The Different Types of Retaining Walls

retaining walls

Retaining Walls Perth may look like simple stacked stone, brick, or concrete blocks, but they are carefully engineered systems that wage an ongoing battle against gravity. They increase usable space on sloped property and prevent erosion and runoff problems.

Any retaining wall over 4 feet tall requires an engineer’s stamp and footings.

Brick offers both durability and aesthetic appeal, making it a great choice for creating a strong retaining wall. It is available in a wide range of colors, sizes, and textures, making it easy to find the perfect design to complement your landscape. In addition, brick can be curved or angled to create unique shapes and structures that add visual interest to your home.

When choosing brick for your retaining wall, you’ll want to consider the purpose of the structure and what other elements will be built on or around it. Some retaining walls are designed to support patios or walkways while others are intended to hold soil in place for gardening and landscaping purposes. A retaining wall built to support other structures will need to be designed with additional reinforcement to prevent collapse under the added stress.

Retaining walls can also be used to direct the flow of water, preventing runoff from wearing down or eroding the surrounding landscape. This feature is especially important if the retaining wall is located near a body of water.

If you’re considering a brick retaining wall, you’ll need to have the proper tools and knowledge to build it correctly. Bricks aren’t as DIY-friendly as concrete blocks, so building a retaining wall of any significant height should be left to professionals who are up to speed on state and local building codes and regulations.

To start, knock the flange off each block with a hammer before starting to build your retaining wall. Lay one block down on the base, then use a carpenter’s level to make sure it is perfectly level left-to-right and front-to-back. Use the same process to lay down each subsequent course, making sure that the seams of the blocks are offset by half a block.

When you’re ready to install the next course of your retaining wall, it’s important to fill the space directly behind the new block with gravel or sand, not dirt. Dirt swells when saturated, increasing the pressure on the back of your retaining wall, whereas gravel and sand don’t. This will help reduce the stress on your retaining wall and increase its longevity.


Retaining walls made from stone can add a touch of beauty and sophistication to your landscape design. In addition to blending into your yard’s natural environment, stone retaining walls are durable and easy to maintain.

If you choose to build your retaining wall from cut stone, it’s important to plan ahead to ensure you have enough materials for the project. If possible, sort the stones into piles based on size and shape. For example, the largest, flattest stones can be saved for the foundation of the retaining wall, while the narrower, more rounded rocks should be reserved for the top layer of the wall. If you’re building a taller retaining wall, you may need to chisel away peaks and other forms from the stones in order to fit them together tightly.

You can also use concrete blocks designed specifically to form a solid and sturdy retaining wall. The interlocking blocks have a flange on the back side that slips neatly over the course of block before it, allowing the wall to slope gently down as you lay each successive course. Whether you’re using cut stone or block, it’s essential to use a carpenter’s level to make sure the first course of your wall is perfectly even and aligned with its neighboring course.

When building a retaining wall from stone, it’s important to plan ahead for drainage. This helps to prevent hydrostatic pressure from building up behind the wall and damaging it. To help with this, install perforated drainage pipes at the base of your retaining wall. Next, place gravel backfill around the drainage pipes to allow water to flow freely through the pipe.

Many cities, towns and municipalities require a professional engineer’s signature or seal or some other type of certification for any retaining wall that exceeds three feet in height. Additionally, retaining walls made from stone must have flat metal ties at 3-foot intervals along the length of the wall to hold the integrity of the structure.

In addition to helping the wall remain stable, the ties can be covered with mulch or other plants for added curb appeal. In terms of maintenance, regular watering is required to keep the soil moist so that it doesn’t dry out and crack the stone.

Poured Concrete

Poured concrete is the material most commonly seen in retaining walls on a large scale, such as freeway ramps and airport runways. It is strong, offers a variety of design options and blends well with most modern landscaping designs. It is also difficult to construct, however, and requires specialized skill. If it isn’t done correctly, a poured concrete wall can crack or bulge. For these reasons, most landscape contractors avoid using this type of retaining wall in residential projects.

The base of a retaining wall is extremely important. The primary function of a retaining wall is to hold back soil, and the pressure behind that soil can be tremendous. The pressure is concentrated near the base of the wall, where the soil has a wedge shape driven by gravity. If the wall is not properly built, it can collapse under its own weight, causing the soil to slump or even slide downhill.

To prevent this, you should add a layer of gravel or sand to the bottom of your retaining wall footer before filling it with soil. This will help the ground to drain and reduce the chance of water pooling in and around the wall. The wall should also be designed with a proper slope to ensure the water is directed away from your home, which will prevent foundation problems and other costly issues.

If you choose to use concrete block to build your retaining wall, be sure to read the manufacturer’s instructions carefully to determine how much mortar and rebar are needed for each course (row of blocks). These instructions may also contain guidelines on how deep to sink the footer for your particular climate and geology.

You should always seek a professional to build your retaining wall, especially in areas that require a permit or have strict guidelines on how high and where a retaining wall can be constructed. This is the only way to ensure that your retaining wall is safe and stable, and it will last for years to come. A retaining wall that fails can damage your home, cause injuries or property loss, and cost thousands of dollars to repair or replace.


Wood is a natural, versatile and inexpensive material for creating retaining walls. When used with concrete or other more durable materials, it can help create walls that withstand lateral earth pressure. However, a retaining wall made from wood can also be damaged by water or become infested with rodents, so it’s important to use high-quality materials and follow proper construction techniques.

When using wood to build a retaining wall, choose ground contact-rated timbers (also known as pressure-treated lumber). This type of wood has been treated with chemicals that protect it against rot in soil. While it won’t last forever, it is an excellent choice for retaining walls since rot can destroy other more expensive types of retaining wall materials.

Before beginning construction, determine the frost depth in your area and mark it on your retaining wall site. This information will dictate the height of your retaining wall, and it will help you decide what kind of reinforcement to use. If you are building a large retaining wall, consult a professional to ensure that it will be structurally sound.

Dig holes for your retaining wall posts at least 2 feet wide and 3 inches deep. Set a post in each hole and use scrap wood stakes to hold it while the concrete sets. Use fast-setting concrete if possible, as it will set within about four hours.

As you build your retaining wall, stagger each new row of timbers so that they are offset from the previous one. This will prevent the timbers from leaning against each other and will help the wall look symmetrical. Use 60d spikes to secure each timber to the foundation row, making sure to pre-drill holes for the spikes every 8 inches. Once the second row is built, offset each timber again so that the ends are even. Continue this process as you work your way up the retaining wall, securing each timber with 60d spikes every 8 inches and offsetting each successive row of timbers.

When you’re finished, backfill the soil behind your retaining wall with gravel. This will allow water to drain properly, preventing the pooling that can erode concrete blocks and cause the wall to crack or shift. You can also install landscaping plants behind the wall to reduce erosion and add color to your landscape.