I'd like to plumb a new 1/2 bath on our 1st floor, directly beneath an existing 2nd floor bathroom. The 4" main waste/vent stack passes through the first floor within 18" of the proposed new toilet. This existing drain line serves as a waste/vent pipe for a bathtub, sink & toilet directly upstairs. My question is this: What do I need to do to vent the new toilet? Do I need to construct some time of auxiliary vent for the new toilet, or can I use the existing vertical waste/vent stack as a wet vent? The sink in the new bathroom will have a separate vent, but because of the HVAC ducts/framing/etc... in the basement, it would be VERY difficult to provide an auxiliary vent for the toilet. If I need a vent, could it be run parallel to the existing stack? How would it tie in? Thanks for your help...
new toilet under existing bathroom...
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Jadnashua
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As to whether you need one, I'll leave this to someone else. Assuming you do, yes, you could run it up parallel with the existing drain. You can attach into it above the flood plane of the fixtures above it - they appear to often use 42" or so from the floor. It might be easier to do in the attic.
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hj
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Once the upper toilet was connected to the vertical pipe it stopped being a vent and became a waste pipe, so it would not be a vent for your lower toilet. You need a separate vent for it that either goes out the roof, or ties into a vent somewhere upstairs at least 42" above the floor.
Once the upper toilet was connected to the vertical pipe it stopped being a vent and became a waste pipe, so it would not be a vent for your lower toilet. You need a separate vent for it that either goes out the roof, or ties into a vent somewhere upstairs at least 42" above the floor.
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hj
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It all depends on the exact piping arrangement for your house. That is a generic diagram that could be adapted to many different houses by changing the dimensions of the piping. Knowing what to eliminate and how to do it is why there are plumbers.
It all depends on the exact piping arrangement for your house. That is a generic diagram that could be adapted to many different houses by changing the dimensions of the piping. Knowing what to eliminate and how to do it is why there are plumbers.
Homeowners like their shortcuts,
And then after they do it wrong, they love complaining to anyone that will listen.
The drawing is a standard way of plumbing in the United States.
In third world countries, where people are very poor, maybe it wouldn't look like that. Africa is one place I can think of.
Are you "third world" where you live?
Do you want to plumb your home so it works? If so, plumbers can do that for you.
The job should be permitted and inspected.
I'm going on a call tomorrow for a real estate transaction to inspect plumbing for a sale to determine how much the seller will be kicking back to the buyer to redo the "new" plumbing.
Any plumber will tell you it takes hardly any more time and money to do it right so it works.
But if that's too much work for you, just dig a hole in the ground and build an outhouse over it.
http://www.jldr.com/ohindex_realohs.shtml
And then after they do it wrong, they love complaining to anyone that will listen.
The drawing is a standard way of plumbing in the United States.
In third world countries, where people are very poor, maybe it wouldn't look like that. Africa is one place I can think of.
Are you "third world" where you live?
Do you want to plumb your home so it works? If so, plumbers can do that for you.
The job should be permitted and inspected.
I'm going on a call tomorrow for a real estate transaction to inspect plumbing for a sale to determine how much the seller will be kicking back to the buyer to redo the "new" plumbing.
Any plumber will tell you it takes hardly any more time and money to do it right so it works.
But if that's too much work for you, just dig a hole in the ground and build an outhouse over it.
http://www.jldr.com/ohindex_realohs.shtml
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Chill dude. I'm in the boonies, but not a 3rd world boonie.... I've actually had an inspector make me take out a vent because he said it was "not necessary".. I ended up being gun shy about vents and somewhat confused from time to time. Then I go to another job and there are vents everywhere which all tie in together to a vent which is teed in below everything else...big time overkill... then this plumber ran two 4" pipes out the roof and this high dollar vacation home has some hellacious roof leaks from a plumber with a really fancy layout. I just try to keep it simple as possible and be sure everything can flow without creating a vaccum to suck the countents out of something else....or causing the contents of something else to bubble....
Geniescience
Homeowner
sounds good to me.
i'll be coming back here to see how you handle your project.
Note that "The 4" main waste/vent stack passes through the first floor within 18" of the proposed new toilet. This existing drain line serves as a waste/vent pipe for..." is a misuse of the term vent. Once it becomes a drain, it's a drain. It may provide some wet venting , which is another concept, close but not the same.
However, back to square One: you say you already have plans for a vent, for the sink (good !!) and that this vent will be easy to build (good !) .
Now, the big question in your first post is whether the toilet needs a vent. The answer will depend on the distance and the layout -- how far your toilet is going to be from the vented sink, and how many bends too.
Draw this out. I use "MS Paint" to make a monochrome bitmap. The files are about 20k in size.
After you post your drawing, you will see how Terry an HJ are right, and we will see how you are right, too.
Travis, you are making good progress. But words alone won't help explain how Terry's drawing will cover your situation.
Summary: The venting that your toilet will have will come from some vent somewhere near the toilet, and most likely from the vent that is above your sink's P trap, assuming that your sink is within a few feet of the toilet. BUT it alll depends, and you posting a diagram or a drawing will focus the conversation on your real-life situation. How many feet, how much distance, this is important to include.
David
i'll be coming back here to see how you handle your project.
Note that "The 4" main waste/vent stack passes through the first floor within 18" of the proposed new toilet. This existing drain line serves as a waste/vent pipe for..." is a misuse of the term vent. Once it becomes a drain, it's a drain. It may provide some wet venting , which is another concept, close but not the same.
However, back to square One: you say you already have plans for a vent, for the sink (good !!) and that this vent will be easy to build (good !) .
Now, the big question in your first post is whether the toilet needs a vent. The answer will depend on the distance and the layout -- how far your toilet is going to be from the vented sink, and how many bends too.
Draw this out. I use "MS Paint" to make a monochrome bitmap. The files are about 20k in size.
After you post your drawing, you will see how Terry an HJ are right, and we will see how you are right, too.
Travis, you are making good progress. But words alone won't help explain how Terry's drawing will cover your situation.
Summary: The venting that your toilet will have will come from some vent somewhere near the toilet, and most likely from the vent that is above your sink's P trap, assuming that your sink is within a few feet of the toilet. BUT it alll depends, and you posting a diagram or a drawing will focus the conversation on your real-life situation. How many feet, how much distance, this is important to include.
David
Hey guys... that's why this forum has become a bad habit for me... I'm still learning lots everyday. Looks like I need to go to "vent school" to see how others do it. I've yet to have a problem with my designs or installs. It's just good to know different ways to do things. If it were me I'd probably opt to leave out the toilet vents since they are vented on either side by the sink and the tub. You have 1 1/2" lines feeding into a 3" drain/sewer line. The sink nor the tub will affect the toilet's proper operation.... if I'm wrong would someone please explain it to me?
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