My house was built in the 50's so I've got a cast-iron stack that drops out to the road about 4' up my wall. I'm putting in a basement bathroom and need to vent the system properly. I've been on this forum to figure out how to vent my drainage but now I need to vent my ejector properly.

I can't get a 2" pipe up through the wall where my stack goes up to the roof. There is also a drain up higher in the 2nd storey that drains into the stack so I can't tie into the stack at all. I have a 1.5" pipe going out the roof that isn't being used on the other side of my house. I should be able to replace the 1.5" pipe with a 2" pipe and get in the attic to connect it into the roof vent (which is 3").

Here is the problem: The roof vent that I want to run would require an approx. 35ft. Horizontal run (on a slight grade for water in line). It would then run up to the attic (just one storey), then over another 3ft. Horizontal run then into the roof vent.

Is this a problem or will this vent work even with a run like that?

I've included a drawing.

As always, any help is much appreciated!

Where did you tie in your ejector drain? That stack could be your wet vent.

Jonstar... should be no problem on the run of vent as presented. Pitch it as mentioned and will be fine.