Plumb W/D

I'm going to be moving my W/D up to 2nd floor and using 1/2" Pex, a couple of Sharkbites couplings & Webstone fittings for the plumbing part which I found at Houseneeds.com. My question is: How do I go about extending the washing machine drain? Does it need to run straigt down to the basement or can it elbow to a long horizantal run before elbowing down to the exhisting PVC drain?

Thanks for any help!

You need the proper standpipe height, and a trap. Then you can run it down almost any way you want as long as you maintain a minimum of 1/4" per foot. I think that you'd need to re-vent it nearer to the new trap.

By 1/4" per foot you mean the slope?

proper standpipe & trap???

The washer drain needs to be 2". There is a vertical pipe (standpipe) above a trap that you hook the washer hose to. This needs to be a specific height (don't remember now, but you can search and find it). You need a trap below that standpipe otherwise, any soap scum in that 10-15' or more of pipe will be open to the bedrooms and smell eventually. The trap isolates all that pipe run from the house.

Yes, that 1/4" per foot is the slope. Any near horizontal lines need that slope or more.

it can be 1 1/2 do a 30 inch standpipe TY, trap and tie the vent in the attic.

Today's code, as I understand it, requires 2". Using less risks overflow from today's high efficiency washers and pumps.