My dad remodeled an old house for my brother before he passed away. Now they want to put a washer in the basement. The sewer line from the street comes in through the basement wall about 46 3/4" up from the floor. There is a rubber coupler from the old metal pipe to the new PVC dad ran through the house. There is a run of about 2 feet horizontally, an 90 degree elbow up, a run of about 4 foot to the floor joists and then the 90 degree to run everything else on. I'm not sure of best way to tie into the PVC for the washer drain. I have always used T's before but see there are saddles for this also. Which would be better to use? I'm leary of the pressure stress caused by the water pressure from the washing machine but a saddle would be so easy to install from the looks of it. I'm also not sure if attaching to the short horizontal run would be better or just above the 90 elbow in the vertical run. I do know I'll need a trap and add an AAV for venting plus use a PVC tubular compression adapter to connect the washer drain hose. Drawing things out, it looks like the traps would be pretty much the same height whichever place I tie into (least if I attach so new piping is above the horizontal). I'm attaching a drawing, hope it help explains things. Should I figure out some support for the plumbing since it's all just hanging in the open.

Saddle fittings are not considered a legal fitting in most states... can't use tee fittings on horizontal drain line, either (same reason).

Use a tee fitting on the vertical pipe... otherwise, all looks OK.

Hang the piping well...and make standpipe out of trap at least 18" to 24" tall.

Mark