Shower Drain and Vent
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It needs a separate vent as indicated in the picture on the right.
evogroup
New Member
thanks
2 folds., You need to vent the trap arm., The picture to the right., coming off the trap arm CAN NOT be a sanitary tee. that leads to the vent. You can not lay a sanitary tee horizontally to lead to a vent., it must be a Wye or a Combo.
Also., leave the waste branch arm of the shower as a combo to the waste stack which is what's in the picture., not a sanitary tee (just a better fitting)
I'm not sure about Boston, but both the IPC and the UPC allow Sanitary tees on their backs for dry vent connections as is the case here.
No the upc does not allow a sanitary tee on its back on the trap arm to lead to a vent.
It can be used on the vent section in any orientation. But on the waste section only in vertical.
I am more familiar with the IPC, and the questionable "internet search" said both codes allow it. And in some comments on other forums, it is put that certain codes do not "prohibit" it; aka it is allowed, depending on local regulations and the inspector's interpretations of the code.
So just to educate myself a little more on the UPC, can you give me the specific section of the UPC that prohibits sanitary tees on their back for a dry vent connection to a horizontal drain line? Thanks.
The only position I can install a sanitary tee below the flood level of any fixture is in the vertical position.
It’s good plumbing, codes he damned.
It’s good plumbing, codes he damned.
UPC
Section 706. Changes in direction of Flow
706.4 vertical to horizontal
The vent for the trap arm sanitary tee on its back would have the vent going from vertical entering the horizontal.
A sanitary tee is not approved
Section 706. Changes in direction of Flow
706.4 vertical to horizontal
The vent for the trap arm sanitary tee on its back would have the vent going from vertical entering the horizontal.
A sanitary tee is not approved
706.2 horizontal to vertical
Sanitary tees are approved in this section
a trap arm horizontal into the sanitary tee to thats on a vertical stack is an example
Sanitary tees are approved in this section
a trap arm horizontal into the sanitary tee to thats on a vertical stack is an example
"706.4 Vertical to Horizontal. Vertical drainage lines connecting with horizontal drainage lines shall enter through 45-degree (0.79 rad) wye branches, combination wye and one-eighth bend branches, or other approved fittings of equivalent sweep."
But 706.4 is describing "vertical drainage lines connecting with horizontal drainage lines." And for drainage line connections, a wye or a combo is definitely required. But a vent is NOT a drainage line, so that requirement is not applicable. As long as the Sanitary tee branch is vertical or no more than 45 degrees off vertical, per UPC, a sanitary tee on its back would be acceptable.
But yes, an inspector could interpret that the vent connection is a drainage line and apply that requirement wrongly.
Actually its a fitting on the drainage section of the plumbing., which is the issue.
I can go more specific, but the simple term is that fitting is attached to the sanitary drain section of the plumbing and not the vent section.
Yes, but.... Section 706.0 is for "Changes in Direction of Drainage Flow". As there is no change in direction of drainage flow for the attachment of a vent to a trap arm, section 706 is not applicable here.
Again, unless the inspector wrongly interprets that there is a change in direction of the drainage as it flows through the Sanitary tee on its back.
Again, unless the inspector wrongly interprets that there is a change in direction of the drainage as it flows through the Sanitary tee on its back.
Now on this
706.1 says Approved Fittings. Changes in direction of drainage piping shall be made by the appropiate use of Approved fittings and explain the angles....
And then the subsequent sub chapters explain each change in direction APPROVED FITTINGS allowed based on which change in direction of the piping.
That is the language why the Sanitary Tee is not allowed on a trap arm on its back., its attached to the DRAINAGE PIPING
Now on this., 706.0 Says Changes in Direction of Flow
706.1 says Approved Fittings. Changes in direction of drainage piping shall be made by the appropiate use of Approved fittings and explain the angles....
And then the subsequent sub chapters explain each change in direction APPROVED FITTINGS allowed based on which change in direction of the piping.
That is the language why the Sanitary Tee is not allowed on a trap arm on its back., its attached to the DRAINAGE PIPING
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so its not just saying flow of what is touched of waste fluids., But buy the fitting direction that is attached on the drainage piping., It doesn't become a dry VENT until it is above the fitting. Just like a horizontal wet vent is not a dry vent until above the sanitary tee of the sink if the Lav sink is the wet vent upstream. Above the Sanitary Tee fitting would be the vent section.
I agree! The sub chapters explain each CHANGE IN DIRECTION approved fittings allowed based on which CHANGE IN DIRECTION of the piping. So that is pretty clear that a CHANGE IN DIRECTION being performed by a particular fitting is required for this chapter to be applicable.
If that is not the case, then it DOES mean that any fitting touching a drainage line needs to conform to the "Changes in Direction of Drainage Flow" section.
Every code requirement is there for a reason. As there is no flow through the branch of a Sanitary tee or a combo being used as a vent connection to a horizontal line, there doesn't seem to be a reason for the way you are interpreting the Change in Direction of Drainage Flow section on the UPC. I guess there could be a benefit should one need to snake the vent line, but there would need to be a cleanout available to do that.
And then again, some inspectors don't have a logical mind, nor can they be reasoned with.
Well., ad you've said interpretation.,
The fitting itself receives waste when its on its back., thru the top and bottom. That alone means the fitting is not being used in its correct way.,
Multiple aspects on why its not allowed by language.
Maybe an update they can make the code clearer on fittings used to tie in for the vent from the waste. Another subsection.
But as it stands, that fitting would be touching waste on its backside making it apart of the drainage system.
???????
Do you have to argue your point to exhaustion everytime? Listen I've had a little screw up with miced69 and I stopped. It was my fault and my fault for trying to fix it by going on. He has a world of knowledge. Regardless right or wrong just stop. It's like you have to have the last word or be more right then the next. 5 plumbers, 5 different ways and none of them are wrong. You can plumb a lot more ways then just your way and it would pass. I've had wyes with street 45s vertical and the inspector passed it with no problem. Yet by code it should've been a sanitary tee. Everyone here brings a bit of knowledge to the table. Some more then others. But this is ridiculous to argue over making your point. I've put sanitary tees on its back in nj and passed as well. Philly is required for cast packed and poured still, jersey its not. I use pipe dope you don't. So what?
Was saying each body words it so the inspector can rule either way to pass or fail you.
Hopefully they just make a clear subsection on the use of fittings for a trap arm to lead to a vent.
Some counties actually did just that because it leads to inspectors going either way...
In the grand scheme of plumbing, the fitting doesn't hurt in that regards lol
