Spring is the time of the year to watch out for leaning, shifting, and buckling retaining walls. This happens because of either poor base preparation, inadequate building material, or improper drainage behind the wall.
When constructing a retaining wall of any size the base material is one of the most important aspects of the entire wall. If the foundation fails everything else will follow. The base needs to be a crushed rock material that will compact and drain well. There also needs to be a large enough platform to support the wall that is being built. This varies on every wall but over-building is never a bad idea. As a rule, a minimum of six inches of crushed material should be used and at least half of the first row of building material should be buried below grade.
The constructions material being used is also important. Whatever the material, it needs to be suited for the application. A smaller wall block will not suffice for a larger wall that is holding back a large slope or a patio. Be sure to speak with the manufacturer to determine which unit is suitable for your project. Again, over construction os never a bad idea.
The third factor, that causes walls to fail, is drainage. This is probably the most overlooked, as well, since it doesn’t directly affect construction but water may be the number one reason for retaining wall failure. It is important to deflect as much water as possible away from the wall by way of grading and redirecting downspouts to other areas. There should also be a drain stone behind the wall, as well as a drain pipe at the bottom to carry any water that collects away from the wall.
If you have a retaining wall in need of repair or are looking to build one follow these steps. Of course, you can always contact BladeRunners Landscaping, Inc. for advice or help on your project or visit our website at bladerunnerslandscape.com to view photos. When these factors are addressed a retaining wall will last and stay beautiful for years to come.