Retaining Walls

There are four main concepts in retaining wall design

Base – Your retaining wall must be built on a stable base. The base of a retaining wall should be set at ground level. The taller a wall is, the further below ground level it should be set.

Backfill – Backfill refers to the dirt behind the wall. In order to provide proper drainage, at least 12 inches of gravel or a similar material should be installed directly behind the wall. For landscaping behind the wall, 6 inches or more of native soil should be placed over the backfill.

Drainage – Proper drainage is crucial for retaining walls. There are a few ways to ensure that effective drainage is taking place, including backfilling at least a foot of space behind the wall with gravel, have a perforated pipe installed along the inside, or backfilled, bottom of the wall, or weep holes, which allow water to drain through the wall.

Height – The height of a retaining wall determines how much weight it can hold and how much extra reinforcement might be necessary. Typical residential retaining walls are constructed between 3 and 4 feet high, a height that provides excellent strength without requiring additional reinforcements. If your yard requires a higher wall, your landscape designer may suggest a series of 3-4 foot walls to create a terraced effect.