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Greg Frazier
06-01-2009, 02:10 PM
Saw this on a roof today. They are way below 6 inches height. I don't tell my clients how to fix things but just for my curiosity, how would you fix this? There is no access to the pipes from inside the house without tearing out walls. I can envision removing the vent jack and hauling a welder and extra pipe sections up there. But....maybe there's a better way? And who would do it? A plumber or a roofer?

Gunnar Alquist
06-01-2009, 02:35 PM
Saw this on a roof today. They are way below 6 inches height. I don't tell my clients how to fix things but just for my curiosity, how would you fix this? There is no access to the pipes from inside the house without tearing out walls. I can envision removing the vent jack and hauling a welder and extra pipe sections up there. But....maybe there's a better way? And who would do it? A plumber or a roofer?

Greg,

Mobile home?

Since this is part of the plumbing system, I would choose...

Ted Menelly
06-01-2009, 02:38 PM
I would have the roofer do the plumbing cause he won't get the reshingle around the plumbing right and the plumber do the roofing cause he won't (and didn't) get the plumbing right.

Greg Frazier
06-01-2009, 03:06 PM
This was a single family home. The short vent stacks were above a dormer that had been added a long time ago when creating a bathroom upstairs.

Jerry Peck
06-01-2009, 05:12 PM
The simple fix (when accessible) is to cut the vent off in the attic, then add the necessary length piece on to achieve the required height, and it is only 6" when no snow load is present, otherwise it is 6" above anticipated snow load depth (as I recall).

With PVC, it is a simply cut, glue on a coupling, then stick the new longer piece up through the flashing and pull it down into the coupling, gluing it in place.

With cast iron, the process is similar, but cutting is harder, then use a hubless coupling to connect the new piece to the old piece (and the new piece can be PVC connected to old cast iron).

Brent Crouse
06-01-2009, 05:40 PM
Where is the 6" to be measured from? From the top of the boot, I assume.

Jerry Peck
06-01-2009, 06:05 PM
Where is the 6" to be measured from? From the top of the boot, I assume.

The top of the roof covering, in the photo that would be from the top of the shingles.

Not all flashings are like those, those kind of sorta raise the flat level higher and would make sense to measure from the top of the flashing, but the code, being minimum, only addresses above the roof covering.

Brent Crouse
06-01-2009, 06:44 PM
Jerry,

I was thinking about that option, but thought that would leave it a little "gray". Could depend on whether you measured on the high side, low side, or in the middle.

Jerry Peck
06-01-2009, 06:53 PM
I was thinking about that option, but thought that would leave it a little "gray". Could depend on whether you measured on the high side, low side, or in the middle.


Brent,

No gray in there.

That is the "minimum" height ... which means measuring *the shortest side* for height (on sloped roofs that would be the high side).

If you measured the tallest side as 6", the shortest side would not meet 6" "minimum" height, right? ;)

Got to not be trapped in that box when thinking about things ... :) :cool: