Is this p-trap design doable? diagram inside

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Patrick Mulligan

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So I am trying to install new, deeper sink, counter height is 34.5", sink is 10" deep, waste pipe is about 4' away and entry is 18"-20.5" off floor.

By my calculations, this will leave me roughly 4" for the sink strainer and trap. Can i bring trap up close to sink strainer? If I can I think I can make this fit with the proper pitch, but will it still work properly, and do you think this design is doable if I find a shallow strainer?

Thank you
 

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That’s how your are suppose to do it. Trap goes directly below entrance. Distance to existing connection might mess up your vent cause you a second longer drainage. But functionally it will work.
 
You can also use an all glue p-trap, scrap the street 90 for a regular 90. It gives you an extra inch or 2, makes a deeper wier, but it will still work
 
So I am trying to install new, deeper sink, counter height is 34.5", sink is 10" deep, waste pipe is about 4' away and entry is 18"-20.5" off floor.

By my calculations, this will leave me roughly 4" for the sink strainer and trap. Can i bring trap up close to sink strainer? If I can I think I can make this fit with the proper pitch, but will it still work properly, and do you think this design is doable if I find a shallow strainer?

Thank you
What exactly do these 2 points represent? 18"-20.5"? Distance to invert(bottom) or center line of pipe connection?
Why 2 points?
Also, you show 2" for 4 feet of slope.? 4 ft at 1/4"/ft = 1"

While I'm at it, I should probably mention, if you do go with elevating the traps exit elevation, as suggested to gain height, you must limit the total increase to 2" at the exit. Probably would amount to about an inch space between the hub ends of the trap and elbow. As others know, trap seal must be 2" min. and 4" max.
 
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I believe he's concerned with how much space he'll have left to fit the required items between the sink and the trap. Like sink strainer, tail piece and tail piece to trap adapter. Perhaps you can give him some ideas on how to minimize those requirements and allow the tail pipe to be removable without disturbing trap. I don't have much detail experience but I see they have a "Slip joint to trap adapter" which I guess has a spigot end to allow it to stick directly into the trap hub.
https://www.homedepot.com/p/NIBCO-1-1-2-in-PVC-DWV-Trap-Adapter-C480127HD112/100347086

This is my sketch I was playing with to confirm how much room he'd have.

That was based on a 4 foot trap arm at 1/4" per ft. with the connection point at the 18" height he had mentioned.
 

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you can gain some space by using pvc female adapter instead of typical desanco and tailpiece. thread right on to bottom of strainer. not ideal but it will work
 
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