How To Build A Retaining Wall With Blocks

In this comprehensive guide, you will learn all the essentials of building a retaining wall using blocks. 

Whether you’re looking to enhance your landscape or solve erosion problems, this step-by-step guide will provide you with the knowledge and guidance you need to successfully complete your project, including tips for constructing a block retaining wall and when to seek professional help for a concrete block retaining wall.

Planning Your Retaining Wall

Before diving into your retaining wall project, proper planning is essential. Taking the time to design your wall carefully will ensure that it not only serves its purpose but also enhances the overall aesthetics of your landscape. 

In this section, we will guide you through the process of creating a retaining wall design that meets your needs and complements your outdoor space.

Know What Retaining Wall Design You’re Aiming For 

Retaining wall design is not just about functionality; it is also an opportunity to showcase your personal style. 

When planning your retaining wall, consider the desired height, shape, and overall layout. Also, think about the natural flow of your landscape and how the wall will fit seamlessly into the existing environment.

As you create your design, think about how the retaining wall will serve its purpose. Will it be primarily for erosion control, terracing, or creating a level area for landscaping? 

Selecting the Right Retaining Wall Materials

When it comes to retaining wall materials, there are many options. Each material has unique characteristics and advantages, such as durability, cost, and visual appeal. When selecting the right materials for your project, consider these.

Timber: Timber is a popular choice for retaining walls due to its natural appearance and affordability. It is relatively easy to work with, making it suitable for DIY projects. However, timber retaining walls may require regular maintenance and is not as long-lasting as other options.

Concrete blocks: Concrete blocks offer durability and versatility in design. They are available in various sizes, shapes, and colours, allowing you to create a customised look for your retaining wall. Concrete blocks are low maintenance and can withstand harsh weather conditions. Plus, using an interlocking retaining wall block system can simplify the assembly process and provide added stability, especially if it’s a smaller wall design.

Natural stone: Natural stone retaining walls are known for their timeless beauty and durability. They add a touch of elegance to any landscape and can be stacked or mortared together to create a solid structure. While natural stone may be a bit more expensive than other materials, it offers unmatched beauty and longevity. In construction, half blocks can be used to complete rows, create corners, and follow the manufacturer’s instructions for a precise fit.

Incorporating Your Design and Materials

Once you have finalised your retaining wall design and selected the materials, it’s time to bring everything together. Consider how your design will utilise the chosen materials to create a visually appealing and functional retaining wall.

Integrate features such as curves, steps, or terraces into your design to add visual interest and enhance accessibility. Think about how the colour and texture of the materials will complement your overall landscape design, ensuring that your retaining wall becomes an attractive focal point in your outdoor space.

Carefully planning your retaining wall design and selecting the right materials means you will be one step closer to creating a beautiful and functional addition to your landscape. 

Preparing the Site

Properly preparing the site is crucial for a successful retaining wall. Before you begin construction, follow these essential steps:

1. Clearing the area: Start by removing any vegetation, debris, or obstacles within the designated space for your retaining wall. This will ensure a clean and level work area.
2. Levelling the ground: Use a shovel or other appropriate tools to level the ground where your retaining wall will be built. It’s important to create a flat and even surface to ensure the stability of the wall.
3. Marking the boundaries: Use stakes and string to mark the boundaries of your retaining wall. This will serve as a visual guide to keep your wall on track during construction.
4. Installing landscape fabric: Lay down landscape fabric to prevent sand seepage and aid in proper drainage. Tuck the fabric behind the block during construction and use it along with gravel for effective water control.

Remember, sometimes it’s easier to enlist the help of an expert landscaper instead, especially if your property or yard layout is more complex.

Tools You Will Need

• Shovel: A reliable shovel will be essential for digging and leveling the ground.
• Tape Measure: Accurate measurements are crucial for a well-built retaining wall. Use a tape measure to ensure precision throughout the construction process.
• Level: A level will help you maintain proper alignment and ensure that your retaining wall is straight and even.
• Wheelbarrow: A wheelbarrow will come in handy for transporting materials and debris.
• Masonry Tools: Depending on the type of blocks you’re using, you may need masonry tools such as a hammer, chisel, and trowel.

With the site cleared, levelled, marked, and the landscape fabric installed, and the necessary tools at your disposal, you’re now well-prepared to begin constructing your retaining wall.

