Kitchen drain rough in just a little too high

[Steve Zerby]

I’m installing a double-bowl kitchen sink with a dishwasher inlet and the drain rough-in is about 3/4” too high for the p-trap outflow when I make the flanged DW tailpiece as short as it can be and then add the side inlet piece for the other sink bowl.

I saw the post here about the reversing p-trap that Dearborn makes but would prefer to keep the chrome setup if possible. Any suggestions?

I could cut the flange off the DW tailpiece and push it up further into the strainer outlet as a slip joint instead of a flanged joint. Is there anything wrong with trying that?

Are there shallower strainers with a shorter outlets? These seem to have very long outlets.

Thanks,

Stev

 

[wwhitney]

I'm not very familiar with the slip-joint tee fitting you show, but assuming you have it in the correct orientation, you can cut its tailpiece shorter, so that there is less pipe showing between the tee portion and the trap inlet. Of course, you'll have to coordinate the height of the tee side inlet with the horizontal drain coming from the other sink.

Modifying the flanged connection at the sink strainer is not a viable option. Looking for a flanged tailpiece with a higher dishwasher inlet is a possibility, although I don't know if they exist. I have seen pictures of double kitchen sinks where the dishwasher inlet is on the horizontal drain going into the tee; not sure if that is advisable.

And just to double check, all the horizontal piping under the sink needs to have 1/4" per foot slope downstream.

Cheers, Wayne

 

[Sponsor]

 

[Steve Zerby]

I'm not very familiar with the slip-joint tee fitting you show, but assuming you have it in the correct orientation, you can cut its tailpiece shorter, so that there is less pipe showing between the tee portion and the trap inlet. Of course, you'll have to coordinate the height of the tee side inlet with the horizontal drain coming from the other sink.

Modifying the flanged connection at the sink strainer is not a viable option. Looking for a flanged tailpiece with a higher dishwasher inlet is a possibility, although I don't know if they exist. I have seen pictures of double kitchen sinks where the dishwasher inlet is on the horizontal drain going into the tee; not sure if that is advisable.

And just to double check, all the horizontal piping under the sink needs to have 1/4" per foot slope downstream.

Cheers, Wayne

If I cut that t-fitting as short as I can I still wind up too low by about 3/4”. I can reverse the j-bend like the Dearborn plastic one does, but then there is very little tailpiece going into the inlet side of j. See photo.

Why would making the strainer connection a slip fitting not be viable? It is physically possible. Too leak prone?

 

[Tuttles Revenge]

There is a Poly fitting that is the Tee and Wye in one fitting.

 

[Tuttles Revenge]

In keeping the chrome setup.. .there are much shallower basket strainers out there. That would likely net you the 3/4" you need.

Perhaps even the WYE branch on the horizontal span between sink bowls, as long as its baffle doesn't become an obstruction.

 

[wwhitney]

If I cut that t-fitting as short as I can I still wind up too low by about 3/4”

So I think what you are saying is that if you take your wye branch flanged tail piece, and line up the tee so the top of it is just below the wye branch, then the bottom of the tee portion is below the inlet of the p-trap? Then I agree that's not going to work. You'll either need a new wye branch with a higher inlet, a shorter strainer basket, or to use a horizontal wye branch.

Why would making the strainer connection a slip fitting not be viable? It is physically possible. Too leak prone?

Good question. I think the answer is that vertical slip joints always have a plain end sticking down, fitting into the oversized cup shaper receiver below. While what you propose would make that upside down. If you stuck the plain end too far up, you'd make a space where water couldn't drain, just outside the tubular pipe. And if you avoid that, then your slip joint connection will have basically no overlap, and it would be unstable.

Cheers, Wayne

 

[James Henry]

Just install a shallow strainer, you'll gain 2 inches. It's that simple.

 

[Steve Zerby]

So I think what you are saying is that if you take your wye branch flanged tail piece, and line up the tee so the top of it is just below the wye branch, then the bottom of the tee portion is below the inlet of the p-trap? Then I agree that's not going to work. You'll either need a new wye branch with a higher inlet, a shorter strainer basket, or to use a horizontal wye branch.



Good question. I think the answer is that vertical slip joints always have a plain end sticking down, fitting into the oversized cup shaper receiver below. While what you propose would make that upside down. If you stuck the plain end too far up, you'd make a space where water couldn't drain, just outside the tubular pipe. And if you avoid that, then your slip joint connection will have basically no overlap, and it would be unstable.

Cheers, Wayne

Thanks

 

[Steve Zerby]

In keeping the chrome setup.. .there are much shallower basket strainers out there. That would likely net you the 3/4" you need.

Perhaps even the WYE branch on the horizontal span between sink bowls, as long as its baffle doesn't become an obstruction.

Thanks.

 

[Steve Zerby]

Just install a shallow strainer, you'll gain 2 inches. It's that simple.

Thanks.

 

[Steve Zerby]

Just install a shallow strainer, you'll gain 2 inches. It's that simple.

 

[Steve Zerby]

Just install a shallow strainer, you'll gain 2 inches. It's that simple.

Thanks!

 

[Steve Zerby]

Update: I got shallower strainer baskets. Not great quality, but I gave the client the option of better baskets and plastic plumbing or shallower baskets and metal drains. She chose metal drains. Had about 1/8" to spare.

 

[Jeff H Young]

Looks good The wye branch tailpiece ate up a lot of height. I had that issue before