Standpipe height

[Patflemming]

I know that the IPC states that the standpipe must be Not less than 18" but not greater than 42" above the trap.

Does the height of the standpipe compared to the height of the washer matter? In other words, can the standpipe be lower than the top of the washer, provided it's more than 18" above the trap?

 

[WorthFlorida]

I know that the IPC states that the standpipe must be Not less than 18" but not greater than 42" above the trap.

Does the height of the standpipe compared to the height of the washer matter? In other words, can the standpipe be lower than the top of the washer, provided it's more than 18" above the trap?

It must be above the flood level of the washer. Top of the drum for top loaders. Mine is ~39 inches from the finish floor.

 

[Sponsor]

 

[Patflemming]

Thanks for the input. I have a bit of an issue then. I plumbed a grey water system for my laundry, controlled by 2 valves. One leg empties into my 2" standpipe. The other leg is a 1" line which terminates outside in the landscape. I forgot to install a AAV/mechanical vent. I am very tight for space and dont have much room to install it directly above the downpipe because of a shelf.

Is it acceptable to install like I am showing in the picture? The vent wouldnt be directly above the downpipe but would be higher than the horizontal run. Is this allowed, or do I need to add a tee with the vent directly above?

 

[WorthFlorida]

Do you mean the to vent a drain line?

Thanks for the input. I have a bit of an issue then. I plumbed a grey water system for my laundry, controlled by 2 valves. One leg empties into my 2" standpipe. The other leg is a 1" line which terminates outside in the landscape. I forgot to install a AAV/mechanical vent. I am very tight for space and dont have much room to install it directly above the downpipe because of a shelf.

Is it acceptable to install like I am showing in the picture? The vent wouldnt be directly above the downpipe but would be higher than the horizontal run. Is this allowed, or do I need to add a tee with the vent directly above?

Is this for the washer or just want to dump water into the drain? An AAV is a one way check valve, it only allows air to enter the drain.

 

[Tuttles Revenge]

As long as the pumped hose/diverter piping rises above the flood level of the drum it can then gravity/pump into the lower stand pipe.

 

[Patflemming]

the left side that is out of frame discharges into the standpipe. That side is fine. My issue is with the new leg with the 1" pvc shown in the picture. That vertical pipe leads to outside. I forgot to add a vacuum breaker / AAV. Ideally, I would remove the elbow and add a tee with the valve above but I dont have enough space because of a shelf (you can see the brackets in the picture). I want to know if I can add a elbow on the downpipe and add the valve.

 

[Patflemming]

This might be a bit more clear, it shows all the plumbing. I need an AAV on the right side that leads to outside because it's a closed system. I just dont have much room

 

[WorthFlorida]

Is this gray water is pumped under pressure? Venting is not possible. The use of 90* elbow is for a pressurized system.

The 1" pipe going to the yard, is it for irrigation or just dump water onto the ground?

Where does this gray water come from? The washer? A shower drain?

 

[Tuttles Revenge]

If you need air relief on the discharge side of the gray water delivery pipe. I would add a similar vacuum relief for a water heater instead.

 

[John Gayewski]

Your can cut a tee in the downpipe and then 90 up to add a vacuum breaker. You might end up with the problem of the vacuum breaker dripping water from it due to the space been the added vacuum breaker and the upper piping. Without enough head this might cause the vacuum breaker to drip. This is why there's a 6 inch or minimum between the water level and the vacuum breaker.

If your add a tee and a vacuum breaker can the new pipe and vacuum breaker be in the corner to go up beside the shelf?