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Anyone have any experience with an acceptable slope for a 60 ft 4 inch abs run?
I have an eight foot vertical drop and a 1/4 inch per foot natural drop over the sixty feet to the existing septic
interested in code and practical experience slopes (Ill never make the inch per foot - too much digging in blue rock)
thanks in advance
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I'm almost positive min. drop is 1/4, not 1 inch. That's what it is at my house, plumbed to code.
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Thanks for the heads up - the 1 in 12 rule comes up a lot. I did do some home work and indeed 1/4" a foot seems to be the abs standard slope.
1" in 12" is roofing ...... or was that coast guard minimum scarf angle - I hate getting old.
thx
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1/8" is minimum, 1/4" is preferred. 3" often works as well as 4"
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One inch drop would make liquids over run solids, is almost as bad as not enough drop.
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I had a septic repair where a new 20' run was put in with less than 3" drop over the whole run - passed all inspections, didn't give trouble the year before we sold.
The problem we had there was when groundwater rose above the drainfield level, shower drains were less than 6" above outside ground level - previous owners had brought in fill over the whole back yard - too much fill. Still, it was only a problem during sustained torrential rains of 3 days or more.
