Posted 4/25/2015 20:33 (#4537781 - in reply to #4537301) Subject: RE: More on pattern tiling
Depends on soil structure. Usually 4" on 50' centers. On tighter soils will go down to 4" on 40' and did one low sot 4"on 25'. When possible prefer 30"cover on top of the tile but have gone as shallow as 24" of cover. Have tore out too much old tile to go any shallower. Go too deep & it drains the soil too slow.
More on pattern tiling
