Drain pipe stub too low for new vanity

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edee_em

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The vanity that is meant to fit in front of this plumbing (see pic) is a tall model with an open bottom cut out so one can put baskets, towels etc. under there. That means that the the bottom of the cabinet is about a foot to a foot and a half above the floor. The drain pipe in the photo rubs up against that so the drain pipe stub out is about an inch too low as is for this style cabinet. There is a cut out in the bottom to accommodate the p-trap plumbing.

I was wondering if I could raise the drain pipe stub and then 45 degree it down to the existing horizontal drain pipe going off to the right. If not, the option is to replumb everything or cut the cabinet in some fashion. Thoughts? Thanks.
 

Twowaxhack

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I’d either cut the cabinet or raise the tee in the vertical pipe then extend a new horizontal drain to the lavatory.

Any other way you’d need to add studor type vent..
 

Duckbutter

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Raising the height between the trap and vent will create an "S" trap, it will self siphon the way toilet traps do. You'd need to alter the height of the vertical tee the drain & vent connects to inside the wall.

Bath lav drains are installed @ ~18" off finish floor, standard vanities are supposed to account for that.

I see a lot of plumbing fixtures purchased online that don't factor standard plumbing dimensions, resulting in having to cut into them to make them work.
 

edee_em

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Raising the height between the trap and vent will create an "S" trap, it will self siphon the way toilet traps do. You'd need to alter the height of the vertical tee the drain & vent connects to inside the wall.

Bath lav drains are installed @ ~18" off finish floor, standard vanities are supposed to account for that.

I see a lot of plumbing fixtures purchased online that don't factor standard plumbing dimensions, resulting in having to cut into them to make them work.
Thanks Duckbutter. The main issue I have is that the lav drain is not installed 18" off the floor. Close but not quite 17" to center. Also, yes, new vanities are higher and don't take into account older lav drain heights. Ah, the joys of living in an older home...
 

Riickk

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The wall is open so you can adjust the drain pipes, with some effort.
If it were me, I'd likely just make room in cabinet bottom. Sure you're going to see it when you're looking for a fresh roll of paper, but will you care? for that matter, will a potential buyer care? (No.)
 

edee_em

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The wall is open so you can adjust the drain pipes, with some effort.
If it were me, I'd likely just make room in cabinet bottom. Sure you're going to see it when you're looking for a fresh roll of paper, but will you care? for that matter, will a potential buyer care? (No.)
What's the best way to raise that tee on the vertical drain, ferncos? Cutting the vanity is an issue, for now, as the drain pipe is being stopped by the bottom of the vanity cabinet which is where the support for the carcass of the cabinet is. There is a cut-out in the bottom of the vanity but I need to get the drain pipe up enough to get over that edge.
 

JG plumbing

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It's not an old rough in. There is a standard height and manufacturers are making them out of standard spec. This is getting to be common. People want different things as time goes on. A brand new house would probably have about the same height drain.
 
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