I called this up as an S-trap the other day but the plumber called in to fix it is saying I am wrong. Before I get into an argument I thought I would put up a picture to see what the guru’s from the message baord had to say. Yes I did notice the drain for the dishwasher.:mrgreen:
Greg, in my posted diagram, (Ex 2) the measurement (2x trap dia) is the key.
IMO… the reason the plumber is not calling this an S-trap is due to him using (Ex 3) for that measurement, when in actuality, it is still (Ex 1). The 45 degree angle down-slope is NOT to be misconstrued as horizontal, and MUST be considered as verticle.
SO… if the measurement (EX 2) is 2x the trap diameter or larger, it is NOT an S-Trap. If it is smaller than 2x the trap diameter, it IS an S-Trap.
I wouldn’t consider it to be an “S” trap just because the trap arm is connected into a wye rather than a sanitary tee.
The difference between it and the two “S” traps in the laundry stand pipe demo pictures is this one has a continuous vent.
The dishwasher discharge however needs to be trapped to prevent sewer gas from entering the dishwasher unless the dishwasher has a positive closing drain valve.
I forgot to come back on with an update. Sorry guys. Ok first and foremost the seller admited that a local handyman with no credentials dig the work and so wheen they called him back to fix it he was ticked off and would not agree with me. A plumber from town got called in and fixed it. I talked to him a couple of days later and he confirmed it as an S-trap. He also talked about the 42" rule for the turn. The dishwasher drain was also wrong which we knew about. I win I win I win. Just not what it was i won!!!