Combination tee to put wet vent upstream of toilet

[DMC86]

I have searched over the internet and not been able to find any images close to how I would like to install the plumbing in a bathroom addition, which makes me worried that I am missing something. Could anyone knowledgeable in plumbing please advise if their are any code issues (or issues otherwise) with the using a combination fitting attached below a toilet flange, and using the back/upstream side of the fitting to plumb a wet vent shared with a tub? Hard to explain in words, but I drew a rough sketch to help show what I mean.

The reason for doing this is I do not want to box or adjust floor joists in the wall downstream from the toilet to allow for a vent pipe to fit, also using the wall upstream of the toilet gets me close to my main 3"vent which I may tie into.

Thank you

 

[Jeff H Young]

looks good . I'd run the 3 inch up to the 3x3x1 1/2 santee for tub then bush down 2 inch for the rest of way up to a 2x2x1 1/2 santee

 

[Sponsor]

 

[Reach4]

Could anyone knowledgeable in plumbing please advise if their are any code issues (or issues otherwise) with the using a combination fitting attached below a toilet flange, and using the back/upstream side of the fitting to plumb a wet vent shared with a tub?

Stand by. There may be contrary opinions on having the toilet come in from above rather than from the side under IPC.

I think it would work well.

 

[Jeff H Young]

Stand by. There may be contrary opinions on having the toilet come in from above rather than from the side under IPC.

I think it would work well.

Oh really didnt know it could matter? Ill be standing by as well, thanks reach4!

 

[DMC86]

Thank you for the replies.

Jeff H Young, I am not sure I am understanding your recommendation, would it also involve adding an additional wye and 45? And would the result be two vertical vent stacks to be tied in above the tub water line?

Reach4, That is what I was afraid of as having it come in horizontally will mean rethinking and definitely additional work, I will standby.

 

[Jeff H Young]

I think reach 4 makes valid point . toilet may need to enter the horizontal from the side rather than through the top. I dont horizontal vent much . dont know the layout but theres other ways to do it . is it all dry walled and this is in basement ? underground?

 

[Reach4]

Found https://terrylove.com/forums/index.php?threads/toilet-venting-question.87477/#post-627554

Logically, I see no problem with the original proposal.

 

[Jeff H Young]

Found https://terrylove.com/forums/index.php?threads/toilet-venting-question.87477/#post-627554

Logically, I see no problem with the original proposal.

I dont either but looked at some info on web and it said that the w/c needs to enter the horeizontal line at same elevation as the vent. but I wasent sure of the authority and whether that was ipc code. I would be confident of its function but dont want to say its legal now there is some question.

 

[DMC86]

Thanks again. This is not a basement and it is not dry walled. In following the provided link, and then googling based on the answers (and terms used), it seems common thought that having the vent how I proposed would reduce suction when the toilet is flushed. I have not found a clear answer on whether it is against code or not, but I think I will just do the extra work to put the vent downstream of the toilet to safe. Thank you for your help.

 

[Jeff H Young]

dmc86 good luck