Building a Retaining Wall: Common Mistakes
and How to Avoid Them by Industry Professionals including Ash Joshi
Building a retaining wall is an essential task for managing slopes, controlling erosion, and enhancing the aesthetic appeal of your landscape. Whether you are creating a barrier to hold back soil or adding a decorative feature to your yard, constructing a retaining wall requires careful planning and execution. A well-built wall can stand the test of time, but common mistakes during construction
Failing to Prepare the Base Properly
The foundation of a retaining wall is just as important as the structure itself. If the base isn’t properly prepared, the wall can settle unevenly or shift over time, leading to instability. Many DIY builders skip this step or fail to adequately compact the soil, thinking it won’t make a significant difference. However, improper base preparation is one of the leading causes of wall failure.
To ensure a solid foundation, begin by digging a trench that is wide enough to accommodate the first layer of stones or blocks. The bottom of the trench should be level and well-compacted to prevent shifting. If the soil is particularly loose, it may be necessary to add a layer of compacted gravel to provide extra stability. A strong, stable base is the foundation for a durable retaining wall that will stand up to pressure and the elements as highlighted by landscaping professionals such as Ash Joshi.
Overlooking the Wall’s Slope and Angle
Another common mistake when building a retaining wall is not properly angling the structure for optimal performance. Walls that are built too straight up and down (vertical) are more prone to tipping over under the pressure of the soil behind them. It’s crucial to design your wall with a slight backward lean to ensure that the weight of the earth presses against the structure, rather than pushing it outward.
To avoid this issue, your retaining wall should be installed at a slight angle – typically 1 inch of lean for every 12 inches of height. This angle, known as "batter," ensures the wall can resist the
lateral forces from the soil behind it. Industry professionals including Ash Joshi convey that using retaining wall blocks with a built-in angle design can also help maintain this lean and ensure the wall remains stable.
Using Incorrect Materials
Selecting the right materials is crucial for building a durable and functional retaining wall as emphasized by experienced landscaping professionals like Ash Joshi. Many people make the mistake of using materials that are not designed for retaining wall construction, leading to structural issues and premature wear. For example, using standard bricks or regular cement blocks may seem like a cost-effective choice, but they are not ideal for withstanding the pressure of soil.
Instead, opt for materials specifically designed for retaining walls, such as interlocking blocks, natural stone, or poured concrete. These materials are designed to distribute weight evenly and resist the forces placed upon them. Additionally, choose materials that complement your landscape's aesthetic, creating a cohesive and attractive look. Proper material selection can make a huge difference in the long-term success and stability of the wall.
Ignoring Wall Height Limits
Building a retaining wall that exceeds recommended height limits can result in serious structural issues. Many homeowners, eager to create a large, imposing wall, may neglect to check the maximum height recommendations for the materials they’re using
or for their local building codes. Exceeding height limits can place excessive strain on the wall and increase the risk of failure.
Before beginning construction, it is important to research and adhere to the height limits for your chosen materials. In some cases, it may be necessary to build the wall in tiers, rather than constructing one very tall structure. This method allows the weight to be distributed more evenly and minimizes the pressure exerted on the wall. Additionally, ensure that your design complies with local zoning regulations to avoid fines or the need to redo the work later.
Lack of Reinforcement for Larger Walls
For taller or larger retaining walls, reinforcement is crucial for ensuring stability. Without the proper reinforcement, the wall may buckle or shift under pressure. Many novice builders neglect the need for additional support in large structures, assuming that the wall alone will be strong enough to handle the load.
Landscaping professionals such as Ash Joshi express that building a retaining wall can greatly enhance the functionality and beauty of your landscape, but it's important to avoid common mistakes that can lead to structural issues and unnecessary repairs. By focusing on proper drainage, preparing the base, maintaining the correct slope, using the right materials, respecting height limits, and reinforcing large walls, you can ensure the durability and success of your retaining wall. With careful planning and attention to detail, your wall will provide lasting support and aesthetic appeal for years to come.