Is my plan ok to replace kitchen sink drain line?

[Tireshark]

When they built the house, they dropped the drain right in the middle of a floor joist. They cut out a notch in the joist, but didn't leave enough room, and the copper has developed a leak presumably from decades of rubbing against the wood.

It's on the end of the drain line, so I figure the easiest thing to do is just cut off the end of the main drain line, and run PVC all the way up to the sink. It looks like they used a sanitary tee, but from what I've read, it seems that a wye should be used for a vertical to horizontal transition. Does the diagram I have here look acceptable?

I will ensure that the PVC is not in contact with the joist, by widening the existing notch a bit. We are in a rural area, and code/inspections aren't really (much of) a thing here... mostly looking for input to save multiple trips to the hardware store, hah. Thanks for any input!

 

[Terry]

Yes on the wye to replace the santee in the crawl space. I would move the drain to miss the floor joist.
Instead of S trapping the sink, it should have a p-trap vented with an AAV. The S trap can siphon dry allowing sewer gas into the kitchen. Not what you want to smell while cooking dinner.

 

[Sponsor]

 

[Tireshark]

Great info, thanks Terry!

 

[Jeff H Young]

Looks like a good plan. Adding the AAV is by far the best thing to do as well. Santee on back wasn't good. No idea why original plumbing the guy notched into the joists not a big deal but extra work to accomplish nothing. You might need to oblong holes for PVC as its bigger around than copper

 

[John Gayewski]

The drain should be 2". If your doing this work you might as well make it the correct size.

 

[Jeff H Young]

First off I would never run 1 1/2 to a kitchen like they do in places that use IPC Code I run 2 inch minimum to every sink and rarely do I run 1 1/2 to even a lav.
But 1 1/2 is correct minimum pipe size in IPC If I was looking to repipe I'd go 2 inch