I have added a second bathroom and need to run the exhaust fan through the metal roof. I think most roof vents rely on shingles overlaping the vent flashing to avoid leaks. Since I'm working on a metal roof that does not work. How do I cut through the roof and install a new exhaust vent without creating a leak? I'd appreciate it if somone could direct me to instructions or a product suitable for this application. Thanks.
You need to go to your local lumberyard and see what they have. They make flexible flashing boots for metal roofs. Try to keep the vent towards the top of the roof if you can. Better if you could vent it out a gable end. You could also bend up a custom boot.
Thanks for the input. I will install near the top of the roof. I'm not sure if I can explain the situation any better other than to say that all of the interior ceilings, with one exception, run parallel to, just inches underneath, the roof line. The one exception is a roughly 10 x 10 x 10 foot storage space above the bathroom (located centrally in the house) which is where the exhaust fan is mounted. The ceiling/roof is directly overhead. There is no attic per se and no access to any gable ends or eaves. I will look for the flexible flashing boots for metal roofs, as you suggest. Do these elimnate the need to "overlap" the flashing with the roof? I don't want to have to pull up the roof just to install the vent unless that is the only way to avoid leaks. That would turn a four hour job into an ordeal. Thanks again.