Kitchen sink piping help


  #1  
Old 10-03-20, 04:22 AM
B
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Kitchen sink piping help

Hi

I have remodeled our kitchen and now at the stage of getting the waste pipes installed. Below are pictures of how the old pipes were run. Basically 1 1/2" pipe dropped down through floor in sink cabinet into basement and then went across diagonally to connect to the pipes you see in the first pic. This connects to cast iron and then runs under the floor to connect to the main drain 15ft away. How should I reconfigure this to make it a better system.


Should I have the pipe come from the sink going diagonally like it did to the current stack or should I run the pipe parallel to the joists first then have 90 elbow over. Concerned about the 90 elbows and if that would make things worse.


I would also like to upsize to at least 2" but the cast iron fitting looks like it reduces to 1 1/2 for the current pipe. So my 2" would be draining down into 1 1/2" cast iron fitting and then under the floor which I believe is 2 or 3". I am guessing I would have to dig up that cast iron and switch the fitting out?


Also looking to reconfigure that stack. It has a p trap that collects the condensate from boiler. Another condensate drain from the water heater drains into the open pipe as seen in first pic.


A lot of info I know, but hopefully someone can point me in the right direction. Thanks. Brian





Pipe from kitchen sink going down to floor




Panoramic of pipe from kitchen sink( has been cut from sink half way during remodel)
 
  #2  
Old 10-03-20, 04:58 AM
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I'm not sure if I understand your question correctly but there is no requirement that drain pipes be on nice 90° and parallel to the joists. If you get better fall or can reduce the number of fittings (especially 90's) then I'd go diagonal.
 
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Old 10-04-20, 07:30 PM
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I don't see any issue with it. I would install a wye and cleanout where you go vertically through the floor. The combo wye will be a longer bend, and the cleanout will help if you end up with any grease buildup or clogs down the road.
 
  #4  
Old 10-05-20, 04:39 AM
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I do not see anything wrong with the set up.

Though you said the pipe dropped down through the floor and did not mention a trap which you need.
 
 

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