I'm putting a basement toilet in for my son in an older home. It had a 3" laundry standpipe available. We moved the washer and dryer to make room. the standpipe is only 9" from the wall and I want to bring the laundry drain and sink drain into it below the floor level, so I figured it was just easier (not easy) to remove some of the floor and do it below grade. Upon cutting the floor out and doing some digging 2 things showed up:
1) the pipes ran no where near where I thought they'd be (didn't really surprise me, which is why I broke the floor bigger than I needed
2) There appears to be an S trap between the standpipe and the stack. Unfortunately we stopped breaking floor beside the HW heater and furnace, and the S trap will need to be tunneled out from under the floor. Not a fun job, but hey, it's his house not mine.

My question - is it imperative that I remove the s trap? I realize it becomes a great place to plug the drain under the cement floor, but maybe I'm worried about nothing. I'd appreciate any comments.

Cheers,
Ed

There appears to be an S trap between the standpipe and the stack. Are you quite sure that it's not a "P" trap? A "S" trap would point down while a "P" trap would connect to the stack.

My question - is it imperative that I remove the s trap? I would remove the trap and cap off the line. Don you need assistance in laying out the rough in? Back to you, Tom