If you have a sloping or uneven landscape, building a retaining wall can help to stabilize the soil. The wall helps to consolidate the ground and prevent erosion through the redistribution of lateral pressure caused by the slope. Concrete, bricks, wood, stone or railroad ties are some of the materials commonly used to build the wall. For greater erosion control, you can opt for a stair-like design. Different materials or plants can be placed on each separate level for a more attractive appearance. A well built retaining wall helps to enhance your landscape considerably. You want to make certain that you avoid some common mistakes as you construct your wall.
For safety considerations, it is best not to construct a wall that exceeds a height of 6 feet. Walls that exceed this height are unlikely to remain stable. Higher walls require additional structural support such as vertical support posts or guard rails. The higher the wall, the more likely it is that it will lean and collapse in the near future.
It is vital that you strive to ensure a level surface for your wall from side to side. This contributes to the resilience and long-term stability of the wall. Levelness must be upheld from the moment you excavate. Be sure to make the bottom of the trench as level as possible. A tamper and level can help you create an even and solid surface. Compact the soil thoroughly, so that you have a level foundation. This makes it easier to line up your blocks or other material used in construction.
Failure to Backfill Each Layer
When you backfill each layer, it gives the wall substance. It also creates a downward drainage path which enhances proper drainage. The backfill gives the wall higher resilience, as it draws support from the slope to hold the wall in place. Suitable materials to be used as backfill are pea gravel, sand or leftover soil.
Do not build your wall to be perfectly vertical. It is best to set each layer back by about ½ an inch. This creates a wall that is slightly inclined towards the back. A back-leaning wall has a higher capacity to counter the pressure of the earth behind it. This adds to the durability of the wall. A perfectly vertical wall is more likely to succumb to the pressure of the earth behind it, and will disintegrate in a shorter period.
It is easy to overlook drainage when building a retaining wall. Proper drainage ensures that water does not accumulate behind the wall. Accumulated water tends to freeze during cold weather. This causes the soil to expand and misalign the top of the wall. Higher lateral pressure tends to weaken the wall which eventually collapses. To counter this, create a drainage path for the water when you build the bottom layer of the wall. Leave some small spaces in between the construction material, to allow the water to flow from behind the wall. You could also install a perforated pipe at the base of the wall. Cover the pipe with small stones or gravel so that it doesn’t get clogged. Thereafter, you can add soil and compact it.