View Full Version : Standpipe trap location
The inspector says that the 2" trap for the washing machine standpipe is not low enough to the floor. She wants it to be 18" or less to the bottom of the trap--it presently is 24" Is it code to put the trap under the house? This would make it a lot less than 18" The laundry is in the garage so lowering the trap involves cutting joists, blocking, and sole plate.
BAPlumber
03-19-2008, 11:42 PM
your question is kind of confusing. the opening to the standpipe should be on the same floor as the ptrap. the trap should not be below the floor. Without looking at my code book, the length of stand pipes are 18-30" above the trap.
Winslow
03-20-2008, 01:50 AM
According to the UPC the weir of the trap should be between 6"-18" of the floor. The standpipe is between 18"-30".
Mikey
03-20-2008, 05:13 AM
Why does the number 42" come to mind when talking about washing machine standpipes?
Because you are confusing it with the minimum lateral vent measurement. A standpipe that is too long will be subject to inertia trap seal loss.
Mikey
03-20-2008, 10:45 AM
Yup, that too, but:
Each standpipe shall be trapped, and the trap shall be a minimum 2"
Each standpipe shall be installed a minimum of 18" and a maximum of 42" above the trap.
The trap must be installed above the floorAt least that's what they want in Abilene, TX. I knew there was a 42 in there somewhere. (not that I might be confused as well :confused:)
One alternative suggested by the inspector is to build a 6" platform, floor, in the garage. This will then make the trap 18" off the "floor". It will also make it a little more difficult for a short person to unload a top loader WM, but easier to unload a front loader.
Mikey
03-21-2008, 07:02 AM
One alternative suggested by the inspector is to build a 6" platform, floor, in the garage. This will then make the trap 18" off the "floor". It will also make it a little more difficult for a short person to unload a top loader WM, but easier to unload a front loader.
If it's a FL washer, make the platform just big enough for the washer. If a TL, make it a BIG platform, so the short person can stand on it.
Why do they require the trap to be above the floor, anyway?
jimbo
03-21-2008, 08:02 AM
Is the garage floor somewhat lower than the wall footing? If that is the reason why it is so hard to lower the trap, how about moving the drain and standpipe to be outside of the wall framing ( on the inside of the garage). We see that a lot here. Newer homes, it is usually in the wall, but in the 60's and 70's, they just put the standpipe and trap right out in the open.
Winslow
03-21-2008, 09:55 PM
Why does the number 42" come to mind when talking about washing machine standpipes?
Maybe because if you put the trap at 12" (middle of the 6-18 requirement) then put a 30" stanpipe it measures 42 from the floor. Just an observation. This is also a good height in back of the washing machine, not too high as to be an eyesore and not too low to reach the valves.
Inspector wanted the trap enclosed by drywall. We cut out a 2x6 blocking and supported the floor under the house, then put the trap in the wall at 18" to bottom of trap. Standpipe is at 45" to top. Then ran a 1 1/2 vent to roof. Thanks to all for the help!!!!
Mikey
03-30-2008, 11:37 AM
Odd that an inspector would want something hidden; usually they're wanting access to something.