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What size stone should be used over the 4″ perimeter drain line?

russdrollinger | Posted in General Questions on

What size stone would you recommend using over the 4″ perimeter drain line?

Thank you

Russell Drollinger

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  1. Expert Member

    That's a question most builders have never asked themselves. You simply call the quarry or your excavator and ask for drain rock.
    I guess the lower limit is determined by the size of the holes in the perforated PVC, so nothing smaller than 3/4". Too large and it can shatter the pipe when placed.

  2. wjrobinson | | #2

    Drainage stone does not have fines. We use many sizes depending on the use and more.
    The stone should be all one size such as
    3" cobble
    4-6" for surface ditch lining that is not driven on.

    We just did a french drain with filter fabric 3" around schedule 30 drilled pipe, topped with crushed #2 which is 1s 1As 2s no dust (no fines). The top is driven on.

  3. GBA Editor
    Martin Holladay | | #3

    I like 3/4 inch stone because it is easier to shovel and rake than larger stone. Of course, no fines.

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