Basement Bathroom waste and vent pipes

[daverau123]

Hi Everyone,

Looking for some advice on plumbing my basement bathroom. I'm tearing out some mistakes the last owners put in (including a shower with no trap 2 feet from a toilet), and want to make sure I'm proceeding properly. I have a basement bathroom directly below my main level bathroom. All fixtures are within 5 feet of the stack. Nothing is vented at the moment (not sure if it needs to be as it's within 5 feet of stack). However, I do have a 1 1/2" vent that comes down to the basement and runs up to the stack above the highest fixture in the house that I can tie into if need be. I have attached a picture (sorry it's so crude) that details both floors of my house. Is the current setup acceptable? If not, can I tie into the existing vent to sort things out, or do I need to go another route? I should note that the stack is 3", the pipe running at the bottom (under the slab) is also 3". I have the option of running any size I want to the shower and sink in the basement as the floor is dug up at the moment (thinking of running 1 1/2" or 2", not sure if that will make a difference). Any help you can offer is much appreciated.

Thanks,

Dave

 

[Matt30]

I would individually vent that basement tub with the extra vent then wet vent the toilet off of that.

 

[daverau123]

I would individually vent that basement tub with the extra vent then wet vent the toilet off of that.

Thanks Matt30, totally agree -- had a closer look and the existing 1 1/2" vent is actually venting some other fixtures already, so went and picked up some ABS pipe and fittings last night to run a new vent off the tub. Running a 2" waste from the tub and a 2" vent off of that - will also tie in a downstairs bathroom sink and kitchen sink to that same vent. Just have to cut a hole in my upstairs bathroom wall to access the stack, easy enough to patch up after.

Might as well do it right rather than overloading an old undersized vent.

Thanks again for your feedback!

 

[frodo]

LOL, your drawing is like mine...

look at this drawing of mine, you have some code issues that need to be addressed

you need to add a waste stack for the lav/sink
it cant drain into the upstairs piping
it needs ti be 2" shower needs to be 2"
the problem you are going to have is your vent
a toilet vent size is 2" and you have a 1 1/2 in the ceiling