Fastening plumbing vent flashings

Should plumbing vent flashings be nailed down at bottom edge?

I usually don’t call it out if the flashing is laying flat like that one. “Don’t be a pinhead” is my philosophy.

I agree some of these flashing shrink and tear at the nails … Roy

95% of the ones I see usually are nailed. I’m assuming that they’re nailed to avoid the potential for wind damage.

Thanks for the replies.


Always lightly pull up on the edge. If it moves up too easily recommend nails into the truss to prevent uplift. Sometimes they are fastened with glue. This is not a good idea but it is what it is.:smiley:

Typically with this type flashing, I dont report it, unless as Kevin stated, it is loose. Why introduce more nail holes that may eventually leak? Also, ‘wiggle’ the pipe itself to see if it is fastened securly. If not, it will loosen the flashing over time.

Yes, it should be nailed down so you get a roof leak!

It should also be sealed at the bottom so the water that gets in, can’t get out and leaks into the attic.

And the top should be on top of the shingles, sealed with mastic. :slight_smile:

Best You tube video on proper installation.

Looks to me he used steel nails on aluminum not a good thing ( ) .
Should be aluminum nails.
A saftey harness is a good idea too … Roy

Here in Port St. Lucie, FL we frequently have high wind events with wind-driven rain blowing in all directions, sideways and uphill.

Therefore, proper practice and best technique calls for placing the flashing over the pipe and directly onto a bed of roof cement on top of the felt. Then we in South Florida shingle over the entire flange up to the pipe, securing the shingles with roofing cement over the flange where a nail penetration is undesirable.




Marcel those pictures are not correct.
Look at the install video I just put on the MB.:frowning:

Great photos. But you never see it done like that around here.

Those photos came from this site;

And these are from the new CertainTeed Shingle Applicator’s Manual


You forgot the last image where they cut out the bottom section of the shingle to prevent water on the lower portion of the flashing.

Well, that is what I would do also.
Keep in mind that due to the variation of the shingle layout, the exposed portion of the boot flashing will vary. :slight_smile:

Wet stack or waste vent looks fine, as long as it is back caulked at the bottom of the flashing. Where it is cut was made for the projection.The noeprine flashing is OK to.
If the shingles are done right and cut tight to the vent stack them BOBS your uncle mate.:slight_smile:

I would like to see a cap on the vent. Stops rodents, tennis balls tree branchs and debris from entering the stack.
Still have to get use to ABS, plumbing or wet stack protrusions.

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Sounds like a movie.
I can hear whistling in the back ground.
Kevin are you playing tricks on me?:roll: