I want to add a roof type kitchen vent. I have a GE NoiseMaker microwave
mounted on top of my gas cooking range. It can vent out. I have decided
to put in ducting going out through the sheetrock ceiling and then out
of the roof. Two holes have to be made:

6inch round duct beng used.

1. 6inch hole in the sheet rock ceiling. (piece of cake .. easy)

2. a hole in the roof directly (about 10 feet) above the ceiling. Roof
is 5/8ich plywood with roofing felt with standard 3-tab asphalt
shingles. Here a vent has to be installed with damper.

Can anyone provide some tips for the 2nd step to prevent leaking after
the vent is installed. Any links to good damper and flashing systems.
Any instruction of how to cut the shngles and any overlapping methods
for the flashing on the vent. Any glues and caulks?

THis vill be done by a contractor.. he is good but he does not have
experience with cutting through the roof and making a vent hole or
hanlding shingles. But with enough care and reading I am sure we can do it.

Its hard to find contractors here that will just handle this as oppsed
to redoing the wole kitchen.

Any help appreciated!!