I am thinking about installing a basement wet bar w/ sink. There is a main sewer line coming from upstairs, going straight into the cement (has a cleanout about 2.5 ft above floor). The location I am looking to install the sink will be roughly 36 ft from this main swere line, with two 90 degree turns. I am assuming 1/4" drop per ft. of drain line off the sink to the sewer main. My question is concerning the tie-in to the sewer main. How simple / or not so simple is this? Would I run the pipe from the sink to the sewer main using the 1/4"/ft. drop in my run, and then go into the sewer main at a 45 degree angle? I am concerned about not backing up my basement sink off the sewer main.

I notice you haven't mentioned a vent off the bar sink, (every fixture having a trap MUST be vented). Figure 18" off the floor to pick up the bar sink and a 9" drop at 1/4" to the foot which will leave you a 9" drop to the floor line. How did you plan on connecting to the sewer? If you have a floor drain in the basement then a back up will come out the floor drain and not your wet bar. Good luck, Tom

What is usually done to tie in to the sewer main?

What is usually done to tie in to the sewer main?

Cut in and roll a combination wye and eighth bend up on a 45 degree angle from the main and 45 down to it from the drain line. Good luck, Tom