Excavation and Foundation

One of the most crucial steps in building a sturdy and long-lastingblock  retaining wall is excavation and creating a solid foundation. This process ensures the stability and durability of your wall, allowing it to withstand the test of time. 

Determining the Site and Depth

The first step in excavation is determining the location and boundaries of your block retaining wall. Take into account any slopes, water drainage, or adjacent structures that may affect the positioning of your wall. 

Once you have marked the area, it’s time to determine the appropriate depth for your foundation. This will depend on the height and material of your wall, as well as the soil conditions. 

Excavating the Site

Now that you have established the boundaries and depth, it’s time to start excavating the site. 

Begin by clearing away any vegetation or debris from the area. Use a shovel, excavator, or any suitable equipment to dig out the soil and create a trench along the marked boundaries. 

Make sure to excavate to the specified depth, accounting for additional space required for the foundation and drainage system. As you excavate, regularly check the depth and alignment to ensure accuracy.

Installing the Drainage System

A proper drainage system is essential for preventing water buildup behind your retaining wall, which can compromise its integrity. 

Once the excavation is complete, it’s time to install the necessary drainage components. This typically involves placing perforated drainpipes at the base of the wall, along with a layer of gravel to facilitate water flow. 

The drainpipes should extend away from the wall and connect to a suitable drainage outlet, ensuring efficient water dispersion. This system helps the wall withstand immense pressure from the soil.

Compact and Level the Soil

After installing the drainage system, it’s important to compact and level the soil within the excavated area. This ensures a stable base for your retaining wall and helps distribute the weight evenly. 

Use a compactor or tamper to compact the soil, making sure it is firm and well-settled. Additionally, use a level to ensure the surface is perfectly flat and aligns with the designated height for your foundation. Take your time during this step to achieve optimal results.

Installing the First Course

When it comes to retaining wall construction, building a strong foundation is of utmost importance. The first course of blocks sets the stage for the rest of the wall, ensuring its stability and longevity. In this step-by-step retaining wall guide, you’ll learn how to properly install the first course of blocks and create a solid base for your project.

To ensure level and aligned blocks, follow these simple steps:

1. Prepare the ground: Clear the area where your retaining wall will be placed, ensuring it is free of any debris or vegetation. Level the ground using a shovel or grading rake, removing any high spots or loose soil.
2. Mark the layout: Before placing the first course of blocks, mark the layout of your wall using stakes and string. Make sure to outline the boundaries accurately, following any curves or angles in your design. This will help guide you during the installation process.
3. Start at the lowest point: Begin building the first course of blocks at the lowest point of your wall. This will allow you to work your way up more easily and ensure proper drainage. Use a tape measure, level, and string to ensure each block is placed at the correct height and aligned with the layout.
4. Backfill and compact: As you install each block, backfill behind it with gravel or crushed stone, ensuring there are no voids. This will provide additional support and drainage for your retaining wall. Use a tamp or plate compactor to lightly compact the backfill, creating a solid base.

Building Additional Courses

Now that you have successfully installed the first course of blocks for your retaining wall, it’s time to move on to building the additional courses. This step is crucial for achieving the desired height, alignment, and stability of your wall. Follow this guide to ensure a seamless construction process.

Stacking the Blocks Layer by Layer

When building the additional courses, it’s important to stack the blocks layer by layer, ensuring a secure and structurally sound wall. DIY segmental retaining walls can be easily constructed using these methods. Here’s a step-by-step process to help guide you:

1. Prepare the work area: Clear any debris or loose soil from the construction area. Ensure that the base is level and compacted.
2. Apply adhesive: Place a bead of construction adhesive on the top of the previous course of blocks to create a strong bond.
3. Position the block: Carefully place the block on top of the adhesive, making sure it is aligned and level with the previous course.
4. Continue the process: Repeat steps 2 and 3 for each block, ensuring that they are tightly stacked together.
5. Check alignment: Use a level to verify that each course is properly aligned both horizontally and vertically.
6. Adjust if necessary: If any blocks are out of alignment, gently adjust them to ensure a straight and level wall.

