I am adding a bathroom in my basement. After much research I decided to go the sewage ejector pump/pit route. I have a 90 year old bungalow with a 4" cast iron soil stack and 2" galvanized vent. The main floor bath is directly above the new bathroom location. When we bought the house, there was a toilet only in the basement. After breaking the concrete around the stack and digging around I found the 4" cast iron transitioning to 6" clay (via a 4" sanitary tee w/ a 2" side inlet) and then out to the city sewer. I didn't like possibly damaging the clay so I went with the pump/pit option. I have the DWV system designed & dry fitted which brings me to my questions (I will post pics when I get a chance) :
1) I have cut off the original closet flange to make room for the new toilet location. Is a fernco cap suitable for under slab application?
2) I was thinking of cutting a no-hub 4" c.i. wye and then tying the sewage discharge into that. Since I have to cut into the 2" galvanized vent to tie in my new vents anyway, can I use the remaining stub coming up from the original sanitary tee w/ side inlet as my tie in from the pump?
3) I read that the pump/pit should be vented separate from the rest of the venting, however this isn't really feasible. Why is it not ok to tie into the same vent? Can I vent out the side of the house?