[RogerK]

Let me start by saying I am remodeling a small slab house in Englewood, FL. This cinder block house was built in 1950 and has a cast iron main sewer pipe under the toilet.

I might add that I am not living in this house during the remodel. I am both new to remodeling and also new to this forum but I am a quick learner and I am comfortable with tools. I have read at least 10 pages of this forum to find similar questions before this question.

Little more background... The bathroom is too small and moving cinder block walls is not an option. The front of the toilet was too close to the built in shower wall. I am pretty good with a computer so I bought some 3D houseplan software and modeled the whole house down to a +/- 1/2". This software allowed me to move things around and try different layouts within the bathroom footprint. My solution was to use a corner toilet and a neo angle shower. This layout gives me plenty of room for both the toilet and a 38 x 38 neo angle shower.

Little more background... I removed the old toilet. Threw it away. BTW I removed the walls of the built-in shower. Dirty job :( I will be installing furring strips and drywall on all interior cinderblock walls. Total thickness = 3/4" + 1/2"=1-1/4". The toilet main with metal flange is in the corner of the bathroom, 14" from one exterior cinderblock wall and 12" from the other exterior cinderblock wall. The corner toilet requires a 12" rough-in from each wall. This means the 14" will work considering the wall build out but the 12" will not work.

And now down to my question. Should I try to replace the existing flange with a 2" offset flange or should I use a cement saw and take out the entire cast iron main pipe all the way to the city line (only 5 feet = 14 inches in cement floor + under 8 inch exterior cinderblock wall and then 3 feet to the city sewer main line) and replace it with a new PVC sewer pipe in the location that I need it to be.

I have never done anything like this before but then again because of budgetary reasons, I find that I am doing many things in this remodel that I have never done before.

Reason for my question... Can I use a PVC offset flange on a cast iron main. If so, that would be great but I don't know if that is possible. I am considering the following offset flanges.

Find Offset Closet Flange, PVC 3" x 4" and other Toilet Repair at Aubuchon Hardware

Find Offset Closet Flange, 4" x 3" and other Toilet Repair at Aubuchon Hardware

Find Closet Flange Offset and other Toilet Repair at Aubuchon Hardware

Your expert advice would be really appreciated. Thank you.

Attached is a layout of the bathroom.

[speedball1]

Should I try to replace the existing flange with a 2" offset flange or should I use a cement saw and take out the entire cast iron main pipe all the way to the city line (only 5 feet = 14 inches in cement floor + under 8 inch exterior cinderblock wall and then 3 feet to the city sewer main line) and replace it with a new PVC sewer pipe in the location that I need it to be.

IMO a 2" offset flange's just asking for trouble. Having said that it would be your easiest out. If it were my job I'd convert to PVC. Good luck, Tomn