What’s the best retaining wall material?

Retaining walls help keep elevated soil in place on a property. They're often used in areas with two levels of ground that are either sloped or flat. They appear on many residential and commercial properties to prevent potential disasters in the event of serious flooding and other conditions. A properly designed and installed retaining wall can help protect individuals and property while contributing to the property's aesthetics. To get the most from this installation, it's important to select the right retaining wall material.

At First Response Maintenance, we are often asked what materials would be best for a retaining wall — wood or concrete? The short answer is that it depends on the application. The following is a guide to help choose the appropriate retaining wall material based on your application's unique needs.

Considerations when selecting retaining wall materials

When choosing a retaining wall material, there are some characteristics to keep in mind. These include:

1. Size requirements

The size of the retaining wall needed will influence the type of material you select. For shorter walls that provide minimal protection, for instance, you won't require the most durable materials. Wood, concrete blocks, and stones can stay in place using gravity in lieu of mortar. Meanwhile, you may want to use thick timber or poured concrete that provides more strength for larger walls.

2. Water exposure

Another factor to consider is the level of water exposure the wall will experience. Water could impact walls via humidity, precipitation, rainfall, or flooding. The specific location will dictate how much water will affect the wall design. For example, you'll need corrosion-resistant material with ample durability if a retaining wall is located near a coastline. In this case, it would be best to avoid wood; this material is susceptible to rot.

3. Style

To complement the surrounding property, it's important to consider the style of retaining wall that's most compatible. For a more natural look, stone and wood are often ideal. It's also possible to apply certain finishes and facades to add more visual appeal to retaining walls.

4. Expected or desired lifespan

The type of environment the wall is installed in will also determine which materials to select to maximise the wall's longevity. In corrosive environments, sturdier materials such as concrete can help increase the lifespan of the wall to help you get the most from the installation.

The different retaining wall materials available

Depending on the characteristics you're looking for, the following are some of the specific materials you can choose for your retaining wall.

Treated pine

Treated pine is among the most affordable materials available for retaining wall construction. The pieces of treated pine require minimal anchorage to keep them in place. Also, pressure-treated pine that's rated for ground contact can last for decades once in place.

Hardwood

For increased durability in a wood retaining wall, you may want to use hardwood. This material is more expensive than treated pine. But the right grade will be able to hold up to the pressure from the dirt it holds in place and the water it blocks.

Concrete sleepers

Concrete sleepers are more costly than wood options, but they offer a long lifespan. Coloured or grey options are available for these materials. Also, you can add concrete posts or galvanised steel to enhance the appearance and durability of these materials.

Concrete/besser blocks

Like concrete sleepers, besser blocks are a more expensive option. However, they feature a long lifespan to help increase the longevity of your retaining wall.

Sandstone

It's possible to reconstitute and grind sandstone to make it more malleable and create a more natural look.

Choose the right materials based on your needs

It's important to select the right retaining wall material based on the installation site, your budget, and other requirements. By making the right material selection, you'll benefit from a great-looking retaining wall that's built to last.