How Much Does a Retaining Wall Cost on the Gold Coast?

Prices per metre

Retaining Wall Cost per Metre on the Gold Coast

Retaining walls are priced per lineal metre, meaning per metre of the wall’s length at a stated height. On the Gold Coast that runs from $195 a metre for treated pine sleepers to $785 for a gabion wall, supplied and installed. Concrete sleepers, typically $440 a metre, sit in the middle of the range.

Multiply by the length and you have a rough budget for the wall itself. The same guide prices three whole walls, which is the number most people are really after.

Real quotes can land well above the guides. One South East Queensland homeowner posted a quote of $30,000 for a single wall 15 metres long and 1 metre high, about $2,000 a metre. A rate per metre assumes a clear site, an easy dig and a machine that fits down the side of the house.

Materials

Which Retaining Wall Material Costs Least?

Treated pine sleepers are the cheapest wall to build, at $195 to $440 a metre on the Gold Coast. Concrete sleepers and block cost more on the day but don’t rot. Sandstone and boulders sit at the top and the middle of the range, and the price depends heavily on how the stone gets to the wall.

Concrete sleeper retaining wall cost

A concrete sleeper wall costs $295 to $590 a metre at 1 metre high on the Gold Coast, typically about $440. At 1.5 metres that rises to $390 to $930 a metre. The sleepers slot between galvanised steel posts set in concrete, and the post spacing and depth come from the manufacturer’s tables for the wall’s height and the soil.

Timber sleeper walls

Treated pine runs $195 to $440 a metre and hardwood $275 to $590. In Queensland, the treatment classes for timber in contact with the ground are H4 and H5, which is worth checking on any quote that just says “sleepers”.

Sandstone retaining wall cost

A sandstone block wall costs $345 to $685 a metre on the Gold Coast, typically about $540. A standard block is about 500 by 500 by 1,000mm, a quarter of a cubic metre of stone, and the supplier recommends unloading it by machine. Where a truck or excavator can’t reach the wall, every block costs more to place.

Stone and rock retaining wall cost

A boulder or rock wall costs $245 to $590 a metre on the Gold Coast, and a gabion wall of rock in wire cages $295 to $785. Rock already on the block can cut the stone bill. On one of our projects, rob logie wrote, the team was “re-using bush rock as steps on the side of the villa”.

Prices per m²

What Does a Retaining Wall Cost per m2?

A price per m² is per square metre of the wall’s face, and you get it by dividing the price per metre by the wall’s height. A 1.5 metre concrete sleeper wall at a typical $590 a metre works out at about $393 per m². Airtasker’s national guide prices walls this way.

The two units can make the same wall look like two different prices. A wall half a metre high at $300 a metre is $600 per m², so check which unit each quote uses before you compare them. It’s the price per kilo against the price per bag.

Height

How Does Height Change the Cost of a Retaining Wall?

Height changes the price more than anything else. Australia-wide, a wall under 500mm costs $100 to $250 a metre, and one between 1.5 and 2 metres $550 to $1,500. A taller wall holds back more soil, so it needs deeper footings, more steel, more drainage and, once it needs approval, usually an engineer.

On the Gold Coast, engineering costs $490 to $1,950 a job and a soil report $490 to $2,450. In Queensland, that design must come from a registered professional engineer (RPEQ) or someone working under one’s direct supervision. Hillside lots can also sit on the City’s landslide hazard map, which is worth checking before you plan a deep cut.

The rules

Do You Need Approval for a Retaining Wall on the Gold Coast?

You don’t need building approval if the wall and the soil it holds total no more than 1 metre, nothing bears on the soil behind it, it’s at least 1.5 metres from a building or another retaining wall, and it isn’t part of a pool fence. That’s the Building Regulation 2021, schedule 1. Otherwise, approval costs about $440 to $1,775.

Two details catch people out. The height is measured from the finished ground level, after the landscaping is done. And the “surcharge” the regulation rules out means weight that compresses the soil behind the wall; people, cars driving over it and rain don’t count.

The City of Gold Coast adds its own conditions to the exemption. The wall can’t sit over a sewer or stormwater line, in an easement or covenant area, or in a waterfront or oceanfront setback, and the wall and any fence on top must total less than 2 metres. Stormwater from the work can’t be concentrated onto your neighbour’s land.

Near a pool, a wall on the outside of the fence can also become a foothold. QBCC requires a 900mm non-climbable zone outside a pool barrier, so the wall’s position and height are planned with the pool landscaping around it.

Hidden costs

What Else Should a Retaining Wall Quote Include?

A full quote lists the drainage behind the wall, any old wall coming out, engineering, approval and a soil report where they apply, plus excavation and taking the spoil away. On the Gold Coast, drainage alone adds $29 to $78 a metre. A quote that leaves them out looks cheaper until they’re added back in.

Drainage

Water building up behind a wall is a common cause of retaining wall failure, because wet soil pushes harder than dry soil. The Gold Coast cost guide points to the heavy rain of February and March. A wall with no drainage ends up holding back water as well as soil, and it was never built to be a dam.

Access and digging

Where a mini excavator can’t fit down the side of the house, footings and post holes are dug by hand and materials carried in, so labour time climbs. Our excavation work is planned with the wall for that reason. Before any digging, a Before You Dig Australia request finds the pipes and cables underground.

Neighbours

Who Pays for a Retaining Wall on a Boundary?

In Queensland, a retaining wall isn’t treated like a dividing fence. The Neighbourhood Disputes (Dividing Fences and Trees) Act 2011 shares the cost of fences between neighbours, but retaining walls “are not normally a matter of joint responsibility”, the Queensland Law Handbook says, because a wall usually benefits one side more.

The City of Gold Coast suggests speaking to your neighbour before work starts if the wall affects them, and recommends keeping a wall at least 600mm from a side boundary. Where a wall is shared or disputed, agree the cost in writing or get legal advice first.

Licences

Who Can Build a Retaining Wall in Queensland?

A retaining wall worth more than $3,300, labour, materials and GST included, needs a QBCC-licensed contractor and a written contract. The licence class matters too. QBCC’s structural landscaping licence covers retaining walls only “of a height that do not require an engineering certification under a local law”.

So for an engineered wall, check what the contractor’s licence covers, not just that they have one. Bella Terra builds its retaining walls under a Builder - Low Rise licence, QBCC 15452813. Deposit caps and the cooling-off period are in our landscaping cost guide.

From the field

How We Price a Retaining Wall

Bella Terra doesn’t publish prices, because the same wall costs different money on different blocks. We price a wall after seeing the site: the fall of the ground, the soil, what sits above the wall, the access and whether it needs approval. The quote is free, prepared on site and carries no obligation.

1. We walk the slope with you. Dion looks at where the ground falls and how you want to use the level space the wall makes.
2. We measure the height that counts. The wall plus the soil it holds, from the finished ground level, against the 1 metre limit.
3. We check what loads it. A house, a pool, a driveway or a boundary nearby changes the design and the approval.
4. We settle the material, footing and drainage. An engineer designs the wall where the rules call for one.
5. The quote lists every part. The wall, the drainage, the dig, the spoil and any approval, each on its own line.

Customers notice when a wall is done properly. Diane wrote in a Google review that the team worked “at a very competitive price” and that “the new retaining wall is very high quality and is admired by everyone.” Dion replied that he was glad to “build something to last the test of time!”

Design matters as much as the build. rob logie wrote that Dion “made some valuable suggestions on the design and layout, particularly in relation to the retaining walls which significantly improved the design and finish overall.” You can see more finished work in the gallery.

Questions

Retaining Wall Cost Questions