Installation
Drainage Pebbles: Selection and Installation
Two things make a drain last: the right grade, and a geotextile between stone and soil.
Buy Pebbles editorial team · Reviewed by the Buy Pebbles supply desk · Published · 5 min read
Choosing the grade
20–40 mm is the standard band for French drains. Finer material silts up; coarser material leaves voids large enough for soil to migrate into even through a membrane.
Separation is not optional
Line the trench with geotextile, place the stone and pipe, then fold the fabric over the top before backfilling. Drains built without this fail quietly over a few seasons.
Planters and terraces
A 50–75 mm drainage layer under planter soil, separated by fabric, prevents waterlogging. On terraces, coordinate with the waterproofing detail and keep outlets accessible.