A clean, low-maintenance alternative to timber, set into galvanised steel H-beam posts on proper footings and drainage. Built by a QBCC-licensed team.
Composite sleepers give you a warm, timber-style look without the upkeep. They won't rot, warp or split, and they don't need oiling or staining to keep looking good. They're lighter than concrete, which makes them a great fit for garden beds, terraces and lower walls, especially where access is tight.
We install composite sleeper retaining walls across Brisbane, Logan, Ipswich, the Redlands and the Gold Coast, from our base in Underwood. They're a popular choice for raised garden beds, terraced yards, pool surrounds and low boundary walls, giving you the look of timber with the low maintenance of a modern material, all set on galvanised steel posts and proper drainage.
The sleepers sit in galvanised steel posts set in concrete footings, so the frame of the wall is built to last.
Composite holds its look without the yearly maintenance timber needs. A hose-down is usually all it takes.
Lighter sleepers are easier to get into backyards with limited access, and suit garden and terrace walls.
Every wall gets proper drainage behind it, because water pressure is what pushes walls over.
In Brisbane, a retaining wall generally does not need building approval when all of these are true: the total height of the wall and the ground it retains is no more than one metre above natural ground level; it’s at least 1.5 metres from a building or another retaining wall; and there’s no surcharge loading (like a driveway, pool or another wall) in the zone behind it. It also can’t form part of a pool-safety barrier.
Once a wall is over a metre, close to a building or another wall, or carrying extra load above it, it typically needs engineering and building approval from a licensed certifier. Heights can also be combined where walls are stacked or terraced. We’ll tell you exactly where your job sits when we assess the site, and arrange engineering when it’s needed.
This is general information based on Brisbane City Council guidance and can change — it isn’t formal advice for your specific site. Requirements differ between councils (Brisbane, Logan, Gold Coast and others) and always depend on the actual conditions on your block. We’ll confirm what applies to your job.
Nearly every failed wall we’re called out to comes down to the same two things: drainage and footings. Water builds up behind a wall with nowhere to go, the pressure doubles, and the wall gives. Or the footings were too shallow for the load. Both are invisible once the job’s done — which is exactly why cheap walls look fine on day one and lean by year three.
That unseen groundwork is the whole point of how we work. We’re built for what’s behind the line.
Retaining walls are priced per lineal metre, not per square metre. As a broad guide, they commonly run from around $200 to $2,000+ per lineal metre, depending heavily on height, wall type, drainage, engineering, site access and how much excavation is involved. A low garden sleeper wall sits at the lower end; a tall engineered concrete wall at the upper. The only real number is a measured quote — and ours is free.
Figures are general market ranges for guidance only, not a quote.
Often yes — but only if the wall was designed for it. The extra height and wind load a fence adds has to be planned into the wall and its footings from the start. If you’re considering both, tell us early and we’ll design them to work together — a Colorbond or timber fence set properly on a wall built to carry it.
Generally not if the retained height is under one metre, it’s at least 1.5 m from a building or another wall, and there’s no extra load behind it. Over that, or near structures, it usually needs engineering and certifier approval. We confirm what applies to your site.
Walls over about a metre, walls carrying load above them, and stacked/terraced walls typically need engineering. We arrange certified engineering whenever a job calls for it.
Composite suits lower garden and terrace walls where you want a timber-style look with no upkeep. For taller walls or heavier loads, concrete sleepers are usually the stronger choice. We'll recommend what suits your height and soil.
Almost always poor drainage or undersized footings — water pressure building behind the wall, or footings too shallow for the load. Both are hidden, which is why doing them right matters most.
Very little. An occasional hose-down keeps it clean. There's no oiling or staining, and the steel posts and drainage do the structural work.
Tell us about your slope and we’ll assess the site and have a preliminary quote back to you within 24 hours. Servicing Brisbane & the Gold Coast.
