Flashing on a hot tin roof

StanP said:

Hello everyone

I have a quick question about installing my chimney through a cathedral ceiling in my log cabin. I have a metal roof, and was wondering what you would use to attach the flashing to the metal roof. I believe high temperature silicon would be used around the chimney pipe, but I was wondering what you would use to attach the flashing. I guess the same silicon might work. Would you just put a bead around the edge of the flashing or would you cover the entire area where the roof and flashing are touching.?

thanks for the help. great site!

Stan

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Hi temp silicone around the pipe is fine. As far as the surface where the metal roof & flashing meet, I would not trust silicone.
Roof cement, even with fiber tape will crack due to both pcs of metal expanding & contracting.
I would go with a good urethane caulk. Set a good bead around just inside the perimeter of the flashing pan where it meets the roof.
If you want to be real sure, smear the entire roof surface where the flashing pan will cover it with the urethane caulk.
Then seal the edge of the flashing pan on all 4 edges. Finally seal the tops of the fasteners you use to secure the pan to the roof.

If you can get your hands on some EPDM (rubber roofing) flashing, that would work well also, & can be painted to match the roof color (with proper paint).
There is a few companies that make a peel & stick type roofing also. You could use that over the flashing pan & roof. Just make sure whatever you use, you clean the oil off the surface of the flashing top & underside, and also clean the roof surface real well. This will allow good bonding & sealing.

Rather glad you're not cleaning your chimney naked.

Hogwildz's got ya covered.

Buy the correct Flashing boot for a metal roof. They are red in color have a metal rim that will bend and high in price. But you just screw it down it will flex to fit the corrugation.