To hold back the weight of soil, a wall built below grade must be strong. But even the strongest wall cannot withstand the hydraulic pressure that builds up behind it when soil becomes saturated with rainwater. So, in addition to being built solidly, the wall must have a way for water to escape. Weep holes, small in diameter and spaced 4 to 10 feet apart, allow water to come through the wall. Or, in the case of a foundation wall, you can direct water to one or both sides of a wall. The most common way to do this is with perforated drainpipe set in a bed of gravel and sloped slightly.
A landscaping retaining wall commonly is battered, that is, sloped toward the soil it retains. This gives the wall strength. Structural walls cannot be battered, so we build them strong, with plenty of reinforcement.
Types of Retaining Walls:
- Dry Stack