Poured Concrete Retaining Walls: Process, Cost & Durability
Poured concrete retaining walls — also known as cast-in-place concrete walls — are among the strongest and most durable retaining structures available. For Brisbane projects requiring maximum strength, longevity, and design flexibility, poured concrete is often the material of choice.
How Poured Concrete Walls Are Built
The construction process for a poured concrete retaining wall involves several stages:
- Excavation: The footing trench is dug to the engineer’s specification, typically 400mm to 600mm deep
- Steel reinforcement: Rebar cages are tied and positioned according to the engineering drawings. Steel starter bars connect the footing to the wall stem
- Footing pour: Concrete is poured into the footing forms and the starter bars are set in position
- Formwork: Timber or steel formwork is erected on both sides of the wall stem, creating the mould for the wall
- Wall pour: Concrete is pumped into the formwork. Vibration ensures the concrete fills all voids and compacts around the steel
- Curing: The concrete must cure for a minimum of 7 days before formwork removal and 28 days before backfilling
Concrete Specifications
Retaining walls typically use N32 or N40 grade concrete with a minimum cement content appropriate for the exposure conditions. In Brisbane, where soils can be mildly aggressive, the engineer may specify additional cover to reinforcement or higher-grade concrete for durability. Compared to concrete block walls, poured concrete walls have no joints and can be formed to any shape or profile.
Finishing Options
One advantage of poured concrete is the range of finishes available:
- Off-form finish: The natural concrete texture from the formwork, either smooth from steel forms or textured from timber boards
- Rendered and painted: A cement render coat applied and painted in any colour
- Exposed aggregate: The surface layer is washed away to reveal decorative aggregate
- Stone veneer: Natural or manufactured stone tiles applied to the concrete face
Cost Expectations
Poured concrete walls are at the higher end of the cost spectrum due to formwork, concrete pumping, and labour requirements:
- Up to 1.5m height: $500 to $900 per lineal metre
- 1.5m to 3m height: $900 to $2,000 per lineal metre
- Over 3m height: $2,000 to $3,500+ per lineal metre
For cost comparisons with other wall types, review the detailed retaining wall cost guide.
Durability and Lifespan
A properly designed and constructed poured concrete retaining wall can last 50 to 100 years or more. Concrete is impervious to termites, does not rot, and gains strength over time. It is the preferred choice for critical infrastructure and high-load applications.
Get a Poured Concrete Wall Quote
Poured concrete walls demand precision construction. Connect with licensed retaining wall builders in Brisbane experienced in cast-in-place concrete construction for your next project.