: What is meant when I hear plumbers talk about the vent takeoff needing to be 6" above the flood rim of the fixture being vented? I must be missing something crucial in the concept because it doesn't seem like this is ever the case. Isn't the vent takeoff at the san-t, which is in the wall just above the trap? Thank you very much to anyone who can explain what I am not understanding.
Jeff. What they mean is the vent being vertical after the san tee, may have to turn and go horizontal. At that point the horizontial vent must be a mim 6" above above the flood level rim of the fixture it is venting. A kit sink is 36" off the floor so the horizontial vent must be at least 42" off the floor. Now you can measure the toilet (17") lav, (30") shower dam,(3") tub (14") and add 6" to each one. But to make life simple for all involved most plumbers just make all the horizontal vents 42" off the floor. Hope this helps. Dale's Plumbing Service LMP