The Different Types of Retaining Walls
When constructing any property or structure, walls are perhaps the most important element.
They support roofs, floors and ceilings and help to enclose a space to ensure the building is provided with the necessary shelter and security. Often, walls are also used to contain utilities like wiring and plumbing.
If you’re building on uneven terrain or an area that is at risk of potential soil erosion, retaining walls are often the solution that people turn to. Not only are they functional, but in many cases they can enhance the aesthetic appeal of the structure and surrounding landscapes.

What Is A Retaining Wall?
A retaining wall is a wall that is used to hold back water or earth on one side of it. Built above ground, they tend to be vertical, or as vertical as possible, which are designed in an innovative way that creates a level area on a site that may be naturally sloped.
They can also be used to prevent soil from moving or eroding away. As well as level surfaces, they are often used to help manage the runoff from water and keep landscapes stabilised. You will commonly see retaining walls in gardens, roadways and construction sites where it is essential to keep soil as stable as possible.
In addition to their structural purpose, retaining walls can also significantly enhance the visual appeal of certain outdoor spaces. They can be constructed from various materials such as concrete, stone, wood or steel which allows for customisation based on the individual requirements of the project.
The way in which retaining walls are designed means that soil can be restrained and maintained at an angle that is steeper than the material’s repose angle – or the angle that it can naturally hold without failing. In order to achieve this, the wall needs to be able to withstand the natural lateral pressure of the earth. The greatest amount of pressure is therefore exerted at the base of the wall as the deeper the backfill the higher the amount of vertical stress. This is what allows the wall to hold back the soil without collapsing or compromising the structural integrity of the building.
Types Of Retaining Walls
There is a wide range of retaining walls and they come in a whole host of shapes and sizes.
The type that is most appropriate for your project will depend on your specific requirements but the main four retaining walls that are most commonly used include:
- Gravity retaining walls
- Cantilever retaining walls
- Anchored retaining walls
- Sheet pile retaining walls
Let’s take a closer look at the different properties of these walls.
Gravity Retaining Walls
As the name suggests, gravity retaining walls use the natural gravitational pull of their own weight to resist the lateral earth pressure from the soil behind them.
It is this force that stops the structure from falling or collapsing, and this type of retaining wall is the simplest to install.
Dating back thousands of years, retaining wall structures can be seen as far back as ancient Egypt. They are constructed using concrete, masonry and bricks and they rely on the strength of their own weight to ressit toppling or sliding.
They are typically designed to be wider at the base and feature sloped sides that help them to easily resist the lateral earth pressures that are impacting them. Fairly straightforward to build, they are suitable for heights of up to 3m.
If a property is higher than 3m, gravity retaining walls cannot be used. This is because they will become too heavy and susceptible to collapse.
Cantilever Retaining Walls
Cantilever walls are built using reinforced concrete and are shaped like an inverted T or an L.
They are built using a stem and a base which is positioned under the backfill. Then, any vertical stress behind the wall will be transferred directly into the foundation of the building which helps to keep it secure and prevents collapse.
These walls also benefit from the weight of the soil that is in front of the wall. This helps to ensure stability across the structure.
One of the biggest advantages of cantilever retaining walls is that they don’t take up as much space as other options. However, the construction process does need space behind the wall so they may not be suitable to support slopes that already exist.
Anchored Retaining Wall
If you are working in an area where space is limited, you will need to construct a thin wall.
This is where anchored retaining walls are typically used.
In particular, they’re suitable for areas where loose soil can be found over rocks. It is possible to build these walls at tall heights due to their construction method. This involves using deep wires or cable rods which are driven horizontally into the earth before concrete is poured to anchor them in position – hence the name.
Sheet Pile Retaining Walls
This type of retaining wall uses sheet materials rather than concrete which is typically utilised in pile walls.
Most pile walls are built by driving concrete into the ground at a deep enough level to withstand any forces that impact them.
Sheet pile retaining walls are built in much the same way as the concrete pile versions but use steel sheets instead. They are installed into sloped land and can be excavated to a deeper level if required. However, these walls struggle to withstand as high a pressure as concrete walls and can only be used to heights of up to 20 feet.