Estimate Concrete For A Poured Retaining Wall, Continuous Footing Or Stepped Wall Run. Enter Metric Measurements, Then Add Your Own Waste Allowance, 20 Kg Bag Yield And A$/m³ Rate.
Calculate The Wall Stem, Wall And Footing Together, A Footing By Itself, Or Multiple Stepped Wall Sections.
This Mode Assumes The Footing Runs The Same Length As The Wall Stem.
Press Calculate Concrete To See The Result.
A Poured Retaining Wall Commonly Has Two Rectangular Concrete Volumes: The Vertical Wall Stem And The Footing Below It. Calculate Each In Cubic Metres, Then Add Them Together.
Keep Wall And Footing Quantities Separate, Then Add Waste, Bags And Concrete-Only Cost.
Length × Height × Thickness In Cubic Metres.
Continuous Concrete Base Calculated Separately.
Add Your Own Percentage For Real Site Variation.
Use The Exact Product Yield You Enter.
Enter Your Own Current A$/m³ Rate.
Save A ConcreteCreek.com Branded Estimate.
A retaining wall concrete estimate begins with geometry. For a cast-in-place wall, the two main concrete volumes are usually the vertical wall stem and the supporting footing. When each component is rectangular and uniform, its volume is calculated by multiplying its three dimensions after converting every measurement to metres.
The calculator is intentionally a quantity tool rather than a retaining-wall design tool. A real wall has to deal with retained soil, groundwater, drainage, surcharge loads, ground conditions, reinforcement and construction sequence. Those issues can change the required dimensions and detailing, but they cannot be determined from a simple cubic-metre formula. Use the dimensions from the actual project design, then use this page to convert those dimensions into a material quantity.
Convert millimetres to metres before multiplying.
For example, a 10 m wall that is 1,000 mm high and 200 mm thick contains 10 × 1.0 × 0.20 = 2.00 m³ of concrete in the wall stem. This does not include the footing, returns, piers, columns, keys, thickened zones or any allowance for real construction variation.
Calculate the footing independently, then add it to the wall stem.
If that same 10 m wall has a 700 mm wide by 300 mm deep continuous footing, the footing volume is 10 × 0.70 × 0.30 = 2.10 m³. The geometric wall-plus-footing total is therefore 4.10 m³ before waste. Separating these two volumes is useful because forgetting the base can produce a major underestimate.
Retaining-wall drawings commonly show wall length in metres while height, thickness, footing width and footing depth are shown in millimetres. Divide millimetres by 1,000 before multiplication. For example, 150 mm is 0.15 m, 200 mm is 0.20 m, 600 mm is 0.60 m and 1,200 mm is 1.20 m.
| Millimetres | Metres | Common Input |
|---|---|---|
| 150 | 0.15 | Wall Thickness |
| 200 | 0.20 | Wall Thickness |
| 300 | 0.30 | Footing Depth |
| 600 | 0.60 | Footing Width |
| 1,000 | 1.00 | Wall Height |
| 1,500 | 1.50 | Wall Height |
Do not automatically multiply the entire wall length by the maximum height when the wall steps down or changes height along the run. Instead, divide the wall into sections with reasonably consistent dimensions. Calculate each section as length × height × thickness and add the results. The Stepped Sections mode provides three segments for this purpose, and unused segments can remain at zero.
Some wall designs include return walls, columns, buttresses, pilasters, edge thickenings or other concrete elements that are not represented by the simple wall stem and footing. Calculate those components separately using the appropriate geometry, then add them to the total. Do not add a feature simply because it is common in another retaining-wall design.
Mathematical volume is exact, but real concrete placement can vary. Footing excavation can be slightly wider or deeper than the nominal dimension, forms can move, bases can contain local low spots and some concrete can be lost during placement or remain in delivery equipment. The waste field lets you add a project-specific percentage rather than forcing one value on every job.
There is no universal percentage that is correct for every retaining wall. Accurately formed work can differ from an irregular excavated footing, and a small hand-mixed job has different logistics from a pumped ready-mix pour. Recheck the built forms and excavation before finalising the order.
