Composite Retaining Walls
Fibre-reinforced polymer sleepers that slot between posts to form an interlocking wall that won't rot, rust or corrode. Enter your length, wall height and soil type, and the calculator sizes the posts, footings and drainage and builds your exact parts list.
Composite FRP sleepers from $52 inc GST · won't rot, rust or corrode · 35-year manufacturer warranty · engineered to AS 4678.
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Use the calculator to build your exact, compliant materials list, priced and ready to buy.
Browse Retaining
Sleepers
2 productsSleepers for SuperSleeper composite retaining walls.
Posts
3 productsPosts for SuperSleeper composite retaining walls.
Accessories
4 productsAccessories for SuperSleeper composite retaining walls.
Fixings
4 productsScrews and fixings for SuperSleeper composite retaining walls.
Plinths
4 productsPlinths for SuperSleeper composite retaining walls.
Composite vs timber vs concrete sleepers
Why composite beats timber and concrete
SuperSleeper is a fibre-reinforced polymer (FRP) composite - not timber, not concrete, and not recycled plastic. Because the material is non-organic, there is nothing to rot and nothing for termites to eat, and no steel to rust. It is engineered to resist the long-term deflection that bows timber and the cracking and spalling that chips concrete.
It is also light. A 2.35m sleeper weighs around 5.5kg, so a wall goes together by hand - no excavator slinging sleepers into place, and roughly 30-40% faster than concrete or timber. SuperSleeper backs the material with a 35-year warranty and quotes an expected life of up to 100 years when it is installed and maintained correctly.
| SuperSleeper composite | Timber sleepers | Concrete sleepers | |
|---|---|---|---|
| Rot, rust and termites | Immune - non-organic FRP | Rots, warps and attracts termites | Immune, but can crack and spall |
| Weight and handling | About 5.5kg per 2.35m sleeper, no machine lift | Heavy, manual handling | Very heavy, often needs machinery |
| Cracking and chipping | Engineered to resist deflection | Splits and checks with age | Can crack, chip and spall |
| Finish | Plain grey or Monument, takes paint with no primer | Natural, weathers and greys off | Grey, limited options |
| Warranty | 35-year manufacturer warranty | Varies, often limited | Varies by supplier |
| Expected life | Up to 100 years installed correctly | Shorter in wet or ground contact | Long, but heavy to build |
How a SuperSleeper wall goes together
- Posts first. Composite H and C posts are concreted into footings at roughly 2m spacing. Composite SuperPosts suit walls up to about a metre; taller walls step up to steel posts and an engineered design.
- Bottom sleeper seats on the footing. The concrete supports the base of the sleeper (the SuperSupport locates it), not just its edge.
- Sleepers slide in. Each composite sleeper drops down the channel between the posts, and a SuperWedge locks and levels every course.
- Cap it off. A SuperCap channel finishes the top edge for a clean line.
- Drainage behind the wall. Run SuperDrain (a drainage mat on a roll) or a traditional aggregate-and-agg-pipe bed - drainage is essential, not an extra.
- Add a fence on top. The SuperBracket ties fencing into the wall where you need it.
The calculator turns your length, wall height and soil type into the exact count of each part.
Engineering, height limits and council approval
SuperSleeper is engineered to AS 4678 (earth-retaining structures) and independently tested through a NATA-accredited laboratory and QUT, and the manufacturer can supply engineering certification for its products.
Height drives most of the rules. Composite posts suit walls up to about a metre; above that you use steel posts and an engineered design. As a general rule, any wall over 1 metre needs an engineer and council approval - and the trigger height varies by state and local council (often somewhere between 600mm and 1000mm), so check your local rules before you start.
The calculator sizes your wall to whole sleeper courses (2, 3, 4 or 5 high), matches the posts and footings to your soil type, and hands the jobs an engineer should price - a slope above or below the wall, a driveway, pool or structure near it, a wall stacked over another, water in the ground, or a shared boundary - straight to a tailored quote rather than guessing. We do not publish footing depths here; those come from the engineered design for your site.
Frequently asked
What is SuperSleeper made of?
It is a fibre-reinforced polymer (FRP) composite - glass fibre in a tough polymer - not timber, concrete or recycled plastic. Because it is non-organic, it does not rot and termites cannot touch it.
Will it rot, rust or attract termites?
No. There is no timber to rot or feed termites and no steel to rust. The composite is built for long-term ground contact and holds up to UV and the everyday knocks a wall takes.
How long does it last, and what is the warranty?
SuperSleeper warrants the product for 35 years and quotes an expected life of up to 100 years when it is installed and maintained correctly.
Can I install it myself?
Yes for a garden-scale wall. The sleepers are light (about 5.5kg for a 2.35m length) and slot down between the posts, so there is no machinery slinging them in. Any wall over a metre, or on tricky ground, should be built to an engineer's design.
How high can I build?
Standard composite posts suit walls up to about a metre. Taller walls use steel posts and an engineered design, and anything over a metre needs an engineer and council approval.
Do I need council approval?
It depends on your state and council. The trigger is commonly somewhere between 600mm and 1000mm high, and any wall over a metre needs both an engineer and council sign-off. Check your local rules before you begin.
What colours does it come in?
Off the shelf it is a plain grey, with a Monument option. It also takes exterior paint with no primer, so you can match it to Colorbond colours like Woodland Grey or Monument.
What about drainage?
Drainage behind the wall is essential, not an extra. You can run SuperDrain (a drainage mat on a roll) or a traditional aggregate-and-agg-pipe bed, and the calculator includes your choice in the parts list.
How is it priced?
We are supply-only, so you pay for materials, not labour. Enter your wall's length, height and soil type and the calculator returns an exact parts list - sleepers, posts, caps, wedges, drainage and fixings - with your price.
Build your retaining wall parts list
Enter your length, wall height and soil type, and get your materials list and footing schedule in a few minutes.
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Not sure what you need?
Use the calculator to build your exact, compliant materials list, priced and ready to buy.