Do You Need A Vent For A Shower Drain. If the plumbing air vent or vent stack becomes completely blocked a vacuum will form and you will no longer hear gurgling. Easiest Way to Vent Bathroom Plumbing.
This is because the P-trap under a shower isnt accessible. The fixture without a vent may drain slowly. You can run them level so long as there are no obstacles to work around.
If there is already a vent because you have a sink and toilet you could possibly tie into that for drain and vent.
If you cant clear a slow-flowing drain with a plunger auger or drain cleaner the vent blockage may be severe. The sink drain pipe and the tubshower drain pipe are vented with 15 pipe that branches off from the 2 PVC mainline. So the additional slope of just 18 inch per foot reduces the allowable drain length between the trap and vent. If you pull the tub and replace it with a shower you will be required to make the entire run of the drain line with 2 until it connects to a larger line.
