Maximum Standpipe Height

[BigAl]

I have the problem of a home with a slab and pipes in the slab being too small to handle modern washing machines that power massive amounts of water volume through the stand  pipe.  With not enough gravity space for volume discharge, the stand pipe overflows.  We bought a front loading energy star washer that used a lot less water but my wife didn't like the way it cleaned even though it was the best you could buy.  

I had put a larger stand pipe in to help fix the problem before buying the LG but it wouldn't hold the standard washing discharge.  I can't put a larger pipe in wall because of space.  Wife does not want a sink in the laundry room, so I decided that tomorrow, I'm going to get a sewer pvc pipe, and elbow(s) to tie into the line going to the pea trap.  Use enough adapters or rubber to attach the large pvc pipe to the drain as the new stand pipe.  It will hold the max amount of water the tub will have at any given time so discharge would never overflow the stand pipe.  It would act exactly like a sink with out the sink.

What do you folks think?

[Jim Katen]

I think you're addressing the symptom, not the problem. 

Contrary to your statement, modern washing machines discharge less (far, far less) water than older washers. If the new LG washer is causing the drain to overflow, its either because the drain is corroding on the inside and needs to be replaced, or because the person using the washer is putting too much detergent into it. Modern HE washers need a tablespoon or so of detergent. If you use the same amount that you used to use in an old top loader, you'll produce waaaay too many suds, which will choke up the drainpipe. 

Really, I can't stress this enough, use just a little bitty bit of detergent with any modern HE machine. 

As for your proposed solution. I have no idea what you're talking about. You say that you already put a larger pipe in, but that the wall won't let you put a larger pipe in, but you're going to put a larger pipe in. ???

How old is your house. What kind of pipe serves the washer?