DWV Setup/Suggestions With SketchUp

[PM5K]

So basically we have an 8x8 bathroom. There was a space for a tub but we've decided against it as it's a second bathroom. The sink is on one wall in the middle, while the toilet is on the other wall, just off from the middle (3 1/2 ft). The sink has a 2 inch drain/vent and the toilet has a 3 inch drain. The main line to the septic is 3 inches, and is basically in the corner as shown.

There are already some connections down there but I've been told on this forum that at least a couple of the connections/fittings are wrong, and the connections were never even completed (neither the toilet or the sink connect to each other or to the main drain line).

So I've decided to start from scratch underneath. Any suggestions would be appreciated, the more specific the better, including what fittings to use.

TIA

 

[Terry]

The 3" can continue to the wc, with a 3x2 wye for the lav.
The lav and it's vent will continue to be 2", with a 2x1.5" santee set at 18" or 20" from the floor depending on the pedestal dimensions.
Normally I like to offset to the side of the pedestal so I can install wood blocking behind, and arm over for the drain.

 

[Sponsor]

 

[PM5K]

Hey Terry, thanks for the response.

A few questions:

I've attached a SketchUp below, should I use the fitting as shown at the bottom of the WC and put a cleanout on the end, or should I just use a long sweep 90? As it is now it uses a wye on its back which I was told was wrong so I was planning to cut it off and start over.

Also, the WC line and the main drain line are offset from each other by about 6 inches from the center of one pipe to the center of the other, again as shown. Are there any particular fittings I should or should not use to connect them?

I'm assuming this will work as a wet vent?

 

[Terry]

A wye on it's back is fine.
A santee on it's back is not. You have a santee in the picture.

The lav wet vents the toilet.
It should have a wye fitting, then a long turn 90 where it bends up toward the lav.

 

[PM5K]

A wye on it's back is fine.
A santee on it's back is not. You have a santee in the picture.

The lav wet vents the toilet.
It should have a wye fitting, then a long turn 90 where it bends up toward the lav.

Okay. In the SketchUp I have a long sweep tee wye. Is that not the correct fitting for under the WC? Should I add a cleanout on whatever fitting I use under the WC? I'm assuming yes since you said I should use a wye under the WC.

 

[Terry]

What you have under the toilet is fine.
For the offset, you can use 22's or 45's