A retaining wall holds back soil, and that job is harder than it looks. The cost reflects the engineering behind it, not just the bricks you can see. Here is what moves the number.
Height is the biggest factor
The taller the wall, the more load it holds, and the more it costs per metre.
- Low walls. A garden bed edge or a small step in the yard is straightforward.
- Anything over a metre. This often needs engineering and council approval in Melbourne, which adds cost but is not optional.
- Tall or tiered walls. More reinforcement, bigger footings and sometimes a stepped design to handle the load.
What sits behind the price
Most of the cost of a retaining wall is in the parts you never see once it is finished.
- Footings. A retaining wall lives or dies on its footing. Reactive clay soils around Melbourne often mean more concrete and steel.
- Drainage. Water behind a wall is what destroys it. Proper agg drain, gravel backfill and weep holes are essential, not extras.
- Reinforcement. Steel in the footing and core filling for block walls all add up.
- The soil itself. A wall holding back a heavy clay bank works harder than one edging a flat bed.
Materials and access
The material changes both the look and the cost.
- Brick and block. A solid, long lasting wall when built properly with the right footing and drainage.
- Access. Getting a mixer, materials and spoil in and out of a tight Melbourne block is slower and dearer than an open site.
- Excavation. Digging the footing and clearing soil behind the wall is a real part of the job, especially in rocky or clay ground.
A cheap retaining wall is no bargain if the drainage is skipped and it bulges or fails in a few winters. The footing and the drainage are where the money should go.
Send through a photo of the slope and your suburb, with a rough idea of the length and height, and we will give you a proper figure for a wall built to hold.