Retaining Wall French Drain Detail

The purpose is to take water from wet areas and disperse it into dry areas.

Retaining wall french drain detail.

1 2 m in height or with slopes or other surcharges above the wall will need a toe drain. Otherwise water moving down the hill will build up behind the wall and undermine it. The process of making sure that a retaining wall drains properly is relatively simple but it is not very flexible. If aggregate of different sizes is used smaller pieces usually go closer to the pipe while larger pieces sit closer to and on the.

If you re building a retaining wall add a french drain behind the first course of stones or blocks. 300 mm behind the block. Although there are exceptions most retaining walls require gravel backfill soil compaction pipe or toe drains and weep holes. Block setback options large batter pdf dwg.

We re gonna show you how to build a retaining wall that won t fall over. Gravity walls solid 41 inch 1030mm hollow core and xl blocks all gravity wall details pdf. The size of the gravel used can vary from pea gravel to larger pieces of river rock. About 8 inches to 2 feet deep should be sufficient for many water diverting projects though related systems such as those built around foundations and sub ground living spaces as well as the bases of retaining walls may be deeper.

The pipe should rest on the same compacted gravel base or concrete footing that supports the wall. 41 inch hollow core section pdf dwg. Solid block wall section pdf dwg. It s not crazy.

The loose gravel and perforated tubing help facilitate that water movement. Check out this video for some simple instructions on installing a french drain behind an 18 to 24 tall retaining wall before it is backfilled with dirt. Alternating planter 5 degree batter wall section pdf dwg. For a stacked block retaining wall that s no higher than four feet a trench filled with three inches of crushed rock will help keep the wall from shifting and settling.

The exact depth of the. Xl wall section pdf dwg. Large batter wall section pdf dwg. A french drain is a trench dug in the ground into which a perforated tube is placed and which is then filled with gravel or lose rocks.

Today we re rebuilding a retaining wall that wasn t built correctly. The toe drain and the wall rock is designed to remove incidental water from behind the wall and is not meant as primary drainage path for above or below grade water management. Together these four features will provide adequate drainage for most designs.