my wife wants to reorder the fixtures in our small bungalow bath, she wants the order to be lav, water closet, tub then the soil stack. my question is can they all be on one 4" horizontal branch drain as long as I don't wet vent the tub?

No. They all can be on the horizontal branch if you wet vent the tub with the lavatory.

will this work? this is a first floor bathroom on a full basement.

Its close, I can't tell exactly how you have your vent for the tub. If theres a tee in the vertical vent for the tub then its all good.

I would have to know what kind of fitting you are using to vent the tub.

if you tie the tub drain in over to the left side of the toilet, it will be a perfect wet vent. tub and toilet will vent up thru the lav. no separate tub vent needed..

the soil stack is cast iron. what is the best waay to tie in?

this is what I am trying to replace, I plan on entering the stack where the the closet bend is. What is the best way to deal with the cast iron wye underneath that? put a clean out there?

We do not know your level of experience and how WE would do it is probably NOT how you can. As far as your new drain setup, as soon as you went OVER the 4" with the tub drain you created an illegal "S" trap.

how would you tie the tub in before the water closet like packy suggested.Or would it be better to not wet vent the tub. would the first drawing be right if like suggested if tub first goes into sanitary tee with the vent running up and dropping into a long sweep wye below?



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yes to the last question.

Thank you sir.



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