How to add double vanity sink plus a drinking fountain just outside the bathroom with one 2" drain

[James Simonsen]

I am finishing a basement and want to have a double sink vanity in the bathroom and a drinking fountain just outside the bathroom. The configuration is drain then 18 inches to the first sink then 3 feet to the second sink and then an additional 2 feet to the drinking fountian.

I am planning on putting an elbow on the drain and then putting a tee in between the double vanity. The question is what type of tee do I use between the sinks and then can I just continue the line to the drinking fountain. I understand that I would connect the pipe between the sinks and the pipe gong to the drinking fountain up to the vent pipe.

Thanks for any input you may have to help me make sure all three drain well.

 

[wwhitney]

Does the drinking fountain drain get plumbed with a regular 1-1/4" or 1-1/2" tubular trap like a lavatory? I'll assume so.

If all three traps are at the same elevation (within 2" and can be adjusted as required), then a horizontal wet vent would be a simple solution. From the existing drain going upstream, you'd have: horizontal 2" drain - 2 x 2 x 1-1/2 flat combo for sink #1 inlet - horizontal 2" drain - 2 x 1-1/2 x 1-1/2 flat combo for sink #2 inlet - horizontal 1-1/2" drain - upright 1-1/2" combo for vent takeoff - drink fountain inlet.

The one vent takeoff between the two upstream most fixtures serves to vent all three.

Cheers, Wayne

 

[Sponsor]

 

[James Simonsen]

Does the drinking fountain drain get plumbed with a regular 1-1/4" or 1-1/2" tubular trap like a lavatory? I'll assume so.

If all three traps are at the same elevation (within 2" and can be adjusted as required), then a horizontal wet vent would be a simple solution. From the existing drain going upstream, you'd have: horizontal 2" drain - 2 x 2 x 1-1/2 flat combo for sink #1 inlet - horizontal 2" drain - 2 x 1-1/2 x 1-1/2 flat combo for sink #2 inlet - horizontal 1-1/2" drain - upright 1-1/2" combo for vent takeoff - drink fountain inlet.

The one vent takeoff between the two upstream most fixtures serves to vent all three.

Cheers, Wayne

So what kind of tee should I use between the sinks to continue on to the drinking fountain? Because the drinking fountain will be 4 feet between the trap and the vent don’t I need a separate vent pipe for the drinking fountain?

 

[wwhitney]

Sorry, you've lost me on the layout. From the OP, I took it to be 3 fixtures in a line, existing drain, then sink, sink, drinking fountain, with 2 feet from the drinking fountain to the closer sink. If it's something else, a drawing would be in order.

Does the drinking fountain trap have to be several inches higher than the two sink traps? If so, that would require a different layout than I suggested.

Cheers, Wayne