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wagonersa
Leak in exust pipe

My ceiling started to get a continuous drip about 2 weeks ago. I went up into my attic and noticed small drops of water coming off of my PVC exhaust pipe. Thinking it was coming in from the roof, I went out and bought roof sealant.
After sealing up the roof, I thought I had the problem taken care of. The next day of course it started to drip again.
I headed up into the attic and upon closer inspection it looked like there was a leak in between two connections of pipe. So I headed out to the local hardware store and asked what to do now. They recommend epoxy putty. Got that and put it around the pipe that was leaking (it did say it was waterproof). Once again I thought the problem was finished.
This morning the wife informed me that once again the ceiling was dripping water. Headed back up and the same spot were it was leaking between the pipe connections, and where I put the putty, a drip is forming again. Any ideas as to why? and how to stop it?

Thanks

Dobbs
Re: Leak in exust pipe

I'm still trying to imagine in my mind what a PVC "exhaust" pipe is doing up in the roof/attic--it may be better to just remove the pipe & seal the hole with roofing cement???---if you are active with a photo hosting site please post a photo or two of this to clarify what you have there.

Modern ways of joining or sealing PVC pipe are listed below; perhaps others have other suggestions as well.

http://www.youtube.com/watch?v=Zirp8vqApQc&feature=endscreen
http://www.youtube.com/watch?v=qh9YxXRVLFU&feature=endscreen

dj1
Re: Leak in exust pipe

A connection replacement is needed.

PVC is easy to work with, easy to cut with a hacksaw, easy to cement glue. Just cut off the main line before the connection and after the connection, go to the store and get new parts and re-do it. This time glue it tight, follow the instructions.

BTW, if this is a vent, why do you have a connection? also, what is the diameter of this pipe?

HoustonRemodeler
Re: Leak in exust pipe

If this is a straight section of pipe;

Cut it before and after the fitting. Install a coupling on one side and slide on a repair coupling on the other side. Install a new section of pipe. Slide down the repair coupling.

If this is at a fitting, please let us know.

Can you wiggle the pipes to see if this connection is loose?

HoustonRemodeler
Re: Leak in exust pipe

Also, vent pipes should be sloped as to drain themselves, the same as waste lines. Make sure the pipes are properly supported.

wagonersa
Re: Leak in exust pipe

Thanks for the answers. I was afraid I would have to replace the connection.

The leak is at a corner joint. I have a furnace and out of the furnace is the pipe it goes up into the attic, takes a left bend, runs horizontal for about 10 feet, then bends vertical up out of the attic. It is at the last bend that the leak is occurring.

So do i just cut right at the corner or do I need to go a little further down and up and replace some section of straight pipe as well?
Also what does properly supported pipes look like? All it really has is a black strap wrapped around a rafter holding it up

dj1
Re: Leak in exust pipe

With the new information you provided, I now have a question for you: is the water leak showing up OUTSIDE the pipe?

Can you post a photo via photobucket.com?

HoustonRemodeler
Re: Leak in exust pipe

You'll be cutting on either side of the elbow, installing 2 couplers, 2 sections of pipe and one elbo.

Properly supported pipe doesn't sag between supports and all drains / leans / tilts down hill towards the main drain (away from the sky) at least 1/4" per one foot of linear run.

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