washing machine drain-p trap info

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by crazycraig68, Dec 13, 2009.

  1. crazycraig68

    crazycraig68 New Member

    Messages:
    5
    Location:
    Marietta, GA
    Hey Y'all from Marietta, GA. I am not real good with explaining things so please don't think I am stupid, just try and help me out.

    my washer used to be in the kitchen of my 50's ranch house. I have a large crawlspace under the house so things are real easy to work on. The washer is currently in the carport area storage room where it was when the house was built. So, it currently drains into 2" pvc pipe into concrete slab, then goes through the block foundation and into the main drain line just before the kitchen sink. No p trap obviously and it drains just fine with no problems. there is a small vent thing off the side of the drain pipe and i think they call it a studor vent? There is a big cast iron vent pipe right at the kitchen area so that could be the reason it all drains so perfectly. Now, here is what I am wanting to do.....again.

    I want the washer back in the kitchen as it's just so nice to have it in the house. When it was moved from kitchen to outside a couple years ago, i remember the plumber telling me that he capped off the supply lines in the crawlspace, and where the drain line went into the main drain line, he capped that off as well. Are y'all with me so far? GOOD! I never looked at how it was once the 2" pvc was after it went through the kitchen floor. I mean from the washer box mounted on the wall to the floor is a bit less than 4'. If you allow the thickness of subflooring then once the pipe was into the crawlspace, we are looking at 4.5'. My BIG question is, once the pipe gets into the crawlspace, is that where I should put a p trap? I know how to do a lot of plumbing stuff and I just dont remember where or if the plumber used a p trap before. There is about 4' of pipe that would be going from p trap to where it ties into the main line and I know I will have to use some pipe and elbows and such to get the angle just right. From where the washer will tie into the main drain, the vent is less than 2' away. So, please tell me if its ok to have ptrap 4.5' down, then just angle the pipe to where it connects to the main. If I don't need a p trap, tell me that too.

    I am very excited about getting this done, so please feel free to give me any advice y'all have. I know it's hard to understand the way I described it, but I hope someone can.

    Thank you so much.

    Craig
  2. export!

    export! DIY Member

    Messages:
    90
    Location:
    Ontario, Canada
    If the washer box was done correctly in the first place there is probably a trap in the wall between the box and the floor.

    Uncap the original 2" drain pipe under the house if it is capped. Pour some water into the laundry drain box. Snake something down the drain. If it only goes a few feet before meeting some resistance and comes up soaking wet I'd say you have a trap.
  3. crazycraig68

    crazycraig68 New Member

    Messages:
    5
    Location:
    Marietta, GA
    original poster

    the washer box was removed, as it was only screwed on the knotty pine wood that covers the kitchen walls. nothing was ever in the wall, and like i mentioned, it was capped off where washer drain goes into the main drain in crawlspace. my questions were if it would be a big deal if p trap was 5' from where washer hose goes into pipe. i dont really have a choice. all other plumbing is like new, so no need to snake or try to clean anything. i just have to run standpipe down, do p trap, and then turn the pipe heading towards the main drain.
  4. WorthFlorida

    WorthFlorida USCG escorting cruise ship leaving Port Everglades

    Messages:
    117
    Location:
    Lake Worth, Florida
    You would want the p-trap above the main waist line connection. This will minimize waste water from ther main line to getting backed up to the washing machine p-trap. You want clean water from the machine to remain in the trap and not waste water perhaps from a toilet. You still need to be properly vented and from your explanation it might be OK as is?
    Last edited: Dec 14, 2009
  5. jetlag

    jetlag New Member

    Messages:
    84
    Location:
    Ga.
    washer trap

    Im from Ga too. The washer stand pipe can be no less than 18" and no more Than 42" above the trap weir ( thats the water level that stands in the trap)
    The 4.5 feet is to much to put the trap under the house. You have 2 options , drop the box to 34" (thats the min) and you will have 8 more inches to get th trap in under the house. Or you can put the trap inside against the wall near the floor and come up 18 to 42 and mount the box. But it has to be above the washer flood level of 34". Also if you put the trap inside you cant use an 's' trap an more they are not allowed. You must use a 2" glue type p trap come over horizontal a min of 4 " then 90 down thru floor
    Last edited: Dec 14, 2009
  6. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,835
    Location:
    Cave Creek, Arizona
    drain

    You cannot have a washer riser that long, and the trap SHOULD be above the floor. You DO need a vent of some kind. From your description you are trying to make an easy installation of a drain that "works", not one which is installed properly.
  7. Terry

    Terry Administrator Staff Member

    Messages:
    15,130
    Location:
    Bothell, Washington
    There is a limit as to the length of a standpipe.
    Too long and it siphons the trap.
    That is why code insists that the p-trap be above the same floor that the washer is sitting on.

    The p-trap must be vented within five feet of the trap.

    No standpipe shall extend more then 30" or less then 18" for a washer.

    [​IMG]
    Last edited: Dec 14, 2009
  8. nukeman

    nukeman Nuclear Engineer

    Messages:
    711
    Location:
    VA
    While we are on the subject, my washer standpipe goes below the floor (basement) and is not vented. :( I am going to fix the venting issue. Should I relocate the p-trap? The floor is concrete and the wall is cinder block.
  9. Terry

    Terry Administrator Staff Member

    Messages:
    15,130
    Location:
    Bothell, Washington
    It would work best if you did.

