How to Build a Retaining Wall: A Step-by-Step Guide

How to Build a Retaining Wall: A Step-by-Step Guide

Table of Contents

Retaining walls fulfill two important purposes in landscape design: they are both practical and visually appealing. These structures are essential for controlling sloping areas, stopping soil erosion, and establishing level areas in places where the ground is uneven. Although the thought of constructing a retaining wall on an inclined surface might initially appear challenging, with the right direction and understanding of the procedure, you can successfully build a retaining wall that is both attractive and sturdy on your own!\u00a0

In this step-by-step guide, we’ll walk through everything from design and materials selection to construction, drainage, and drainage of the finished project.

Before beginning a retaining wall project, it’s vitally important that you understand its basic concepts: its purpose and what elements make up a successful installation. Having this knowledge will form the basis of its success and serve as an essential starting point.

What Is a Retaining Wall?

A retaining wall is a structure designed to retain soil on sloped terrain, leveling out changes in elevation or preventing erosion while increasing visual appeal on properties. Building such a retaining wall requires careful planning in order to ensure stability and longevity.

The Importance of Proper Wall Design

Effective retaining wall design is crucial to the success of your project. A well-designed wall not only serves its functional purpose but also adds to the aesthetic value of your landscape. Here are some key design considerations:

Wall Height

The height of your retaining wall will influence the design and construction method. Taller walls may require additional structural support and engineering.

Soil Pressure

Understanding the type of soil and its pressure on the wall is essential for selecting appropriate materials and design features.


Proper drainage is vital to prevent water buildup behind the wall, which can cause structural issues. Incorporating drainage elements into your design is a critical step.

Wall Blocks

Selecting the right retaining wall blocks is a key decision. They come in various styles, sizes, and materials, and your choice will impact the wall’s appearance and stability.

Now, let’s dive into the step-by-step process of building a retaining wall on a slope.

Step 1: Plan Your Retaining Wall

Assess Your Landscape

Before you start digging or purchasing materials, assess your landscape. Consider the following factors:

  • Slope Angle: Determine the steepness of the slope where you intend to build the retaining wall.
  • Soil Type: Identify the type of soil you’re working with, as this will impact drainage and wall design.
  • Drainage Issues: Check for existing drainage issues and plan how your retaining wall will address them.

Obtain Necessary Permits

Depending on your location and the height of your retaining wall, you may need permits or approvals. Contact your local building department to ensure compliance with regulations.

Step 2: Choose Your Materials

Select Retaining Wall Blocks

Choose the type of retaining wall blocks that suit your design and structural requirements. Consider factors like block size, shape, color, and texture.

Gather Other Components

You’ll need additional materials such as wall caps, construction adhesive, landscape fabric, and drainage components. Ensure that you have all the necessary items before beginning construction.

Step 3: Prepare the Site

Mark the Layout

Mark the layout of your retaining wall using stakes and string lines. This will guide you in creating a straight and level wall.

Excavate the Area

Dig a trench for your wall’s base. The depth and width will depend on your wall’s height and the size of the retaining wall blocks.

Create a Solid Base

Build a stable base for your retaining wall using crushed gravel or crushed rock. Compact this base material with a hand tamper or a mechanical compactor.

Step 4: Build the Retaining Wall

Lay the First Course

Begin by laying the first row of retaining wall blocks on top of the prepared base. Ensure they are level and properly aligned.

Add Drainage

As you build the wall, incorporate drainage elements, such as a perforated pipe, behind the first course of blocks. This will help channel water away from the wall.

Continue with Additional Courses

Continue stacking blocks to build subsequent courses. Use a level and rubber mallet to ensure each block is perfectly level and secure. Stagger the joints of adjacent blocks for stability.

Step 5: Finish the Wall

Cap the Wall

Install wall caps to finish the top of your retaining wall. Wall caps provide a polished look and help protect the wall from the elements.

Backfill the Wall

Fill the space behind the wall with a layer of gravel or crushed rock. This assists in drainage and prevents soil pressure from building up.

Step 6: Ensure Proper Drainage

Landscape Fabric

Place landscape fabric between the backfilled soil and the wall to prevent soil from seeping into the drainage materials.

Proper Drainage

Ensure that any water that collects behind the wall can drain properly. This may involve adding drainage pipes or channels.

Step 7: Consider Professional Guidance

Consult a Structural Engineer

For taller walls or projects with complex requirements, it’s advisable to consult a structural engineer. They can provide expert guidance on the design and stability of your retaining wall.

Engage a Landscape Architect

For landscaping projects that demand a high level of design sophistication, a landscape architect can help you create a visually stunning retaining wall that integrates seamlessly with your landscape.

Get Expert Guidance on Your Retaining Wall Project in Tacoma!

Building a retaining wall on a slope is a rewarding DIY project that can enhance the functionality and appearance of your property. By following the step-by-step guide provided here, you can create a stable, attractive, and long-lasting retaining wall that effectively manages elevation changes, prevents erosion, and adds value to your landscape. 

Remember to plan carefully, choose the right materials, and prioritize proper drainage to ensure the success of your retaining wall project. Whether you’re building shorter walls for a small garden or tackling a taller project, this guide has you covered from start to finish. For professional assistance and guidance, contact SMB Retaining Walls in Tacoma, WA, at 253-544-3066.


Can I build retaining walls taller than a few feet on my own?

While DIY projects are possible for shorter walls, constructing retaining walls taller than a few feet may require professional assistance. Consult a hardscape professional for guidance.

How do I build a retaining wall on a steep slope?

Building a retaining wall on a steep slope follows similar steps, but it’s essential to address proper drainage and use appropriate materials to manage the additional soil pressure. 

What materials can I use for my new retaining wall?

You can use various materials, including concrete blocks, natural stone, or wood. The choice depends on your design preferences, project requirements, and budget.

Should I be concerned about underground utility lines when building a retaining wall?

Yes, it’s crucial to check for the presence of underground utility lines before excavation. Contact your local utility company to mark any lines, ensuring safety and compliance.

Can I build retaining walls with concrete blocks in a straight-wall design?

Yes, concrete blocks are commonly used in retaining walls. They are versatile and available in various styles, including for straight walls. Proper construction is key to their stability.