I would like to move my washer and dryer from one side of the basement to another. However, for me to run a drain line from my slop sink to the current drain pipe, it needs to run apx 60 feet along an outside wall. There is no direct route to the drain, unless I run it through the rafters. I am using 1-1/2" PVC pipe for the drain.
My questions are as follows - what is the minimum slope I would need to allow for the drain to properly flow? Is there an inexpensive alternative to a grinder pump to increase the flow? Any help is greatly appreciated.