(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 11 of 11

Thread: Undermount Sink and Garbage Disposal Potential Issue

  1. #1
    DIY Junior Member ms222's Avatar
    Join Date
    Aug 2012
    Location
    Florida
    Posts
    12

    Default Undermount Sink and Garbage Disposal Potential Issue

    I do not know much if anything about plumbing so bare with me please.

    So I am remodeling my kitchen and I'm on my last step. All of my cabinets are in. Moving the drain pipe is not really an option as the piping is in stucco/cinderblock and has an elbow that runs about 35" or more horizontally, so it would be a disaster.

    Here's the situation. I have a single basin undermount kitchen sink. The distance from the sink drain to the centerline of my in-wall vent drain is exactly 7". I currently own an insinkerator compact disposal, where according to manufacturer specifications, the distance between the sink drain and the centerline of the disposal discharge arm is 6". Instead of using a 90 degree arm from the disposal I would want to use a horizontal straight pipe to have the disposal discharge arm 1" higher than the in wall drain vent.

    My dishwasher is directly to the right of my sink cabinet.

    Below is my empty setup (sorry for picture quality).

    I am having a plumber come on Wednesday to install everything, can I get away with the disposal being 1" higher than the main drain, as technically water wouldn't have to travel upwards.

    If not, does anyone know of a disposal that has a smaller distance than 6" to the discharge arm? I looked all over and did not see any. Name:  plumbing.jpg
Views: 208
Size:  25.7 KB

  2. #2
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,374

    Default

    As long as the outlet of the disposer is above the inlet to the wall, a plumber should be able to make it all work. It's when the outlet is lower than the inlet in the wall where it is a problem.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  3. #3
    DIY Junior Member ms222's Avatar
    Join Date
    Aug 2012
    Location
    Florida
    Posts
    12

    Default

    The outlet based on my measurements will be 1/2" to 1" higher than the inlet to the wall. Hope this will suffice. How would my setup work if I used a horizontal straight discharge pipe in terms of it being able to hook up to the ptrap and not clog up?

  4. #4
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,602

    Default

    The problem will be getting the trap and disposer elbow to fit together within that 1" dimension, since the trap inlet is higher than the outlet pipe, and the disposer, or any other 90, will need some space for its radius. For compatibility reasons most disposers have the same dimension, other than batch feed models which are even lower. Even if you use a "horzontal pipe" it still has to turn downward at the trap.
    Last edited by hj; 12-09-2013 at 11:32 AM.
    Licensed residential and commercial plumber

  5. #5
    DIY Junior Member ms222's Avatar
    Join Date
    Aug 2012
    Location
    Florida
    Posts
    12

    Default

    Quote Originally Posted by hj View Post
    The problem will be getting the trap and disposer elbow to fit together within that 1" dimension, since the trap inlet is higher than the outlet pipe, and the disposer, or any other 90, will need some space for its radius. For compatibility reasons most disposers have the same dimension, other than batch feed models which are even lower. Even if you use a "horzontal pipe" it still has to turn downward at the trap.
    Is there anyway that a professional licensed plumber will be able to make this work? I just redid the kitchen and really dont want to have no disposal. At the same time, the drain pipe is so far away that moving it will tear up a lot of my brand new cabinets.

  6. #6
    Forum Admin, Expert Plumber Terry's Avatar
    Join Date
    Aug 2004
    Location
    Bothell, Washington
    Posts
    14,191
    Blog Entries
    1

    Default



    You may want to pick up a J Bend Low Inlet for your p-trap.


  7. #7
    DIY Junior Member ms222's Avatar
    Join Date
    Aug 2012
    Location
    Florida
    Posts
    12

    Default

    Hi Terry, thanks for your advice. Do you have a picture by any chance of a setup similar to mine that uses that pipe so I can visualize how it works?

  8. #8
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,602

    Default

    The problem with low inlet traps is that when the nuts are at the same "elevation", the inlet is almost as shallow as using a conventional trap "backwards". If you notice the one in the picture on the package has the inlet nut higher and it shows a "socket" for the tailpiece to slide into giving a more rigid and secure connection.
    Licensed residential and commercial plumber

  9. #9
    DIY Junior Member ms222's Avatar
    Join Date
    Aug 2012
    Location
    Florida
    Posts
    12

    Default

    Quote Originally Posted by hj View Post
    The problem with low inlet traps is that when the nuts are at the same "elevation", the inlet is almost as shallow as using a conventional trap "backwards". If you notice the one in the picture on the package has the inlet nut higher and it shows a "socket" for the tailpiece to slide into giving a more rigid and secure connection.
    HJ, I am not sure whether you are saying it will be just a challenge, or if it will not be possible. I understand this is less than ideal, but in all practicality, moving the drain pipe is out of the picture, and if it can be done, even if not as secure, I'm willing to take the chance.


    Anyone viewing this thread, please let me know if given the picture of my setup, and the 1" differential, if there is anyway to make this work? I am having a plumber come for $375 flat rate tomorrow, and don't want to end up having to settle on no disposal when he may try to tell me he can't do it because he is not up for a challenge that day. I just want to know if its theoretically possible to make this work, and maybe a picture or a diagram showing how to present to him. Thank you!

  10. #10
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,602

    Default

    Depending on how it is done, it could be less than ideal, but will work. "$375.00"? I would like to install them all day long for that price. Just don't come back tomorrow, like a previous poster" and ask if you got "taken" because he was only there 30 minutes.
    Licensed residential and commercial plumber

  11. #11
    TROJAN WORLDWIDE SALES RP MACPLUMB 777's Avatar
    Join Date
    Aug 2007
    Location
    Houston, Texas, United States
    Posts
    631
    Blog Entries
    1

    Default

    I think the poster was talking hooking up ever thing under the sink
    new faucet, supplies as whale as the g/d drain

    MACPLUMB 777

    E-MAIL
    JERRYMAC@TROJANWORLDWIDE.COM


    35 YEAR MASTER PLUMBER, HEATING, ELECTRIC, DRAINS, FIRE SPRINKLERS, WATER HEATER
    AND BOILERS SINCE JAN, 1989

    281-706-1631 7 DYS A WEEK SALES AND TECH. SUPPORT
    Trojan Worldwide Web Site


     



Similar Threads

  1. install garbage disposal in double sink
    By homey6660 in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 14
    Last Post: 10-06-2009, 07:35 AM
  2. garbage disposal overflow to other sink
    By boDoanh in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 8
    Last Post: 06-10-2009, 05:36 PM
  3. Double sink garbage disposal, which side?
    By GARMAN in forum Remodel Forum & Blog
    Replies: 1
    Last Post: 04-17-2008, 12:15 PM
  4. Garbage Disposal-Stone Sink
    By Richard'sRenu in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 3
    Last Post: 06-08-2007, 06:28 AM
  5. Reliable Kitchen Sink Garbage Disposal ??
    By florida_wen in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 11
    Last Post: 11-13-2005, 03:39 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •