Hello - I'm a little confused about the 1/8-1/4" per foot slope rule for waste pipes. My understanding is that the UPC rule for waste pipes carrying solids is generally 1/4"/ft minimum (or vertical). What about pipes from showers, sinks, or clothes washers? Can they slope after the vent at more than 1/4"/ft, say 45 degrees or any angle up to vertical? This is probably a dumb question but I haven't found a clear explanation.