I am working on remodeling my basement and have many issues to contend with. The first is the trap for my tub drain on the first floor is well below the floor joists and I would like to raise it up to be able to have a relatively normal ceiling height in the basement. I have been reading that the distance of the 2" drain after the trap to the vent has to be five feet or less. My question is can a trap be anywhere in the drain line or does it have to be a certain distance from the tub and then the vent has to be 5' feet froim the trap. Can someone please clarify.

Thanks in advance

Hey Jeff,
You asked, "My question is can a trap be anywhere in the drain line or does it have to be a certain distance from the tub and then the vent has to be 5' feet froim the trap?"

The trap and raiser is positioned directly under the tailpiece of the tub waste and overflow that it must connect to. Any place else and that "P" trap then becomes a "S" trap which is illegal in all of the US and Canada. With 2 X 6" floor joists you should have no problem in raising the trap and drain line above the ceiling height that you desire. Good luck on your project. Tom

Thanks for the quick response. As a follow up. Do I only have 5' of length to play with from trap to waste stack? What is the draw back if it is longer, and do the same rules apply if it is a stand up shower only?

Thanks for the quick response. As a follow up. Do I only have 5' of length to play with from trap to waste stack? What is the draw back if it is longer, and do the same rules apply if it is a stand up shower only?

You can "fudge" a bit on the distance, especially if you're not going to be inspected. But if you're connecting to the waste stack below where the toilet ties in then that is not acceptable. Code states that you may not discharge a major fixture, (toilet) past a unvented minor one, (your tub) If that's the case then you must "wet vent" the tub by connecting it to the lavatory drain.
The same rules apply to ALL fixtures that have traps.
Code states that the distance between trap and vent be;
1 1/4"--- 2 1/2'
1 1/2"--- 3 1/2'
2"------- 5'
3"------- 6'
4"------- 10'
Let me know the configuration you're using to vent the tub. Regards, Tom

I was thinking connecting the tub drain to the existing drain from my kitchen sink with a T.

I was thinking connecting the tub drain to the existing drain from my kitchen sink with a T.

Please explain with details. Tom