Clothes washer drain

[Sifu]

Is a clothes washer drain required to be 3" when it turns horizontal under the IPC?

 

[Gregg Harris]

Is a clothes washer drain required to be 3" when it turns horizontal under the IPC?

IPC 406.3 The automatic cloths washer fixture drain shall be connected to a branch drain or drainage stack a minimum of 3 inches.

 

[Sifu]

The code I enforced in one of my previous jurisdictions specifically stated the word horizontal. The IPC does not. Nobody around here does it so I am again trying to figure out if its me or them. It was explained to me that when the drain turnes horizontal the suds can cause a back-up, especially with the newer high capacity washers, hence the 3" requirement. I typically see the standpipe down to the trap (lucky if its within 42" then turn horizontal and run several feet in 2" until it hits the building drain. In my last job as plumbing inspector this would have ben a no-go, here I can say I have never seen it done in 3".

 

[steveray]

i DO NOT SEE THAT REQUIREMENT IN THE IRC... but in the IPC...yes...