What is the minimium slope for each one foot of length of a buried soil pipe? The soil pipe is 175 feet from the toilet to the sewer pit.

For 3" pipe it is 1/4" per foot. For 4" pipe it is 1/8" per foot.

Therefore, in your case, it will be: about 44" of overall slope for 3" pipe and 22" of slope for 4" pipe. Plus, you have to add the depth of your toilet 90. You measure from top of that 90 forward...

The proper slope for drain and waste piping is 1/4" per foot. At this rate the water has sufficient scouring capability to help keep the drain lines clear. Piping 4" and above can be sloped at 1/8" if you don't have sufficient depth to run 1/4". Avoid putting too much slope on the piping if you have a lot of turns as the water will tend to run away from solids, Thanks.

John

Hey Frank,

you have to add the depth of your toilet 90. You measure from top of that 90 forward...
We figure the fall of our sewer pipe from the foundation clean out to the sewers terminal and not from any fixture in the house. That slope's already been determined by the rough in plumber. But the answers are correct about fall. 1/4" per foot for 3" and under and 1/8" for an 4" sewer line. Good luck, Tom

Tom, he doesn't specify whether he is installing new fixture or replacing existing sewer starting at the foundation. I added that detail for that reason. Ohterwise, some people don't take the depth of toilet 90 into consideration...

A sewer line has a fall of 1.5 feet. If the pipe slope is 0.28%, what is the length of the sewer in feet

Hello Jaclark, few things first:

1. You are attaching your question to 3 1/2 year old thread. If you want to ask a question, start your own thread
2. Your question is missing on more piece of information: size of sewer pipe
3. This is not an apprentice school. If you have a plumbing problem or need help with on-going plumbing situation, you post your problem in detail and one of our Experts will help you.

Besides: why are you asking ?

Back to you. Milo

A sewer line has a fall of 1.5 feet. If the pipe slope is 0.28%,
Say what??