What it costs to build a retaining wall in Melbourne (by material and height)
Installed retaining wall prices in Melbourne's south-east broken down by material and wall height, including when engineering and permits enter the picture.
We've already published a general retaining wall cost guide with the big picture. This post answers the next question people ask once they've read it: "OK, but what will MY wall cost?" The two variables that decide that are material and height, so here's the price grid we quote from, and the height thresholds where the rules (and costs) change.
Quick answer
Installed prices per square metre of wall face in Melbourne's south-east in 2026:
| Material | Up to 600mm high | 600mm to 1m | Over 1m (engineered) |
|---|---|---|---|
| Treated pine sleepers | $300 to $380/m² | $350 to $450/m² | $450 to $550/m² |
| Hardwood sleepers | $350 to $430/m² | $400 to $500/m² | $500 to $600/m² |
| Concrete sleepers | $400 to $500/m² | $450 to $600/m² | $550 to $700/m² |
| Segmental block (Link, Tasman) | $450 to $550/m² | $500 to $650/m² | $600 to $750/m² |
Remember the maths: a 10 metre long wall at 800mm high is 8m² of wall face. At concrete sleeper rates, that's roughly $3,600 to $4,800 installed with drainage included.
Why height changes the price faster than length
Doubling a wall's length roughly doubles its cost. Doubling its height more than doubles it, because:
- Post depth. The rule of thumb is posts embedded as deep as the wall is high, sometimes deeper on clay. A 1.2m wall needs 1.2m+ holes, bigger augers, more concrete per post.
- Post size. Taller walls move from 100UC steel posts to 150UC, at nearly double the steel cost.
- Soil load. Retained soil pushes harder at the bottom of a tall wall. That's physics you pay for in materials.
- Engineering and permits. In Victoria, walls over 1 metre (or any wall supporting a structure, driveway or fence near a boundary) generally need a building permit and an engineer's design. Budget $800 to $1,800 for engineering and $700 to $1,500 for the permit. Our Casey and Cardinia permit guide walks through exactly when this applies.
A money-saving pattern we recommend a lot: two stepped 800mm walls instead of one 1.6m wall. Terracing often comes out cheaper than one engineered monster, looks better, and gives you a planted garden bed between the tiers.
What's inside the per-metre price
Every price in the table above includes the parts that make a wall last on growth-corridor clay:
- Excavation and post holes
- Posts set in concrete
- Sleepers or blocks
- 100mm slotted ag pipe at the base
- 20mm clean aggregate backfill wrapped in geofabric
- Connection of the drain to stormwater or a legal discharge point
- Site cleanup
If you're comparing our quote against one that's 25% cheaper, the difference is almost always the drainage layer. On Casey clay, a wall without drainage starts leaning within a couple of years. The sleeper comparison post covers how each material handles that moisture over time.
Material picks by situation
Treated pine is the value pick for garden beds and walls under 600mm where the wall is doing light work. Lifespan 15 to 20 years on clay with good drainage.
Hardwood buys a nicer face and a few more years than pine. It suits established gardens where the timber look matters.
Concrete sleepers are what we install most in Clyde North, Officer and Pakenham. 50+ year lifespan, no rot, no termites, and the woodgrain and stone-look finishes have come a long way. The sweet spot for any wall doing structural work.
Segmental block systems suit curved walls, tiered landscaping and anywhere you want a masonry look without rendered besser prices. They're also the easiest to extend later.
Worked examples
Garden bed wall, Berwick. 6m long, 400mm high treated pine wall framing a raised veggie bed. 2.4m² of face. $750 to $900 installed. No permit needed.
Side boundary wall, Clyde North. 12m long, 800mm high concrete sleeper wall holding the neighbour's higher ground, with ag drain to stormwater. 9.6m² of face. $4,500 to $5,500 installed. No building permit (under 1m, not supporting a structure), but we still build it to engineering principles.
Sloping block cut, Pakenham. 15m long, 1.4m high engineered concrete sleeper wall with 150UC posts. 21m² of face at $550 to $700/m² is $11,500 to $14,700, plus roughly $1,800 to $3,000 of engineering and permit costs. Call it $13,500 to $17,500 all up. This is the kind of job where the two-tier alternative is worth pricing.
The questions that move your quote
When you ask for prices, have answers ready for these. They're what we need to give you a real number instead of a band:
- How long and how high (measure the level difference, not the slope)?
- What's above the wall: garden, lawn, driveway, fence, or a building?
- Where can water legally drain to?
- Can a small excavator get to the wall line, or is it hand-dig territory?
- Is the soil clay (in Casey and Cardinia, assume yes)?
Get your wall priced properly
We measure, check the soil, and quote in writing within 24 hours, including drainage and any engineering or permit costs flagged up front, so there are no surprises at invoice time.
- See our full retaining walls service
- Browse local work in Clyde North and Pakenham
- Call (03) 4328 2781 or request a quote