Joining Sewer Vents

Hi all.
In the attic of my new house I have two PVC sewer vent pipes that come up from the floorboards. One of them is run completely through the roof. The other terminates about two feet up from the floor into the attic. Would it be feasible for me to put an elbow onto this pipe, extend it over and join it with the pipe that goes through the roof. I would like to avoid putting another hole in my roof for obvious reasons. I'm not sure about the codes in my area, but I imagine that this would not be a problem. I would appreciate opinions.
Thanks,
Scott
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Lance Uppercut wrote:

Looks like the builder "forgot" to finish the job. (Might want to verify somehow that this pipe is actually a sewer vent. Listen at the opening for running water when flushing, etc.)
Yes, should be fine to connect them as long as the existing one thru roof is full size (4"). Slope the horizontal part of the extension so that it rises toward the vent you'll be connecting into.
Jim
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I don't think so. I'm not a plumber, but I see houses with 5 and 7 vent pipes in the roof. If the builder could save roofer costs by having the plumber joining all the vents (lesspenetratyions to seal), I think they would. Any plumbers out there...agree, disagree?

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If they're both really sewer-vent stacks, then last time I checked, you could connect them. (subject to some rules involving flood-levels of connected fixtures that aren't likely to affect you in an attic.) Are you sure that's what they are, though? It would really suck to find out after the fact that one of them's actually venting your laundryroom, or a bathroom.
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On 16 Dec 2003 10:12:03 -0800, snipped-for-privacy@comcast.net (Lance Uppercut) wrote:

I'm a retired plumber. The answer is YES. Be sure that is a vent though. I'd assume it would stink in your attic. But it could be an air vent from a fan or dryer vent, or ?????
Be sure it is a sewer vent. If it is, use the SAME size pipe, and use a slight upward pitch to the other stack. You dont need much pitch, but you dont want it going downward.
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Thanks for all of the replies.
The fine gentlemen that lived in the house before me was a plumber, just not a very good one. I assume that he added the vent that terminates in the attic for one reason or another when he remodeled the bathroom. I had a pumber out months ago for another reason and showed him the pipe. He had me flush the toilet and turn on the sinks in the bathroom directly below where the pipe enters the floor of the attic while he listened at the open end of the pipe. We determined that it is a vent for that bathroom. Am I wrong in labeling this a sewer vent? The pipe that terminates is 2 inches thick while the main stack is 4 inches. They are around 6 feet apart and I could angle the connection upward. Do they make connections for 2 inches going into 4 inches? I guess I'll have to go wander around Home Depot for an hour or two : )
I also have another vent that I found for a bathroom in the basement. It terminates right below the ceiling in the laundry room in my basement. Again, there are no bad odors present. This one has a filter on the top of it. I showed it to the same plumber that was in my attic and he told me that the filter just stopped air from going back into the vent. He also told me that he did not think that this was a problem. I disagreed. Why would anyone want to vent inside their house? Granted I am no plumber, but this just seemed stupid. Since most of the people that applied to my original thread are plumbers, I would appreciate you comments on this situation as well.
Thanks,
Scott

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(Lance

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Scott
The vents sound like that they are to allow air to enter and exit so the p traps will not loose any water in them as they will gurgle as water flows. The tolit bowl will also have a vent just for this purpose.
For the 4" to 2" adapter there is such and will be found in the area of the sewer line and tolet flanges etc. Just ask for one of the HD employees to assist and they will put it together for you.
Joining the two pipe ends to the sewer line willnot hurt anything but will not help either.
Think of the two pipes as an equlizer for the sewer as the estuation tubes do for your ears to keep the pressure inside the same as the outside.
C.

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snipped-for-privacy@usenet.com wrote:

roof the vents from three places were joined together exactly as described.
But make sure it is a plumbing vent! Terry.
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