In Australia, our climate impacts so much, including what fence and retaining wall types we build. Luckily, a retaining rock wall is suitable for almost any environment, never goes out of style and is long-lasting too. It may also increase the value of your property, depending on the market.
Before you start throwing rocks in your garden, you’ll first need to figure out if you truly want to use rock, how much a retaining rock wall will cost and pros and cons of this type of build.
Photo by Fabrizio Conti on Unsplash
Types of Retaining Walls in Australia
Concrete
Concrete retaining walls are long-lasting but can be difficult to match with your house’s exterior design, depending on its look. However, with there being three different types of concrete retaining walls — block, sleepers and poured — there are some options out there to suit almost any home.
Timber
As timber retaining walls give such a great natural look, they can easily be incorporated into almost any garden. Unlike rock and concrete, timber won’t last forever and can be more susceptible to both rot and termites. But, with care, you can help prevent this.
Timber retaining walls come in 2 general types, hardwood sleepers or treated pine logs.
Rock & Stone
Rock and stone retaining walls will look good in just about any garden, due to their natural look and feel. There are also a number of different ways to use the rock, including using large boulders or cut-stone blocks or perhaps a more free-hand style or large rocks built within a metal cage (known as gabion).
While it may be time-consuming and a little pricey to build a retaining rock wall, they do last a long time and need little maintenance.
Brick
Brick is a fantastic material for retaining walls due to its natural strength, longevity and ability to create straight or curved lines. On the other hand, it can be expensive and difficult to make any changes or even replace a damaged brick.
Retaining Rock Walls: Frequently Asked Questions
How much do retaining rock walls cost?
As the cost of your retaining wall will depend on its size, style and materials, the price could range anywhere from $140 to 500m2. If you also need labour, this will normally come at a flat rate, and if you need a structural engineer (see below), this will also increase your costs.
Building your retaining wall yourself will cut the cost of labour, but could also increase the chance of other unexpected costs. Remember, landscapers and retaining wall builders will normally have access to wholesale material prices, which can cut down your overall cost too.
Do retaining walls need council approval?
Whether or not you need council approval for your retaining rock wall will depend where you’re located. However, generally speaking, if your wall exceeds 1m in height, you will need to get council approval before you begin work.
To be on the safe side, check with your local council to ensure your property and where you’d like to build your retaining wall is all within regulation.
Do I need a structural engineer for my retaining wall build?
A structural engineer is someone who looks at the design and build of a structure, such as a retaining wall, to ensure its safety and longevity. For those choosing a DIY retaining wall, you’ll need to get in touch with your local council to ensure you’re meeting all current building regulations.
Or, to save yourself the hassle, you could hire a landscaper or retaining wall specialist to handle the whole process for you, safety check and all. This may also help you save some dollars on hiring additional services.
Retaining Rock Wall Pros & Cons
The Pros
Rock can last forever.
Unlike many other materials, rock is strong and durable, so won’t rot and won’t require protection against termites. In the long run, it means less maintenance costs and work, and no need to have to replace your wall after a period of time.
Retaining rock walls don’t need mortar.
One of the good things about retaining rock walls is you can choose to have mortar or not, depending on the style you’re going for. Keep in mind, not using mortar allows water to flow through the wall, reducing the risk of the wall cracking or bulging. To add extra strength to a mortarless wall and a unique twist, you can add plants between the rocks too.
Rock walls instantly add character.
If you want a natural wonderland for a garden or have a wall that looks like it could have been there for years, a rock retaining wall is for you. Each and every rock is unique in its own way, meaning your rock wall will never quite look like someone else’s.
The Cons
Retaining rock walls are labour intensive to build.
It goes without saying that rocks and boulders can be quite heavy, so if you’re building it yourself, you’ll most likely need some type of excavator. You also need to take into consideration designing the wall, hauling materials, etc.
Rock can be more expensive than other types of retaining wall materials.
As retaining wall builders charge based on materials and labour, you will pay more for rock design and construction. However, if you were to source the rock on your own, you may end up paying more as the landscapers may receive wholesale prices.
You may need to take into consideration the extra cost of machinery hire the company will need to shoulder to do the job if needed.
Boulder retaining walls can be frustrating to build.
Something many people forget when choosing a rougher-edged rock for their retaining wall is how they all work as a giant puzzle. Each rock needs to be perfectly fitted together for the entire structure to be secure, which can take time if you have a strange-shaped rock already placed.
As you can see, hiring a retaining rock wall specialist will save you a lot of time and stress. You can save yourself further hassle by finding one on Localsearch!
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