Bagged concrete products do not all produce the same mixed volume. Enter the cubic-metre yield from the exact 20 kg product data sheet. The calculator divides the concrete quantity by that yield and rounds up to whole bags. Leaving the yield at zero prevents a misleading bag count.
The cost result is concrete only. It multiplies the calculated quantity by the A$/m³ rate you enter. Reinforcement, excavation, formwork, drainage, waterproofing, labour, pumping, engineering, disposal and other project costs remain separate unless your quote specifically includes them.
The default result shows the calculated volume after your waste allowance without forcing another rounding increment. If you want an upward planning figure, select 0.05 m³ or 0.10 m³. Always compare the final quantity with the supplier's current ordering rules.
Use Final Project Dimensions And Verify Planning, Structural, Drainage And Construction Requirements Separately.
The NSW Planning Portal provides specific guidance for earthworks, retaining walls and structural supports. Whether work can follow an exempt, complying or other approval pathway depends on the applicable standards, exclusions and site circumstances. A concrete result from this calculator does not establish that a proposed wall is exempt from approval or suitable for the site.
The concrete formula does not change when water or soil conditions change, but the engineering problem can. Water behind a wall can increase pressure, and the supporting ground affects how loads are transferred. Drainage, footing dimensions and reinforcement therefore need to follow the actual design rather than assumptions built into a volume calculator.
SafeWork NSW identifies formwork collapse, falls and falling objects among the major risks associated with formwork. Its guidance emphasises planning, safe systems of work, stable foundations, competent involvement where required and appropriate checks before concrete is placed. These requirements concern construction safety rather than volume, but they matter whenever a calculated quantity becomes a real pour.
Cross-check geometry with the Concrete Volume Calculator, use the Concrete Foundation Calculator for foundation-focused work, compare quantities with the Concrete Quantity Calculator, and use the Total Concrete Cost Calculator for broader cost planning.
Examples Demonstrate Arithmetic Only And Are Not Recommended Wall Designs.
| Example | Wall Dimensions | Footing Dimensions | Wall m³ | Footing m³ | Total m³ |
|---|---|---|---|---|---|
| Example A | 5 m × 800 mm × 180 mm | 5 m × 600 mm × 250 mm | 0.72 | 0.75 | 1.47 |
| Example B | 10 m × 1,000 mm × 200 mm | 10 m × 700 mm × 300 mm | 2.00 | 2.10 | 4.10 |
| Example C | 15 m × 1,200 mm × 200 mm | 15 m × 800 mm × 300 mm | 3.60 | 3.60 | 7.20 |
Multiply Wall Length By Wall Height By Wall Thickness After Converting Every Measurement To Metres. Add The Footing Volume Separately If The Wall Has A Concrete Footing.
Yes. Choose Wall + Footing To Calculate The Vertical Wall Stem And Continuous Base In One Result.
Use Stepped Sections And Enter Each Segment With Its Own Length, Height And Thickness. The Tool Adds The Section Volumes Together.
No. Enter The Dimensions From The Actual Project Design.
No. Reinforcement Size, Spacing, Anchorage And Detailing Are Outside This Concrete-Volume Tool.
No. The Result Is Concrete Only.
Enter The Cubic-Metre Yield From The Exact Product. The Calculator Divides Required Volume By Yield And Rounds Up To Whole Bags.
No. It Multiplies Concrete Volume By The A$/m³ Rate You Enter. Other Project Costs Are Separate.
Zero Provides A Clear Reset State. When You Focus A Zero Field It Clears, So Your Typed Number Replaces Zero Instead Of Being Added After It.
No. Check Current Requirements For The Project And Site With The Relevant Authority Or Qualified Professional.
Current NSW Planning Guidance For Retaining Walls And Structural Supports.
Open NSW Planning GuidanceGuidance On Earthworks, Structural Supports And Related Standards.
Open Complying Development GuidanceSafety Guidance For Planning, Erecting, Using And Dismantling Formwork.
Open Formwork GuidanceApproved Code Of Practice For Managing Formwork Risks.
Open The Formwork Code