Upstairs Laundry over downstairs laundry tie-in

[Brandon Dean]

Hello. I'm a DIYer. We are moving our laundry room upstairs. It is essentially being moved directly above where it currently is downstairs. I'm thinking about simply extending the standpipe below up to the second level.

1. Is that a good idea?
2. Is the existing p-trap (on the first floor) sufficient for this, or do I need to add one upstairs as well?
3. How high up from the second floor does the stand pipe need to be? (The wall upstairs is short due to a barn style roof.)

Is there anything that I am not thinking of?

Details: we are in Gwinnett County in Georgia. We have a front loading washer.

 

[wwhitney]

Standpipes are limited to a height of 18" to 42" above their traps.

Chapter 8 Indirect/Special Waste: Indirect/Special Waste, Georgia State Minimum Standard Plumbing Code | UpCodes

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So you will need to install a new trap upstairs, along with a new standpipe and a vent takeoff on the trap arm of the new standpipe. The dry vent can join the existing dry vent (assuming there is one) for the standpipe below as long as it occurs at an elevation at least 6" above the standpipe flood rim. Or you could use an AAV for venting the standpipe trap.

The existing trap downstairs should be removed. The new drain line from the upstairs trap may connect to the existing downstairs drain, possibly even at the former trap arm.

Cheers, Wayne