Replies

1. 
   plumbbill | Oct 05, 2005 02:38am | #1

   well more preferance than code on this one.

   Since most clothes washers back are 42" tall I usually put the bottom of the box at 42" so the valves & drain connections can be accessed.

   & code for the trap & stand pipe connecting to the box is as follows.

    trap serving a clothes washer standpipe shall be on the same floor not less than 6" above the floor nor greater than 18"

   the standpipe will be at least 18" but not more than 30"

2. 
   G80104 | Oct 05, 2005 02:39am | #2

     36 " to the bottom of the box will work.  Here is a picture for you.

   
1. 
   Jemcon | Oct 05, 2005 02:47am | #3

   But if code says not more than 30" to top of stand pipe then 36" is to high. So what's the right answer? But at 30" you couldn't reach the shut off valves behind the washing machine? Who can solve this problem. By the way, nice install. 

    

    

   Headstong, I'll take on anyone!

1. 
   G80104 | Oct 05, 2005 03:14am | #4

     Trap is about 8"-10" off the floor, bottom of the box is 36", makes the pipe 26"-28" long.

1. 
   TRIGGER | Oct 05, 2005 03:49am | #5

   I was recently gigged on that rule and our plumber had to raise the trap.

   Also,..................According to  Popular Mechanics Magezine.   "Early plumbers picked up their title from the name of the material they worked with most; plumbum- Latin for lead. Unfortunately, they didn't know it was toxic."

   How's that for a fun fact!

                    Please hold your applase, TRIGGER

   Edited 10/4/2005 9:03 pm ET by TRIGGER

2. 
   Jemcon | Oct 05, 2005 03:55am | #6

   Got it. I thought the pipe couldn't be more than 30" off the floor. Thanks. 

    

    

   Headstong, I'll take on anyone!

3. 
   Frankyh562 | Mar 05, 2021 06:43pm | #7

   There’s lots of confusion on this specific code height and as a union plumber who studies code I can confirm that the Local “California”code states the P-trap needs to be 6”-18” on center off Finish floor and from the (CENTER) of the trap the standpipe can rise 18”-30” above that. So if your trap is at 6” you can run a standpipe 30” above center of trap which leaves top of standpipe at around 36”... just giving multiple examples. That Center measurement off the trap is huge and people don’t quite understand that part. That’s why 6” is minimum trap height because the max standpipe height above that is 30” putting you around 36” above finish floor and being heigher than 34” flood level of a sink or anything downstream in case of a backup it won’t spill out the standpipe