I currently have a washing machine and dryer in the basement and wish to move them both upstairs. I can tap into the same drain line, but it will be about 20' from the old p-trap. Should I install a new p-trap upstairs and take the old one out, or can I have 2 in the same line, or is the one in the basement sufficient?
Also there is no vent in the basement for this drain line just a p-trap and about 3' of pipe sticking up; will I need a vent now that I am moving it upstairs?