Add washing machine drain

[jmorten]

I would like to add a washing machine drain to our laundry area. Currently, the drain goes into the sink but I am looking for a cleaner method.

Looking at the picture, the sink drains into the largest pipe and has a vent that is the left verticle pipe. The middle verticle pipe goes into the ground. The right verticle pipe has the sink drain into it along with a bathroom and kitchen from upstairs.

Is there a way I can tap into one of these pipes to add a drain? I'm hoping I can add it to the middle verticle pipe.

 

[wood4d]

You can drain a washer into a sink with an 1 1/2 drain but for a washer box you need a 2" pipe. The reason why is because the sink will hold inches of water which would overwhelm a 1 1/2 pipe. To do this you would need to tap into the 3" line with a 3x2 ty instead of the 3x1 1/2 fitting that you have.