Reinforcing and Connecting the Blocks

To enhance the stability and strength of your retaining wall, reinforce and connect the blocks securely. Here are some techniques you can try:

• Install a geogrid: A geogrid is a reinforcement material that helps distribute the load across the wall. Follow the manufacturer’s instructions for proper installation.
• Create interlocking connections: Some block systems have built-in features that allow for interlocking connections. Use these to enhance the stability of your wall.
• Use adhesive: Apply construction adhesive between the blocks in each course to create a strong bond and prevent shifting.

Finishing Touches and Maintenance

Now that you have completed the main structure of your retaining wall, it’s time to add the finishing touches that will enhance its visual appeal. Various options are available for adding caps or finishing blocks to give your wall a polished look.

Retaining wall construction and building a block wall requires attention to detail, even in the final stages.

You can opt for capstones that sit on top of the blocks, providing a clean and cohesive finish. These caps come in different shapes, sizes, and colours, allowing you to select the one that complements your landscape design.

Alternatively, you can choose to incorporate finishing blocks into your retaining wall design. These blocks have decorative patterns or textured surfaces, adding a visually appealing element to the overall structure. Planter boxes can also be incorporated into the retaining wall design for added functionality.

In addition to the aesthetic aspects, it is essential to prioritise maintenance to ensure the longevity of your retaining wall. Regular inspection and proper care will help prevent any potential issues in the future.

Inspect your retaining wall regularly for any signs of damage, such as cracks, shifts, or bulges. If you notice any issues, it’s important to address them promptly to prevent further damage.

To maintain the stability and effectiveness of your retaining wall, make sure to clear any debris, dirt, or vegetation that accumulates behind the wall. This will help prevent water buildup or pressure that can weaken the structure over time.

Additionally, check the drainage system of your retaining wall. Ensure that it is properly functioning and not clogged. A well-maintained drainage system will prevent water from 

Key Takeaways:

• Building a retaining wall with blocks can improve the functionality and aesthetics of your landscape.
• Proper planning and design are crucial for a successful retaining wall project.
• Preparing the site and creating a solid foundation are essential steps in the construction process.
• Installing the first course and building additional courses require careful alignment and proper reinforcement.
• Finishing touches and regular maintenance will ensure the longevity of your retaining wall.

FAQ

What materials do I need to build a retaining wall with blocks?

To build a retaining wall with blocks, you will need the following materials: retaining wall blocks, gravel, sand, geogrid (if necessary), construction adhesive, and drainage pipe.

Do I need a permit to build a retaining wall?

The need for a permit will depend on the height and location of your retaining wall. It’s important to check with your local council or building department to determine if a permit is required for your specific project.

How deep should the foundation of a retaining wall be?

The depth of the foundation will vary depending on the height and soil conditions of your site. As a general guideline, the foundation for a retaining wall should be at least one-third of the wall’s height.

Can I build a retaining wall on a slope?

Yes, it is possible to build a retaining wall on a slope. However, additional engineering and design considerations may be necessary to ensure the stability of the wall. It’s recommended to consult with a professional if you are planning to build a retaining wall on a slope.

How do I ensure proper drainage behind the retaining wall?

Proper drainage is crucial for the long-term stability of a retaining wall. To ensure proper drainage, you can incorporate a perforated drainage pipe behind the wall and use gravel or crushed stone as backfill material. This will allow water to drain away from the wall and prevent hydrostatic pressure build-up.

Can I use retaining wall blocks for other landscaping projects?

Retaining wall blocks can be versatile and used for various landscaping projects. They can be used to create garden beds, terraced areas, seating walls, or even outdoor kitchens. The durability and aesthetic appeal of retaining wall blocks make them a popular choice for many landscaping applications.

How long does it take to build a retaining wall with blocks?

The time it takes to build a retaining wall with blocks will depend on various factors, such as the size and complexity of the project, the experience of the builder, and the availability of resources. While smaller projects can be completed in a few days, larger or more intricate walls may take several weeks to finish.

Do I need to hire a professional for building a retaining wall with blocks?

Building a retaining wall with blocks can be a DIY project for those with some construction experience. However, for larger walls or more complex designs, it may be beneficial to hire a professional contractor who specialises in retaining wall construction, like Trinity Landscape & Sports. We can ensure proper engineering, design, and construction techniques for a long-lasting and structurally sound wall.