The way the 2" rough in went we ended up with a trap of sorts then a pipe to where the tub trap will be. Not completed yet.
Just wondering if a tub trap and a trap made with the rough in piping will cause some sort of problem. the rough in trap was made off of a 4x4x2 wye. Would that be adequate as a trap by itself if there should only be one?
Thanks,
Rosharo

ballengerb1

Here is the rule, one drain, one trap. Please explain or post a picture reagrding what you mean when you say "a trap of sorts." usually they are or are not a trap.

rosharo

The fittings formed a trap. Will look at it again today but it's like if you used a 90 st down a second 90 st into that and a 45 st coming up vs a another 90 st if you were making a normal 'trap'.
Anyone know why 'one drain, one trap'? Is it because you don't need another one or is is because there is a potential problem is you do use 2.
Thanks.

speedball1

Anything in a drain line that bells down and holds water's a trap in the line. Double traps are illegal for the same reason as "S" traps. Because the traps aren't vented it's possible for the draining water to suction the water out of the trap allowing sewer gas to enter your home. Does this answer your question? Regards, Tom

rosharo

Yes, Tom....answers it very well! The light dawns. Thanks.