    The codes are basicly books on what has been found to work.
    Go beyond the code, and you dip into the area that has been causing problems.
  10. nukeman

    nukeman Nuclear Engineer

    Messages:
    711
    Location:
    VA
    Thanks, Terry. I guess would mean attaching the plumbing to the cinderblock wall. I also need to run down and under this wall as the 4" main line runs horizontally under the slab on the other side of the wall. The washer drains okay, but goes "glug glug" when draining. You also hear it in the floor drain. Hopefully, the venting will help out.

    Sorry for the threadjack. I'll start my own thread if I have more questions. Good luck. :)
  11. Terry

    Terry Administrator Staff Member

    Messages:
    15,130
    Location:
    Bothell, Washington
    That glug glug glug is the trap siphoning.
  12. nukeman

    nukeman Nuclear Engineer

    Messages:
    711
    Location:
    VA
    Yeah. I can't believe any of this was code at any time. The city knows that the basement is finished, so I assume the plumbing was inspected. In fact, I believe it all to be original to the house (~40 years old).

    crazycraig: Sounds like these guys have you covered. I'm sure Terry's pic will help a bunch. :)
  13. crazycraig68

    crazycraig68 New Member

    Messages:
    5
    Location:
    Marietta, GA
    you cannot tell what i am describing is proper? sorry.

    i guess the point of my post is that i will be able to put the pipe in the kitchen 36" above the floor as it is now hooked up. then i can put the ptrap right under the floor in the crawlspace, then on to main drain. According to other posts on this site, 36" above the floor is correct and ptrap is within the correct measurements as stated on here as well.

    that vent must work as i have never had a problem? where it is now it is before kitchen where the original house vent is. in my pics you can see the cast iron vent coming down and merging into the main drain line that is now pvc. There never was a vent of any sort in that small room for over 50 years and things worked great, but my plumber who put the vent on that pipe said there needed to be some venting at that location per code in this county. this was a licensed plumber out of atlanta that has worked on many houses in this area for 30+ years. If i havent had any problems, how do i know if it really works or not right?
  14. nukeman

    nukeman Nuclear Engineer

    Messages:
    711
    Location:
    VA
    Craig,

    Can you post some pics? I am noit sure if GA is under the IPC code. If so, the washer is suppose to have a 2" trap/standpipe and then go into a 3" or larger stack or horizontal branch. Most will agree that the 3" is overkill and 2" works fine. I am having to do the 3" stack as VA is under IPC. Just a heads up.
  15. crazycraig68

    crazycraig68 New Member

    Messages:
    5
    Location:
    Marietta, GA
    thanks y'all for your advice. just got a new puter and forgot about this thread as i couldnt find it when i first tried.

    i checked where washer is now and the plumber put the top of the drain pipe right at 36" above the slab. it also has a tiny vent off the pipe as you can see in the pic. so, i think what i will do is, use this piece of pipe with vent going through floor to the crawlspace. I will put on the p-trap. then coming off the p-trap will be about 8" of 2" pipe going horizontal then elbow it down where it will go right into the drain where it once was. the original vent coming down the wall to vent the kitchen sink, is about 4' from the ptrap and yes, the ptrap is higher than where the vent connects to main drain line. i will try to post 2 pics but if not, thats ok. i know it will work just fine. i was only going to use that little vent off the existing standpipe as an extra vent thing.
  16. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,835
    Location:
    Cave Creek, Arizona
    That Studor vent was a waste of time and money because it does ABSOLUTELY NOTHING where it is installed. We cannot tell if anything you intend to do is proper from your description.
  17. Terry

    Terry Administrator Staff Member

    Messages:
    15,130
    Location:
    Bothell, Washington
    Venting the standpipe does nothing.
    The standpipe is open at the top, and air can get in there.
    It's the p-trap that needs a vent.

    The vent goes between the p-trap and where it enters the main waste line to break the siphon.
    You could take the studor and install it within five feet.
    If you have a vent within five feet of the p-trap, that would work too.
  18. crazycraig68

    crazycraig68 New Member

    Messages:
    5
    Location:
    Marietta, GA
    thanks terry!

    i will have the top of the 2" standpipe 36" from floor, then the p-trap a few inches lower right inside crawl space, then about 2-3 feet of pipe going into main drain. right where the washer line is going into the main drain, is the original cast iron vent that goes up through wall and through roof, so it is certainly less than 5' from the p-trap. the plumber who had it in the kitchen a couple years ago did not do it correctly obviously, as the standpipe was 4' above floor then p-trap was still in crawl space which is another 6-8 inches, so the way i am going to do it is the correct way. cant wait to get started.....when it gets above 50 here. :)

    have a great weekend!

    i do have 1 more question. being the house vent is less then 5' from p-trap, but right at the same spot where the washer line goes into the main drain, wold it be ok if half way between the ptrap and main connection, i put that studor vent i have to make sure there is enough venting? not sure if that would make sense but thought i would ask.
    Last edited: Jan 23, 2010
  19. nukeman

    nukeman Nuclear Engineer

    Messages:
    711
    Location:
    VA
    Craig,

    I'm not sure if you saw my post on the previous page. The server got reset, so some of the posts got out of order.

    Here, under IPC, the standpipe is allowed to go as tall as 42". I'm putting mine in at 30", though.
  20. lightmark

    lightmark New Member

    Messages:
    5
    Location:
    oceanside ca
    Venting in photo

    Why the take off on vent, is the 1 1/2" vent not sufficient for both washer and tub?

    [​IMG][/QUOTE]
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