What size rock for french drains?
Rock for drainage is used in both construction and landscaping from septic systems to French drains. This rock is generally a round rock that is dredged as opposed to mined. The most common drainage rock, or perhaps the most versatile in my experience, is 1-1/2". This size provides a large enough gap that liquids can easily pass through and even some minor solids and mud can get through and keep the drain functioning.
Of course, the larger the rock the larger the draining ability, but most common seems to be 1-1/2".
What size rock is used for french drains most in your neck of the woods?
Filed under Filling the Bins by bruce
Comments on What size rock for french drains? »
M. D. Vaden - Portland Landscape & Trees @ 6:22 pm
My favorite size is pea gravel.
Water can gush right into it Smaller openings, but more of them.
The big benefit with pea gravel, at least in Portland landscaping, is that it prevents a lot of barkdust and leaves and other particles from dropping down inside and beginning to fill the cavity around the pipe. And in the long run can extend the lifespan of the French drain. This is pretty much pertaining to ADS perforated drain pipe.
MDV / Oregon