Concentric vent flashing options?


#1

I am replacing my roof in the Pacific NW and was wondering what the best option for flashing my furnace vent would be? Its a concentric PVC vent so nothing fancy, but i haven’t been able to find a good example of flashing for that other than the typical galvanized plate with a rubber gasket. I’ve heard those never last as long as the rest of the roof and i’m hoping to avoid a leak in 10 years. The cap on the vent makes it impossible to just slip a new collar over it. I’m planning to strop by the roofing supply place today but thought i’d toss it out here first. Thanks!

EDIT: My furnace pipe is concentric, so i cant just cut it and couple it back together. I ended up talking to the local ABC Roofing shop and picked up a supposed lifetime alternative to the usual Oatey pipe flashing. I would post a pic but my account was put on hold 4 days ago and i cant post anything else.


#2

I havent seen pvc in conjunction with a furnace vent before.
A picture would be be immediately helpful
And lots of ideas will come.

Oh you really mean the plumbing vent…
I use the galvanized base with the rubber gasket
Double the gasket for full security.
I used lead only my first 18 years of roofing.
Then i faced inspections and failed a final inspection because the squirrels chewed the top off.
Realized it was a much bigger problem than i had previously thought.
Material last a lifetime but cant make it past the squirrels. Its like candy to them.


#3

There are other style pipe collars/ boots out there that work for plumbing vents , but as far as I know the only thing that will work for a furnace vent with a cap is the cheap style with the rubber gasket.

Easy way to install a new one if the cap on top is glued, 50% of the time they arnt glued, is cut the pipe, install a new pipe flashing, then glue a coupling in.