"Norminn" wrote in message
...

We helped a friend find the source of water running down a ceiling light
fixture. Popped plywood deck, not real obvious. In place of your plastic
and towels, lay newspaper over the plastic, wait for the next rain, and
check where the newspaper gets wet. Should be more visible. That and
paper towels is how I check for toilet leak ) Then, look above and next
to, where water might traverse a rafter before it drips. Any tiny bulges
where shingles and/or deck have lifted?

I was able to find what I believe is the spot. Just to the left of the
vent hood,
one section of sheathing board (i've got the tongue/groove kind) has split
somewhat
and a knot in the wood has fallen out. It is right from here that the water
drips.
The roofer commented its very common to have slight dips and peaks with
tongue/groove
sheathing as warping is pretty normal. There are no noticeablely huge dips
or warps tho.

Its actually interesting - there are intermittent spots on the roof where a
shingle has kind of
curled or blistered, and then a 10x10 area that is picture perfect. Then
another one somewhere
else....

Its pretty clear that the flashing around the vent hood is pooched. I'm
thinking that
when the roofer comes back, I'll just have him install a fresh vent for me,
something
a little taller. (sick of not using the fan cause its submerged in snow)
Though its interesting
since the roofer did pay attention to that particular hood, I can't really
tell if he hit the left
side or not.

Did you have a lot of wind when leaks occurred? Wind driving rain under
vent hood? Ice dams just previous? Clogged gutters?

No wind, gutters clear and perfectly clean. I had an ice dam in the
relative area,
but a year previous Below the vent hood actually, didn't realize the
low-slung
vent hood was melting snow that had submerged it...melt ran down and you
know the rest.