A perforated pipe underdrain is installed within a twenty-four inch wide stone-filled trench beneath a finished grade surfaced with four inches of topsoil. The trench is bedded with three inches of half-inch broken stone below the invert of the underdrain, which is sized per plan and features holes oriented upward to collect subsurface drainage. Twelve inches of half-inch broken stone surrounds the lower portion of the pipe, overlaid by gravel backfill with grading A extending up to the topsoil layer.
Members view this detail in full resolution, download the CAD files (SVG, PDF), and can adapt it in the built-in CAD editor — export DXF, DWG, or PDF.
Start membership