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Lv_pa (Lv_pa)
Advanced Member
Username: Lv_pa

Post Number: 47
Registered: 05-2007
Posted on Monday, April 02, 2012 - 08:57 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Cpaulin-- Well, I already sent back the caps, but other than that I basically did what you suggested, I took off the caps and cut tabs around the top of the outer pipe and folded them down into the inner pipe.

I don't know how the caps would fit back on after I did this, as I seem to remember they fit inside the outer pipe. I'm sure with enough fiddling around there's some way to reattach them, but it didn't seem worth it so I just sent them back.
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Cpaulin (Cpaulin)
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Username: Cpaulin

Post Number: 7
Registered: 08-2006
Posted on Thursday, March 29, 2012 - 12:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Adding to what frost was saying:

Just remove the cap, peen the vent stack flashing inside the vent pipe, and replace the cap.

Voila, problem solved, outside looks the same, no sticky stuff necessary.


(Message edited by cpaulin on March 29, 2012)
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Lv_pa (Lv_pa)
Advanced Member
Username: Lv_pa

Post Number: 45
Registered: 05-2007
Posted on Thursday, February 23, 2012 - 02:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Thanks Frost. I'm still debating the best fix here but this gives me some more options. Thanks for the vid too.
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Frost (Frost)
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Username: Frost

Post Number: 7
Registered: 11-2011
Posted on Wednesday, February 22, 2012 - 05:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Great stuff expanding insulation From home depot.

Second don't pull it out bend the top of the pipe over to the inside of the pipe like you would a lead flashing.

Using a torch wrap a wet towel around the base so as to stop the heat from melting the lead. Second don't worry not enough methane for an explosion done it dozens of time. After copper glows for a second wipe jt don with a sopping wringing wet towel and it until bent again will be almost as soft as lead. And cut 2" tall that the vent pipe will fold inside of the stack. I make these vents all the time and it will work great for you no caulk. Watch a video on YouTube "copper pipe collar". And well you'll get it easy peasy.
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Lv_pa (Lv_pa)
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Username: Lv_pa

Post Number: 44
Registered: 05-2007
Posted on Wednesday, February 22, 2012 - 04:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Frost: Yeah, that's pretty much what I've been thinking, I need to get rid of the cap and put some kind of collar over the two pipes to cover the gap. I don't know how to do annealing, but if it involves a torch, I probably have to do it on the ground, as I don't want to risk igniting methane coming from the vent.

I didn't understand the bit about "squirts of great stuff", can you decode that for me?
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Frost (Frost)
New member
Username: Frost

Post Number: 6
Registered: 11-2011
Posted on Tuesday, February 21, 2012 - 10:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

if it were i, i would take off the cap and aneal the copper like 2 inches above your stack pipe, an fold it into the pipe...eliminating the cap and keeping a good pipe collar. although i wonder why so much heat escapes from around that pipe to cause the problem..you solution might be as easy as a few squirts of great stuff to be frank.
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Branden_wilson (Branden_wilson)
Senior Member
Username: Branden_wilson

Post Number: 109
Registered: 03-2008
Posted on Friday, February 17, 2012 - 12:10 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

wow very interesting. i have installed a couple of that style flashings. thankfully most of them are in warm climates but i know of at least one for sure up north. i'm going to have to look into it. thanks for pointing that out and doing such a good job at describing the problem!

REAL SLATER
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Lv_pa (Lv_pa)
Advanced Member
Username: Lv_pa

Post Number: 43
Registered: 05-2007
Posted on Thursday, February 16, 2012 - 08:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Yes, I called and e-mailed the Jenkins store. I haven't heard back yet. I'm hoping they'll do some sort of exchange with the regular flashings.

I guess it's possible I could somehow use a coupling or seal the gap between the inner and outer pipe. There's about 1/2" to 1" of play in that gap. It seems like that's too much to tar or caulk, but not enough to use a fitting. I don't really know how to do that. Plus, I already cut off the bottom part of the pipe flashings, because that's what the video tells you to do when you have a 12:12 or greater roof slope.
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Chris (Chris)
Senior Member
Username: Chris

Post Number: 133
Registered: 09-2009
Posted on Wednesday, February 15, 2012 - 10:36 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

very interesting.
so based on your field test it appears that the pipe should not be used as a sleeve, but rather, it must be joined to the existing pipe below the roof deck using a fernco or similar type coupling?

jenkins carries many many products on his website....did you call them right away to let them know?
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Lv_pa (Lv_pa)
Advanced Member
Username: Lv_pa

Post Number: 42
Registered: 05-2007
Posted on Wednesday, February 15, 2012 - 08:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

The other pipe appears to be currently unused-- there is no sewer odor coming from it. (The one which is leaking does have a sewer smell.)

I flashed and slated around the unused one to be on the safe side. But if at some point a plumber comes along and says hey, there's a convenient unused vent pipe, I'll just hook into that, I'll probably have the same problem there as well.
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Old_school (Old_school)
Senior Member
Username: Old_school

Post Number: 787
Registered: 01-2009
Posted on Wednesday, February 15, 2012 - 04:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Just on one pipe?
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Lv_pa (Lv_pa)
Advanced Member
Username: Lv_pa

Post Number: 41
Registered: 05-2007
Posted on Wednesday, February 15, 2012 - 02:13 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

So it was raining last night and this morning, and I noticed leaks around one of my brand new "German Copper Vent Pipe Flashings" from the Jenkins store. After investigating, I concluded that the leaks were not from rain but from condensation. I went up to the roof and pulled off the cap, and sure enough, the underside of the cap was dripping wet.

So apparently warm humid air is coming up through the vent pipe, hitting the underside of the cap, and water is condensing there, and dripping around to the perimeter of the cap, and then down through the gap between the vent pipe and the flashing pipe.

This appears to me to be a fatal design flaw in this product. I would think everyone who uses this product is going to have the same problem and I can't believe I'm the first to have noticed it.

I should have gotten the regular pipe flashings with neoprene collars instead. So now I have to figure out if I should ditch the German ones and get regular ones, or should I just get rid of the caps, cut off a few inches of the flashing pipes, and put a neoprene collar on the top of the vent pipe? It would look dumb but at this point, if it keeps out the rain and condensation, I'm not going to complain.

What do you guys think?

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