Question: How much slope should the main soil pipe have on a new installation? I was told by one person 1/4 inch per foot but then another person told me 1/4 inch in four feet. He told me that if there was too much slope the waste would de-water in the pipe causing clogging problems.
Which one is correct? From my furthest toilet to the stack is 20 feet and I installed it at 1/4 in per foot slope.
Thanks fro your help.
Answer: 1/4″ per foot is correct and he is right. Too much drop too quickly will allow the solids to remain in the line.