Abandoned old vent stack in wall
#1
07-05-18, 06:29 PM
Abandoned old vent stack in wall
Hi Everyone,
I am new to the forum, so I apologize if these questions have already been asked.
Background: I just bought a 100-year-old house that has had several renovations. I started to smell sewer gas in a bathroom that was renovated a few years ago, so I called a plumber. The plumber said he found the pipes to the old bathroom in the crawlspace, but we cannot figure out where the old vent stack is. We don't see the vent stack coming out of the roof, so we assume the stack is in a wall. The plumber said the smell could be from the old stack, but he also suggested that the main sewer line, which is very old, needs to be replaced because it is not at the proper slope and therefore is not draining properly and potentially causing the smell. He also said he didn't think the vent stack was clogged.
1) Could the old vent stack be causing the sewer smell?
2) How do you find an abandoned old vent stack?
3) What should we do with the abandoned old vent stack? Should it be capped, removed, or what?
Thanks,
AJGreen
I am new to the forum, so I apologize if these questions have already been asked.
Background: I just bought a 100-year-old house that has had several renovations. I started to smell sewer gas in a bathroom that was renovated a few years ago, so I called a plumber. The plumber said he found the pipes to the old bathroom in the crawlspace, but we cannot figure out where the old vent stack is. We don't see the vent stack coming out of the roof, so we assume the stack is in a wall. The plumber said the smell could be from the old stack, but he also suggested that the main sewer line, which is very old, needs to be replaced because it is not at the proper slope and therefore is not draining properly and potentially causing the smell. He also said he didn't think the vent stack was clogged.
1) Could the old vent stack be causing the sewer smell?
2) How do you find an abandoned old vent stack?
3) What should we do with the abandoned old vent stack? Should it be capped, removed, or what?
Thanks,
AJGreen
#2
07-08-18, 06:42 PM
Many older houses had only one stack out the roof. The individual fixtures rarely have their own vents.
Sewer smells are often caused by water being sucked out of the fixture traps. Sometimes this is due to vents, but occasionally due to a shower or something that is infrequently used.
But to answer your questions specifically:
Yes, if there actually is an open vent in a wall or in the attic. It's possible, but unlikely unless the renovations were done really poorly.
Check the attic first. We've seen some posts here who had a vent stack into the attic, but never through the roof.
If you do actually have an abandoned stack, it should likely be extended up through the roof.
Unlikely. If it's not draining properly, you may end up with clogs, but there still shouldn't be any smell. Unless the pipes are actually cracked/broken. Which could be a possibility.
Sewer smells are often caused by water being sucked out of the fixture traps. Sometimes this is due to vents, but occasionally due to a shower or something that is infrequently used.
But to answer your questions specifically:
1) Could the old vent stack be causing the sewer smell?
2) How do you find an abandoned old vent stack?
3) What should we do with the abandoned old vent stack? Should it be capped, removed, or what?
the main sewer line, which is very old, needs to be replaced because it is not at the proper slope and therefore is not draining properly and potentially causing the smell.
#3
07-08-18, 07:24 PM
Member
Houses that old are always fun.
Could be many things
Drains under the sinks running down to the floor instead of out the wall with no APV vent?
That style drain was against code long ago because the traps could be sucked out allowing sewer gas in. unless someone added a APV vent.
Old steel plumbing that will leak at some point 100% of the time?
I agree the first place I'd be looking is in the attic, no one in there right mind would have busted out a likely plaster wall, taken the trouble to cut off the pipe. lifted out all that weight out the roof and left an open pipe inside the wall.
Could be many things
Drains under the sinks running down to the floor instead of out the wall with no APV vent?
That style drain was against code long ago because the traps could be sucked out allowing sewer gas in. unless someone added a APV vent.
Old steel plumbing that will leak at some point 100% of the time?
I agree the first place I'd be looking is in the attic, no one in there right mind would have busted out a likely plaster wall, taken the trouble to cut off the pipe. lifted out all that weight out the roof and left an open pipe inside the wall.
