of this problem? Why are the edges
sealed in
the first place?