Double Vanity Alternative Rough In Layout

[MNeeseSpokane]

Hello, this forum has been exceedingly helpful for me. One question I have as I rough in a basement bathroom, is whether the following double vanity rough in layout is acceptable.

I drew my understanding of the traditional layout that I would prefer (Option A), but due to the space constraint below, it isn’t a great option.

Constraint: since this is in the basement, the drain needs to go horizontally through through the wall to get to where it drops into the waste line under the concrete. The horizontal pipe is already about 16” off the ground, so with a standard 90 and double fixture fitting, I’m getting close to 23/24” off the ground for height of stub out, which may be cutting it close with my vanity.

With option B attached here, i can stay closer to 18”-20” off the ground, as long as it is allowable. Does option B seem acceptable? “H” on the diagram is the variable I am concerned about.

I’m under UPC in Washington. Thanks in advance!

 

[Terry]

Either A or B works.

 

[Sponsor]

 

[wwhitney]

I don't see how option B reduces the height H very much. You have several options (from right to left)

H=0: 1-1/2" flat LT90 for right stubout; 2 x 1-1/2 x 1-1/2 vertical combo for dry vent take-off ; 2 x 2 x 1-1/2 flat combo for left stubout (wet vented).

H = more: 1-1/2" street san-tee at a 45 for right stubout ; 45 to go horizontal; then 2 x 1-1/2 x 1-1/2 wye with a street san-tee in the branch for left stubout

H = somewhat more: same but LT90 instead of 45, and combo instead of wye.

Cheers, Wayne

 

[MNeeseSpokane]

Terry, thanks for responding so quick. Much appreciated.

Wayne, that idea with the wet vent and horizontal combo is nifty, I did not think of that! Unfortunately I started gluing once I had Terry’s “blessing.” Just in case you were curious, the H difference between “A” and “B” that I had drawn was 8” down to about 5”. This gets me low enough that I’m comfortable with the height. This darn double fixture fittings are just tall.

If I run into an issue with mine, I’ll circle back and switch to your better solution—I just would have to re-drill studs, waste fittings, etc.

Thanks again to everyone who contributes here!

Mike