*
Ron, We install drainfields as a part of our business so here are my thoughts….Yes, you should slope the pipe 1/4″ per foot going into the tank. Put your tank as close as possible to the house (usually about 10′) The pipe will not freeze at any depth if your tank is working properly and it is not too far from the house. If you must go some distance, insulate around the pipe with styrofoam. Put a slight slope to your drainfield. Be sure it is a closed (boxed in) system with all pipes interconnected. Use a distibution box to meter out liquids equally to the individual runs. I prefer a bed of 1 1/2″ washed stone about 6″ deep under the drain pipes. This is easy for us to grade with a bulldozer. Then we lay out and assemble the pipes working away from the box and filling over the pipes with stone as we back away. Finally, we cover the field with landscape cloth and then backfill. Remember that your system will not last long if you don’t maintain your septic tank! Also watch what you run into it. Bleaches, fats and water softener flush water are very hard on these systems. Good luck !
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Framing the floor inside a crawlspace foundation keeps a gable-end addition close to grade.
Featured Video
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Fine Homebuilding Magazine
Fine Home Building
Follow
-
Fine Homebuilding
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial Now -
GBA Prime
Get instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
*
Ron, We install drainfields as a part of our business so here are my thoughts....Yes, you should slope the pipe 1/4" per foot going into the tank. Put your tank as close as possible to the house (usually about 10') The pipe will not freeze at any depth if your tank is working properly and it is not too far from the house. If you must go some distance, insulate around the pipe with styrofoam. Put a slight slope to your drainfield. Be sure it is a closed (boxed in) system with all pipes interconnected. Use a distibution box to meter out liquids equally to the individual runs. I prefer a bed of 1 1/2" washed stone about 6" deep under the drain pipes. This is easy for us to grade with a bulldozer. Then we lay out and assemble the pipes working away from the box and filling over the pipes with stone as we back away. Finally, we cover the field with landscape cloth and then backfill. Remember that your system will not last long if you don't maintain your septic tank! Also watch what you run into it. Bleaches, fats and water softener flush water are very hard on these systems. Good luck !
*
Here in Michigan, I have to construct a sand mound drain field for my new house. I am trying to determine how high the top of my foundation needs to be and I have several ?'s: 1. Should the waste pipe exiting the foundation slope @ a 1/4" per foot to the tank? 2. What is the minimum distance below grade that the pipe should exit the foundation to prevent freezing?
3. What slope should the drain field tiles have? ( I heard conflicting opinions of no slope, 1" per 50', and 3" per 50'). 4. Finally, Are there any tricks to keeping the drain tiles in place and at the appropriate elevation while covering them with stone? Thanks