Washing Machine - Move From 1 1/2" Vertical Line To 3" Vertical Main Stack?

[Bluegrass Picker]

We are wanting to move the washer and sink, so the washing machine drain needs to go to the opposite side of the main stack.

House was built in 1968.

Existing washing machine drain in basement is 1 1/2". Main waste stack is 3" and has 2 toilets, 1 tub, 1 shower connected from floor above, then it goes to the roof.

Would it be ok to cut the main stack as shown in the photo and install an ABS wye with a 2" P trap for the washer? We would be extending the horizontal line about 3 feet from the Y to the washing machine riser P tap. Would the venting provided by the 3" stack suffice?

Additionally we intend to cut the 1 1/2" existing sink drain and utilitze the side of the santee that goes to the existing washing machine drain to feed into the vanity on the other side of the wall.

Would it be ok to use the existing P trap along with another P trap inside the vanity or should I cut out the existing P trap and plumb the vanity using its own P trap on the sink?

Thanks in advance.

Bluegrass Picker

 

[Terry]

The washer will need it's own venting before it enters the 3" stack. Toilets being flushed from above with knock the water out of the trap seals unless they are vented.
That vent can then tie into the sink vent at 6" above flood level of the fixtures served.

 

[Sponsor]

 

[Bluegrass Picker]

Thanks very much! I'll run the vent over to the 1 1/2 vent stack.

Should I cut out the existing 1 1/2" P trap from the old washer standpipe and then plumb the vanity on the other side of the wall from there, or just leave the P trap and install a second one in the vanity?

Thanks again,

BluegrassPicker

The washer will need it's own venting before it enters the 3" stack. Toilets being flushed from above with knock the water out of the trap seals unless they are vented.
That vent can then tie into the sink vent at 6" above flood level of the fixtures served.

 

[Terry]

The lav only gets one p-trap, so cut out the old washer standpipe and have the p-trap for the lav under the bowl.

 

[Bluegrass Picker]

Thanks! I deeply appreciate your help.

That ka-ching sound you just heard was the tip jar.

Thanks again,
BluegrassPicker

The lav only gets one p-trap, so cut out the old washer standpipe and have the p-trap for the lav under the bowl.

 

[Terry]

Thanks! I deeply appreciate your help.

That ka-ching sound you just heard was the tip jar.

Thanks again,
BluegrassPicker

Thanks!