Adelaide is a city built on slopes — from the Hills face to the coastal escarpments, most blocks carry a level change that has to be managed properly. A retaining wall is structural work: it carries real loads, it moves water, and when it is built badly it fails slowly and expensively.
We design and build concrete sleeper, timber and besser block walls to Australian Standard AS 4678, with galvanised steel posts set in mass concrete, engineered drainage behind every wall, and council documentation handled where the wall height or site conditions require it.
Every wall we build follows the same disciplined sequence — set-out, bored footings, steel, concrete, sleepers, drainage, backfill. Scroll through the build below to see exactly how your wall goes together.
Why Adelaide walls fail — and how ours don't
Most of the failed walls we replace died the same way: no drainage behind the face. Adelaide's reactive clays swell hard after winter rain, and a wall that can't shed that water is carrying loads it was never designed for. Every wall we build gets ag-pipe behind the base course, free-draining backfill, and a path for water to leave — before we think about what the face looks like.
Height decides engineering. In South Australia, walls retaining over a metre generally need engineering sign-off, and anything supporting a driveway, pool or structure needs it regardless. We design to that reality from the first site visit rather than discovering it at council.
Sleeper, block or rock
Concrete sleepers between galvanised steel posts are the workhorse: fast, engineered, and honest about what they are. Besser block suits tight curves and rendered finishes. Natural rock walls suit Hills-face blocks where the wall should look like it grew there. We quote the option that fits the load and the budget — not the one with the best margin.
The build — real job, real stages
How your retaining walls goes together.
Straight answers
Retaining Walls — FAQs
Do I need council approval for a retaining wall in South Australia?
In SA, a retaining wall generally needs development approval if it retains more than 1 metre of fill or cut, is within 600 mm of a boundary and over certain heights, or supports a structure or driveway. Walls under 1 metre that don't affect neighbouring land can often be built without approval, but every council interprets site conditions differently. We assess this during quoting and prepare the documentation when approval is required.
Concrete sleepers or timber — which should I choose?
Concrete sleepers cost more up front but are termite-proof, rot-proof and rated for 50+ years, which is why they dominate new Adelaide builds. Treated pine is cheaper and suits low garden walls where the retained height and consequences of movement are small. We'll recommend the right system for the height, soil and budget rather than defaulting to one product.
How much does a retaining wall cost in Adelaide?
As a guide, concrete sleeper walls in Adelaide typically run $450–$750 per square metre of wall face installed, depending on height, access, soil and engineering requirements. A 10 m long, 1 m high wall is commonly in the $4,500–$7,500 range. We quote fixed prices after a site inspection — no rate-per-metre surprises.
What happens to the fence on top of my old wall?
Most boundary walls carry a fence. We remove it, build the new wall with extended posts or fence brackets, and reinstate or replace the fence as part of the same job — one contractor, one clean handover.
Talk to us about your retaining walls project.
Site visits across Adelaide metro and the Hills. Fixed quotes, no obligation.