Another Double Vanity Question

[kybob]

I'm in the process of converting a single to double vanity. My initial plan was to use a double santee (with cleanout above!) but am realizing the existing bored holes/notches are quite low (~15") and I am planning to install a floating vanity.

This is not a load bearing wall but still it seems silly to bore/notch right above the existing. Instead I was thinking of having an individual vent. Am I overthinking this and should just go with the original plan or does the seperate vent make more sense?

 

[John Gayewski]

I like the simplicity of using a Double fixture fitting instead of reventing. Mainly because it's less work and looks better and leaves more space for hanging mirrors or cabinets above without hitting vent pipe.

Using a double sanitary Tee isn't generally good, but with a cleanout above it should be fine. I think I'd still go with a double fixture fitting though.

 

[Sponsor]

 

[Tuttles Revenge]

A lot of times in floating vanities we end up stubbing out around 19-22 Above Finished Floor (AFF)..

I agree with John, that your best installation is a fixture cross. You will only be drilling 1 hole with the fixture cross if you maintain the same bored drain hole, or be drilling the same number if you raise it up and drill each trap arm at the needed height.

Ultimately both scenarios work.

*When I layout for floating vanities, we start from the finished height of the cabinet, deduct for the counter surface(typically 3cm stone), deduct the height of the sink(typically undermount),take the type of drain assembly into consideration(typically a push-pop up), then figure if we're installing a P-Trap vs a Bottle trap. Using all of those known heights we can come up with a really tight installation where the entire plumbing is inside a very small floating vanity (cuz our designers either hate us or know we know how to deal with their wakadoodle designs)

 

[kybob]

A lot of times in floating vanities we end up stubbing out around 19-22 Above Finished Floor (AFF)..

I agree with John, that your best installation is a fixture cross. You will only be drilling 1 hole with the fixture cross if you maintain the same bored drain hole, or be drilling the same number if you raise it up and drill each trap arm at the needed height.

Ultimately both scenarios work.

*When I layout for floating vanities, we start from the finished height of the cabinet, deduct for the counter surface(typically 3cm stone), deduct the height of the sink(typically undermount),take the type of drain assembly into consideration(typically a push-pop up), then figure if we're installing a P-Trap vs a Bottle trap. Using all of those known heights we can come up with a really tight installation where the entire plumbing is inside a very small floating vanity (cuz our designers either hate us or know we know how to deal with their wakadoodle designs)

agreed on the one hole piece but this is already bored out at 15” which is really low. To stub out higher I would be boring another hole in each stud.

 

[Tuttles Revenge]

15 inches is just an old standard height for old 30" tall vanities with lots of room. If that height works for your floating vanity to not have the trap stick out the bottom, and drilling extra holes in non load bearing studs is a concern, then I would go for it.

But if the trap sticks out or you have to modify the cabinet just because of the height, I would re-drill at the height needed for a cleaner look.

 

[pritchardsplumbing]

Given your situation, it might be wise to go with the separate vents. This way, you avoid compromising the wall further and ensure each sink has adequate ventilation. It might require a bit more work initially, but it could save you headaches in the long run.

Using a double santee with a cleanout above is a common approach, and it generally works well. However, if the existing holes and notches are too low for your floating vanity, it might not be the best fit.