How Much Does a Retaining Wall Cost?

Last Updated Jun 2, 2016 · Written by Craig Gibson

Retaining Walls|Renovation Costs

Do you want to make better use of your outdoor area?

A retaining wall may be all you need to to create a backyard that is more practical and easy on the eye. With a range of materials and styles available, you can turn your backyard into a space that suits your lifestyle.

But how much will it cost?

This article will help you work out:

• the different materials used to build a retaining wall
• how much your project may cost
• Who can build your retaining wall

Natural stone stack style retaining wall. © Turf It Artificial Lawns & Landscaping

Types of retaining walls

Some of the retaining wall materials you have to choose from include:

• Timber: Treated pine, treated hardwood and railway sleepers are most typically used.
• Concrete: Aside from poured concrete, you have standard concrete blocks and concrete bricks to choose from to construct a concrete retaining wall.
• Brick is a perennial favourite. If you've had a little bricklaying experience and your wall is not too high, you may be able to get good results. If your results are less than perfect, you can always render the bricks after you're done.
• Natural stone boulders make great retaining walls. Expect it to be more than a quick weekend project, though, because part of the art of stacking boulders is finding the perfect fit. That takes time.
• Retaining wall block systems are available that are ideal for a DIY retaining wall project..

Concrete besser block retaining wall. © Garden Effects

Read: 5 Top retaining wall design ideas

Retaining wall regulations and licensing

Most states require retaining wall builders to be licensed. Depending on where you live this could be a builder, landscaper or bricklayer.

If the height of your wall approaches 1 metre, assume you will need to employ a structural engineer. Throughout Australia, the services of a structural engineer are required by law for all retaining walls over a metre in height and in some areas the minimum height may be as low as 600mm. If your retaining wall is less than 1.5 metres away from your property line or another building, you will probably need council approval to build it, no matter how high it is.

The height of a retaining wall isn't the only reason why you may need to have your retaining wall designed by a structural engineer, either. The position of a retaining wall can be an important factor, too. If you want to build one on or near your boundary, you may need to get council permission regardless of its height.

#hiptip: Check with your local council before you build a retaining wall of any height

Read: Understanding retaining wall height regulations

Stone wall retaining wall. © Caroline Dawes Gardens

Hiring a retaining wall builder

When it comes time to hiring a retaining wall builder, take time to make sure they are right for your job. Some questions to ask then include:

• Are you licensed or qualified?
• Are you insured?
• How long will my job take?
• Can you provide a written quote?
• Do you have references I can follow up?
• Can I see examples of your work?

How much does a retaining wall cost?

A number of factors will influence the cost of your retaining wall, specifically:

• Size and scale
• Height
• Materials utilised
• Design, including excavation and drainage requirements

Small retaining walls could be built for under a thousand dollars and escalate to as much as ten thousand dollars. A low cost retaining wall can be built with untreated pine, but will have a limited lifespan and structural integrity. For superior longevity opt for treated hardwood, concrete, brick or stone. This will however cost more. Alos expect to pay more for retaining walls that require council approval and structural diagrams, all additional costs which you will be liable for.

Other considerations that will affect overall cost include excavation and drainage requirements for your site.

Expect to be quoted based on materials and labour, with materials calculated on a per square metre basis.

#hiptip: A structural engineer needs to supervise your retaining wall if it is over a metre in height

Expect to pay:

• $250 to $350 per square metre for treated timber (pine)
• $300 to $450 per square metre for treated timber sleepers (hardwood)
• $300 to $550 per square metre for sandstone blocks
• $400 to $680 per square metre for reinforced concrete blocks
• $550 to $700 per square metre for concrete besser blocks

Read: How much does it cost to landscape a garden?

Getting quotes from retaining wall builders

Before you start getting quotes, have another look at the area where you want your retaining wall. Is excavation necessary? Will there be any access problems for excavators or materials? Do any trees or boulders need to be removed? Look for anything that could add to the cost of the job.

Now that you know what to ask for, you can get quotes from retaining wall experts in your area online and be more confident that the initial quotes you receive will be closer to the actual cost of your retaining wall.

The best way of finding out the cost of your project is to get quotes from local retaining wall builders. This will give you a sense of what market rates currently are.

* All the costs and prices quoted were sourced at the time this article was written. They are indicative, may vary locally, are subject to market forces and should only be used as a guide.