DIY Home Improvement Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
Hello all,
Can anyone please answer which roof vent I need for this pretty flat EPDM rubber roof application if either of these is the correct one?
I live in South East PA and we do get some snow in the winter at times.
Can anyone help with telling me how to go about installing one of these on this rubber roof so I don't get any leaks? I will be installing a bathroom exhaust fan and light and this is the only place I have to duct it to.
Any help is appreciated.
Thank you
 

Attachments

·
Super Moderator
Joined
·
13,289 Posts
My EPDM experience is limited but you may be able to find a vent that you can use in conjunction with something like this. https://www.jm.com/content/dam/jm/g...8504_JMEPDMPeelStickPourableSealerpockets.pdf

I'd suggest going to some of the EPDM manufactures websites and look through the accessory pages.

You could also just go to one of the bigger EPDM roofing companies near you, tell them what your doing and just buy what you need from them.
 

·
Registered
Joined
·
7,880 Posts
https://www.primexvents.com/products/wall-caps/


It is plastic but has a draft door that's flat against the body. Cheap metal doors don't work well. Use pvc primer and outdoor paint which should protect and give it longer life.


Neither for me. First is too low to the roof and I had fair bit of leak through the cap during hard pouring rain. Water bounced off the shingles and came through the draft door. It was a cheap cap, though, but I haven't found anything better. Box hardware stores don't stock good quality caps. Second is higher off the roof but search says no draft door. This will bring in too much cold air.


So I would make a pvc or galvanized metal duct with a bend and connect the cap to it. With primex vents, the body needs to be tilted a little so the door will sit, or the door will hang open.


Then use roof vent flashing and eternabond tape to seal. Search, but I think eternabond is compatible with epdm roof. EPDM suppliers also should have repair strips and such but epdm roof has a history of adhesive fails along the seams. I think they use some kind of special seam tape now.


Regardless of your sealing choice, use several strips to make a wide seal. Even if the edges fail, you'll have more seal surface.
 

·
Hammered Thumb
Joined
·
3,991 Posts
Those are the basic 2 types of vents you can use, each has variations.

Low profile box vent: that will require a roof curb built up, regardless if you use a higher profile one (gooseneck style may be too open). You can use a prefab sheetmetal curb or build one yourself. Requires installing EPDM to flash the entirety.

'Stand' vent: simple method is to put a self-adhered EPDM boot down over top (cap removes to allow this). Can also use other method of installing EPDM strips to flash the penetration.

You can get the self-adhered EPDM products at the big box, make sure you get the Xylene primer and scrubber.

_________________________

The bigger thing I noticed, your drip edge is raised above the flat roof? So is there an interior roof drain so the flat roof holds the water in?
 

·
Registered
Joined
·
4 Posts
Discussion Starter · #5 ·
No to your question about the raised drip edge along the edge 3onthetree, there is a slight slope (towards bottom of the picture) that the whole rubber section leans towards.
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top