Roof Jack on Metal Shed (one sided) Type Roof?

[djhcatony]

Hi folks,

Did some forum searching for discussions about installing a roof jack on metal shed roof but couldn't find quite the clarification a simpleton like me needs. If I have a "one" sided roof jack and a metal roof, do I cut the hole and push the jack up from below to mount or lay over top of the roof. My sense was that I would mount it on top of the surface of the roof and use the compliant gasket like material you would use under flashing to seal the jack but somewhere I saw a discussion where it was mounted with the jack's flashing underneath the roof surface. Hope this is making sense! Can anyone provide a little guidance or link to other help? Thanks!!

Dan

[GeneralStark]

With metal roofing. the roof jack should be mounted to the sub-roofing material at the top of the jack/flashing. Then the metal roofing overlaps the jack to a couple inches from the bottom of the jack/flashing. Then, the jack/flashing overlaps the lower section of roofing so water drips off the flashing and down the metal roofing. Here is a photo that may help. It is necessary to cut the roofing and fit it around the jack/flashing. You should have two pieces of roofing, one above and one below, with the upper piece overlapping the lower piece.

10351

[OCHTO]

The outfit I bought my steel roof from fabricates the steel at their shop so I bought a flat piece of steel the same color as my roof 3 ft. long. My chimney exits my roof within 3 ft of the peak and I put the flat piece of steel under the ridge cap and over the top of the chimney jack calking the top of the roof ribs under it first. Simple, looks good and I'm confident it will not leak.

[djhcatony]

Thanks to you both. I know exactly where I need to focus my efforts to get the stack up.
Dan