Side-inlet Quarter Bend Allowed for toilet?

[jblacksten]

I am in the process of replumbing my hallway bathroom and in the process I need to run all new drainage lines. The old plumbing was cast Iron and galvanized. They ended up cutting a floor joist in order to get the fittings to fit. I have since fixed that but have limited space from where the stack comes up to the second floor and where the toilet is. I wanted to know if it was possible to use a side-inlet quarter bend that would go straight up to my toilet and feed my tub/shower and sink drain?

Where the stack comes up to the second floor, it has a 3" vent going all the way to the roof. Plus I have an 1" -1/2" vent over by the sink. I do not know a lot about plumbing but I assume that the 1-1/2" vent is a wet vent that would lead into the side-inlet quarter bend.

 

[jblacksten]

I am in the process of replumbing my hallway bathroom and in the process I need to run all new drainage lines. The old plumbing was cast Iron and galvanized. They ended up cutting a floor joist in order to get the fittings to fit. I have since fixed that but have limited space from where the stack comes up to the second floor and where the toilet is. I wanted to know if it was possible to use a side-inlet quarter bend that would go straight up to my toilet and feed my tub/shower and sink drain?

Where the stack comes up to the second floor, it has a 3" vent going all the way to the roof. Plus I have an 1" -1/2" vent over by the sink. I do not know a lot about plumbing but I assume that the 1-1/2" vent is a wet vent that would lead into the side-inlet quarter bend.

I have attached a crude drawing of what I am trying to do.

 

[Sponsor]

 

[James Henry]

That won't work. A more detailed drawing would help too.

 

[jblacksten]

That won't work. A more detailed drawing would help too.

I am not great at drawing nor do I have software to help but I tried to show it a different way. I forgot to draw in the 1-1/2" vent pipe at the sink but it has one. Why would it not work? I thought I read in the 2021 International Plumbing Code (IPC) that you could use a side inlet quarter turn, but not sure if it will cause flow issues.

 

[John Gayewski]

A vent that is horizontal under the floor needs a fixture attached to it to wash out solids. I hope the helps you figure out what you can use. Your drawing is still confusing to me. Usually a side inlet 90 can only be used in one orientation and it doesn't look to me like your have it correctly.

 

[Robert Gift]

Can the side inlet not be at the side but be raised so the anyvater in the vent will continue flowing dowhill and into the three-inch pipe?
Could it be at the top _/_ of the three-inch pipe? Or no room?
Would be nice to have a sink washing any solids through the 1-1/2 into 3" sanitary tee. (I am not a plumber and do not know any codes.)

 

[wwhitney]

The side inlet on a side inlet quarter bend can only be used for dry venting, it may not receive drainage. In the drawing in post #4, the proper way to combine the tub/sink drain with the WC and wet vent the WC is to use a horizontal 3x3x2 wye downstream of the closet bend.

Or, if the 3" stack is in fact a dry vent above where the WC hits the stack, bring the tub/sink drain to a 3x3x2 san-tee on the stack above (vertical wet venting) or below the WC drain, or use a 3x3x3x2 san-tee with side-inlet to bring them both into the stack at the same elevation.

Cheers, Wayne