Hi all,

I live in Pa and I am installing a sink, toilet, and shower in my basement. The house was built in the 60's and the bathroom plumbing was roughed in using clay pipe. I am replacing the clay pipe on this branch with PVC. The bathroom will be 18 ft from the stack on the other side of the basement to the right of my backdoor in a room I have framed in. Do I need to create a separate vent system for this new section? Would a cheater vent suffice since I am so far from the stack? It would be beyond my ability to run a vent to the roof. How is this usually done? I have included very rough diagrams below. Please be kind.

Thanks, Mike

It would be best to get a plumber on site to assess the situation and determine the best course of action.

trying to be kind...
your first drawing is not up to code as there is a full S trap drawn.
the second gives some sort of below grade layout but not enough information to advise on.

if cheater vents are legal in your area, you could get away using 2 of them. one behind the vanity and one inside the shower wall venting both shower and toilet.
back to your drawing board...

You need to do more research about venting and pipe layouts. I really can't imagine a house built in 1960 having clay pipes under the concrete floor. That would be more likely with an 1860s house, or even one in the 40s, but not any later since the war was over and metal pipe was readily available.