Shower Addition to Bathroom - Drain Tie-In Question (B.C.)

[sprusgoose]

Hey all. I'm undertaking my first major renos at my place and am looking to install a shower in an existing bathroom. I have attached a picture below of my intended layout. Blue is the existing lavatory connection to a 2" stack, red is the toilet connection to the 3" stack. The question is, can I tie the shower drain into either the 3" or 2" stacks without an additional vent (wet venting I believe)?

As best I can tell after polking a few holes here and there and going into the attic, the two stacks tie together and are vented through a single 2" vent. The run to the 2" stack (the further of the two), is about 6' from the intended shower drain. The 3" line has one more toilet from the upper floor tied to it, and the 2" line has a tub/sink from the upper floor, and a kitchen sink on the other side of the main floor bathroom (pictured).

I'm located in B.C., Canada...any help is appreciated. And let me know if I can provide any further info.

 

[Terry]

The trap arm can be five feet to the vent.
The shower can have the lav above it,
Or you can have the shower above the toilet trap arm.

 

[Sponsor]

 

[sprusgoose]

Thanks for the response Terry. After some further destruction of walls, etc., I've discovered that I was off on my drawing. I've attached a picture of the proper existing layout here:

The blue branch is the proposed shower - it would be wet vented below the kitchen and bathroom sinks - is this still acceptable? The 2" line is vented up to the ceiling then tied in horizontally back to the 3" stack. I would still be within 5' of the 2" vent stack with my shower drain. All help is appreciated. Thanks!

 

[Terry]

A kitchen sink can't wet vent over the shower.
A bathroom lav can.

Add a second second wye off the 3" waste line and tie the two vents together at 42"
The kitchen sink isn't supposed to wet vent over the lav either. A sink when it drains is a lot more volume of water then what a lav puts out.

 

[sprusgoose]

Hopefully the 3rd time's a charm....how does this look:

Does the order the wye's fall in, make a difference? Thanks again for your help.

 

[sprusgoose]

Edit: Sorry, wrong forum!