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Discussion Starter · #1 · (Edited)
The roof flashing a roofer installed for all the vent pipes on a new composite shingles roof install were all all-metal roof flashing.

Not knowledgeable in this, I wonder what type of rain collar would work with all-metal roof flashing. I looked up on Youtube and couldn't find any videos on all-metal roof flashing install except for chimney vent.

I put in an Oatey14206 rain collar over a 2" PVC HVAC vent pipe.

The all-metal roof flashing is larger in diameter than the PVC pipe. So there's around a 3/4" gap between the 2" PVC pipe and the roof flashing.

The Oatey14206 rain collar has an inner lip, but it hits right along the top edge of the all-metal roof flashing. So the rain collar stands a bit above the top of the all-metal roof flashing.

Tire Wheel Automotive tire Automotive design Tread


The roofer uses Wilmar rain collar, which doesn't have the inner lip like the Oatey rain collar. It fits well with the all-metal roof flashing and it covers the gap between the vent pipe and the metal roof flashing. But the Wilmar rain collar's material seems to be less strong.



Is the Wilmar rain collar the right kind of collar to use for vent pipes working with all-metal roof flashing, or there is another rain collar that would also work with all-metal roof flashing?

Thanks.
 

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Naildriver
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Usually on a metal roof a malleable ringed boot is installed and the ring is secured with roofing screws all around, too account for the aberrations of the humps and valleys.

 

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Discussion Starter · #3 · (Edited)
Sorry I meant the roof jack/flashing that is all-metal, not the roof.

Similar look to this one:


The roofer already put this kind of all-metal roof jack for all the vent pipes, including the HVAC PVC vent pipes.


Would only a specific kind of rain collar fit this metal roof jack properly?

Thanks.
 

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Discussion Starter · #4 · (Edited)
Here are some photos.


Wilmar rain collar on a metal flashing (no boot):

Sky Cloud Window Tree Gas


The Wilmar rain collar seems to fit nicely, and so the gap between the PVC vent pipe and the flashing is not exposed to the outside.


Oatey 14206 rain collar (with inner lip):
Tire Wheel Automotive design Automotive tire Tread


Installed on HVAC PVC inlet vent pipe, the flashing is a metal-only flashing (no boot):

Since the inner lip of the Oatey rain collar sits on the top edge of the metal flashing, I can see a slight gap (circled) exposed to the outside,

where rain water can potentially slip into the gap between the PVC vent pipe and the metal roof flashing.

Road surface Cone Composite material Gas Concrete





Sky Cloud Chimney Composite material Gas




Is there an Oatey rain collar that fits better similarly like the Wilmar rain collar on the metal (no boot) flashing?

Thanks.
 

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Naildriver
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Discussion Starter · #7 · (Edited)
I called Oatey customer support. They don't carry a rain collar without the inner lip.

I made the rain collar fit better

by cutting away bulk of the inner lip on the underside of the rain collar. It's a crude fix, but the rain collar fit much better afterward.


If anyone knows a better fitting rain collar let me know.


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Discussion Starter · #8 ·
I call Oatey. They said rain collars are supposed to be used as a secondary seal over an existing roof flashing that already has a built-in rubber boot.

Obviously, with a plain metal roof flashing that has no built-in rubber boot on the flashing, there's no primary seal over the pipe--without adding a rain collar,


I have a very basic question then:

is it wrong to use a plain, no-boot, plain metal roof flashing?


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Gas Composite material Tints and shades Cylinder Electric blue


Improve the primary seal between metal cone and the pipe.
It look like the primary seal is no seal at all.
Many people would just caulk this. You can use a black colored caulk like DAP Dynaflex 230 in black. Or paint it black after a caulk job.
First pull up the rubber collar to make room to work.
You want a decent strong totally guaranteed fast waterproof fix,
smear on Loctite PL poly construction adhesive, it will work great and be a permanent seal.
You can also mix some PL Poly construction adhesive with sawdust or even any black colored dust like charcoal and smear it over the joint between the metal and the pipe if the area gap is really huge and wide to fill. Can even stuff it with wadded paper towel to support the glue till it cures. Paint it black or leave it tan colored. I have found many uses for that glue.
LOCTITE PL Premium 10 fl. oz. Polyurethane Construction Adhesive 1390595 - The Home Depot
 
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