Creative Plumbing?

I ran into some creative plumbing in a crawlspace the other day, well, at least it nothing I have ever seen before. Two ABS waste line come from a bathroom sink, one appears to be a vent line the other the drain. In between the drain line and the main waste line, is the p-trap (no trap below the sink). Is this even close to code?

2014-04-28 11.56.20.jpg

               Nooop…:shock:

trap diagram - Plumbing Inspections - InterNACHI®️ Forum

Interesting installation?

Looks like it would work though.

no supports either…

it does look like it would work. isnt that what we are after?

It would suck for the home owner to fix anything there if that is a crawl space you are in :slight_smile: Did that cup have signs of moisture as if that is leaking?

In order for it to not be an S trap, a P trap has to be below the level where drain line enters the larger drain. That does not look to be the case.
Slope should be no more or (or less) than 1/4" to the foot. Looks like more

Say whatever about it but I’ll bet a licensed plumber did that hookup.