Driveway & Hard Paving
Road Base / Crushed Rock Calculator
Calculates tonnes or tons of crushed stone sub-base for driveways
Updated 26 June 2026 · Live
What this tool does
Calculates tonnes or tons of crushed stone sub-base for driveways.
Formula Used
Spotted something off?
Calculations or display — let us know.
People also use
How the sub-base / road base calculator works
Calculates tonnes or tons of crushed stone sub-base for driveways. The calculator takes your dimensions and supplier rates, applies a standard Australian trade formula, and returns a quantity with an indicative cost. Every figure is an estimate — site conditions always move the final number.
Typical Australian drainage and earthworks wastage
Excavated soil bulks up 15–35% when lifted, so skip bin capacity fills faster than the in-situ volume suggests. Plan for a 1.25× factor when hiring away muck. Our defaults reflect common Australian trade allowances, and can be adjusted upwards for non-standard geometry or downwards where experience supports a lower figure.
What this tool does not do
It does not replace a professional quote, factor regional pricing, assess structural adequacy, or confirm National Construction Code (NCC) compliance. Those remain the responsibility of a suitably qualified designer, surveyor, or your building surveyor.
On-site considerations for sub-base / road base
Excavations over 1.2 m deep need shoring or battered sides — the HSE guidance on trench collapse is not optional. Check for buried services with a CAT scanner before digging.
the National Construction Code (NCC) and compliance
Foul and surface water drainage to a public sewer is governed by the National Construction Code and Sewers for Adoption. Soak wells need a permeability test (BRE 365) to size correctly. When in doubt, a pre-application enquiry to the local council can give early clarity, which tends to be less costly than retrospective correction.
Before you order
Buy plastic drainage pipe in standard 3 m or 6 m lengths with integral seal joints. Cutting short lengths on site wastes material and fittings. Cross-checking the calculator’s output against a supplier quote helps catch differences in pricing assumptions — ask for exact product specifications (grade, finish, batch number) and confirm delivery timescales against your programme.
Adjusting the defaults
Every input in this calculator is editable. Enter your own dimensions, supplier prices, and wastage allowance — the output recalculates instantly. If the defaults feel off for your region or project type, your own numbers always override them.
Using this sub-base / road base calculator alongside other BuildMetricLab tools
This calculator works best as part of a planning workflow. Pair the quantity with our project contingency, labour-hours, and material-cost calculators to build a complete estimate before you pick up the phone to a supplier. All BuildMetricLab tools run entirely in your browser — no sign-up, no data sent anywhere, and every formula is shown on-page so you can audit the maths.
Sources & methodology
Calculates tonnes or tons of crushed stone sub-base for driveways. Every result is calculated from the values you enter, and all inputs are editable.
Frequently asked questions
Are sub-base / road base calculator results accurate enough to order materials?
Use them as a starting estimate only. Verifying the final quantity with your supplier or contractor before ordering is good practice — site conditions, wastage and cut-offs all affect the true figure.
What wastage percentage should I use?
The calculator defaults to the typical Australian trade allowance for drainage & earthworks. Increase it for complex cuts, awkward shapes, or first-time DIY. The default wastage allowance reflects common trade practice; values lower than the default may underestimate offcuts.
Does this replace professional advice?
No. This tool is a planning estimator. For works that affect structure, the National Construction Code (NCC), boundary or dividing-fence, gas, electrics, drainage to a sewer, or similar, consult a suitably qualified professional.
Can I change the unit prices?
Yes — every price field is editable. Plug in your supplier's quote to get a total that matches your project.
Related tools
Calculators from other categories that planners often reach for next.