Retaining Wall Drainage

Old 01-30-17, 04:50 AM
Thread Starter
Join Date: May 2009
Location: USA
Posts: 228
Received 0 Votes on 0 Posts
Retaining Wall Drainage

Will installing a French drain behind a retaining wall provide a benefit?

Old 01-30-17, 05:49 AM
Join Date: May 2015
Location: USA
Posts: 3,138
Received 2 Votes on 2 Posts
It is recommended to install drainage and crushed stone backfill behind a retaining wall. You line the area with geotextile fabric [edit] lay in drainage pipe, and fill with crushed stone to 6-12 inches below surface, then wrap the fabric over and finish with soil.

The drainage prevents water from draining through the wall, taking soil with it. It's especially important in freezing climates so that damp soil behind the wall doesn't frost heave and push the wall forward.

Last edited by CarbideTipped; 01-30-17 at 07:44 AM.
Old 01-30-17, 06:06 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA - N.E.Tn
Posts: 48,163
Received 408 Votes on 364 Posts
.... and you want that drain tile to have an exit for the water it collects.
Old 01-30-17, 08:45 AM
Marq1's Avatar
Join Date: Sep 2016
Location: USA MI
Posts: 7,403
Received 505 Votes on 468 Posts
A lot depends on what you are building.

I currently have several bolder walls, from 18" up to 4' tall and did not install any drain or use any fabric without any concerns.

In an prior house I had a ravine setting and had multiple 4' high walls stacked up close to 20'. In those I installed inter connecting drain tile from top to bottom.

I'd also be more inclined to put a drain tile behind a paver stone type wall where the wall is a little more straight, if my bolder walls move a bit you would not even notice.

Thread Tools
Search this Thread
Ask a Question
Question Title: