How do you install a kitchen exhaust fan flue through a standing seam tin roof so it doesn't leak?

Standing seam roofs can be a pain to flash penetrations sometimes because, invariably, the penetration usually lands on one of the seams (Murphy's Law?).

My solution would be to have a local sheetmetal shop custom build a flashing for you. It may cost you a little bit, but not near as much as the damage you might incur down the road with a cobbled together leaky flashing.

If there is no sheetmetal shop nearby, you might contact the original supplier of the roofing for their recommendation or a lumber yard who sells the roofing product line.

If you do get a flashing and are installing it yourself, be sure you get clear instructions on how to cut into the roofing, how to set the flashing and how to fasten and weatherize it properly. Have all the right tools and safety gear for working on a roof.

Another way to seal a penatration through a metal roof is with a product called a deck tite pipe flashing system. This is a EPDM rubber boot that fits over and/or arount the penetration. It is installed with sealant and screws through the roofing and has semi rigid metal collar that can conform the the ribs of any roofing.

I purchase such products from a company called Dynamic Fastener.

First answer by Hammerbeam. Last edit by Tmattson. Contributor trust: 27 [recommend contributor]. Question popularity: 78 [recommend question]