How do you install a running trap for a bathtub?

Answer 1

most places don't allow a running trap and instead allow a P trap with a vent. If you don't care about codes and want to install (not a good idea) a running trap then simply buy a P trap with another street 90 and hook up your drain line to both sides of the trap horizontally. If you want to install your tub trap the right way then use a P trap with a vent line down stream of your trap.

A running ( P ) trap can be ( 4 ) 45 degrees fittings in DWV, or ( 4 ) 1/8 bends

in cast iron fittings. I would use a long sweep in either fitting from your tail

peice off your trip waste ( whitch is your drain hardware from tub ) running

horizontally install all ( 4 ) either fittings in horizonal drain line. Make sure you

put the first fitting looking down,next one looking straight,next one looking up,

next one looking straight, this will be putting you back in line with horizonal line

again. I would make sure you have either a vented line or auto vent somewhere in line. If you use off of a vented line make sure you are no more than 6 feet away from this line in ( 2 in. ) pipe. Like if you were taking off a

drain line going to a lav. or other fixture, the vent to that fixture starts right

above drain line sticking out wall if it is a lav. You start off with drain line

sticking out of the wall if it is a lav. and buy the time you get to where you are connected to your tub drain will be no more than 6 feet away A auto vent can be installed anywhere you can on the drain line, it can even be lower than the tub, but higher than your drain line. If you do not fully understand how to do

this, i would call a plumber. The only reason you would want to use a

running ( P ) trap, is if you did not have the room to install a ( P ) trap. And

alot of times you do not have the room for a running ( P ) either.