Hi there,

I live in an 800 square foot slab on grade home with 1 bathroom. I am adding a second story and including a bathroom and laundry room on the second floor. I positioned the bathroom by the main stack and the laundry further away. I intended for the toilet, sink, and tub and washing machine to drain into the main stack with the tub and sink also venting into the stack. The washing machine would have its own separate 2” vent.

The inspector did not like it. He told me nothing that goes on the second floor can drain into that stack. He said that the stack was meant for the bathroom on the main floor only. He says that I will need to break up the floor and tie the 2nd floor fixture drains in past where the toilet on the main floor connects. This doesn’t make sense to me and it seems there must be an simpler way. I look at diagrams in books and see similar stacked bathrooms. Isn’t this the point of stacking bathrooms – to be able to make use of that 3” stack to drain the upstairs?

I hope I’ve explained my predicament well enough for some help.

Thank you so much,

Quote:

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Originally Posted by dale healey

Hi there,

I live in an 800 square foot slab on grade home with 1 bathroom. I am adding a second story and including a bathroom and laundry room on the second floor. I positioned the bathroom by the main stack and the laundry further away. I intended for the toilet, sink, and tub and washing machine to drain into the main stack with the tub and sink also venting into the stack. The washing machine would have its own separate 2” vent.

The inspector did not like it. He told me nothing that goes on the second floor can drain into that stack. He said that the stack was meant for the bathroom on the main floor only. He says that I will need to break up the floor and tie the 2nd floor fixture drains in past where the toilet on the main floor connects. This doesn’t make sense to me and it seems there must be an simpler way. I look at diagrams in books and see similar stacked bathrooms. Isn’t this the point of stacking bathrooms – to be able to make use of that 3” stack to drain the upstairs?

I hope I’ve explained my predicament well enough for some help.

Thank you so much,

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The inspector was correct when he told you that you couldn't discharge one bathroom into another one. Did he mention running individual vents from the first floor bathroom up and reventing back into the vent stack at least 6" over the 2nd floor lavatory. That way you would have converted the first floor vent stack into the second floor stack vent and still use it. Another way would be to connect to the sewer outside the house and run a three inch pipe up the outside and use that for the new stack vent. The toilet could discharge in to the three inch stack as could the lavatory and laundry after they revented back into the three inch. The tub/shower would connect into the lavatory drain and be wet vented by it.
There! Now you have options. The only thing is they all involve major surgery. Good luck and enjoy your turkey. Tom