Building Code

• Before you begin building a retaining wall, you need to obtain a permit from your local building department. Building codes tell you exactly how to build the wall to meet minimum requirements. These specifications are designed specifically with safety in mind. Building codes explain where the retaining wall is allowed, how high it can be, the drainage required, backfilling requirements and other structural specifics of the retaining wall.
  
  

Ground Preparation

• Since a retaining wall requires digging, first have utility lines in your yard marked. The One Call system is used to have those items marked. Call 811 anywhere in the country to be routed to the local branch that handles this marking. Plan the retaining wall around the utility lines. A level base for the retaining wall is essential for a straight, stable structure. Use a level to ensure the ground under the wall is level and straight along the distance. Dig out additional dirt or use a tamper to help level out the area.
  
  

Size

• Smaller and shorter retaining walls generally are easier to build and safer than long, tall walls. A large wall needs large, heavy retaining wall bricks for better stability and safety. Larger retaining walls also require a geogrid or a soil retention mat, which helps reinforce the soil behind it. For the safest retaining wall structures, keep the walls as short as possible. If you're building the structure on a tall slope, break up the hill into two or more terraces with a short retaining wall creating each terrace. This creates a gradual step-down and allows you to keep the structures shorter for a safe design.
  
  

Construction

• You will find various types of retaining walls -- some that hook together with pins and others that lock into one another with a back lip and the force of the dirt behind the bricks. The retaining wall should lean back toward the hill as it gets higher for more strength. Retaining walls typically are backfilled with crushed gravel to provide drainage and support for the wall. The gravel needs to be compacted with a tamper for the greatest stability and safety.