I have read some earlier posts and thought they were very informative, so I thought I would post my delema.

I have built a new addition part of which is a new master bath. Along the backwall there is (in row) Toilet, Tub and a separate shower. My original plans call for a 3" drain connecting all 3 fixtures and then tying into the main drain stack. My questing is regarding venting. Can I simply "WYE" one 2" vent at the end of the 3" run before the stack. The stack will be around 25' linear feet away. Option #2 is to put a 2" WYE on each fixture after the trap but before it ties into the 3" run. Creating a parallel 2" vent for all fixtures next to the 3" drain. Which method will meet 2000 Codes? NOTE: My joists all run parallel with the 3" drain line, so doing option #2 should be easy.

Thanks in advance

I have read some earlier posts and thought they were very informative, so I thought I would post my delema.

I have built a new addition part of which is a new master bath. Along the backwall there is (in row) Toilet, Tub and a seperate shower. My original plans call for a 3" drain connecting all 3 fixtures and then tying into the main drain stack. My questing is regarding venting. Can I simply "WYE" one 2" vent at the end of the 3" run before the stack. The stack will be around 25' linear feet away. Option #2 is to put a 2" WYE on each fixture after the trap but before it ties into the 3" run. Creating a parallel 2" vent for all fixtures next to the 3" drain. Which method will meet 2000 Codes? NOTE: My joists all run parallel with the 3" drain line, so doing option #2 should be easy.

Thanks in advance


Option #1, No,
Option #2 will work If you install the 2" wye within 5' of the trap but it's overkilll.
Let me give you Option #3.

Toilet at end of 3" main. Lavatory drain tied into the 3" main vented out the roof. Tub/shower to tie into the lavatory drain and be wet vented. Sound like a plan? Tom