How much road base and sand do I need for pavers? (per m², with a worked example)
Short answer
For a garden path or patio, a typical Australian base is about 50–100 mm of compacted road base plus 20–30 mm of bedding sand, under the pavers. For a 10 m² patio with a 100 mm base, that's about 1.25 m³ of loose road base (roughly 2.3–2.5 tonnes, allowing for compaction) and about 0.3 m³ of sand (roughly half a tonne). Driveways need a much deeper base — check your council's specification.
Most paving problems — sinking, rocking pavers, puddles — come from the base, not the pavers. Getting the depths right, and buying enough material, is most of the job.
How deep to dig
A typical pedestrian path or patio build-up, from the bottom:
| Layer | Depth |
|---|---|
| Compacted road base (crushed rock) | 50–100 mm |
| Bedding sand | 20–30 mm |
| Pavers | Usually 30–60 mm, depending on the paver |
Bunnings’ guide uses 50 mm of compacted road base plus 20–30 mm of bedding sand, so for 30 mm pavers you’d dig about 100–110 mm below the finished surface. A deeper base (around 100 mm) is sensible on soft or clay soils. Council specifications for footpaths use around 25 mm of compacted bedding sand.
Driveways are different. Cars need a much deeper, engineered base, and a driveway crossover to the street has to meet your council’s specification. Check with them before you start.
Working out quantities
Volume (m³) = area (m²) × depth (m)
Road base shrinks when it’s compacted, so order extra — roughly 25% more than the compacted volume. Then convert to tonnes, because landscape suppliers usually sell by weight.
Approximate densities (they vary by supplier — ask for their figure):
- Road base: about 1.8–2.0 tonnes per m³
- Bedding sand: about 1.6 tonnes per m³
Worked example: a 10 m² patio
Road base (100 mm compacted): 10 m² × 0.10 m = 1.0 m³ compacted × 1.25 for compaction = 1.25 m³ loose × 1.8–2.0 t/m³ ≈ 2.3–2.5 tonnes
Bedding sand (30 mm): 10 m² × 0.03 m = 0.3 m³ × 1.6 t/m³ ≈ 0.5 tonnes
Pavers: 10 m² plus an allowance for cuts and breakages. How much depends on the pattern and how many cuts your edges need — straight lay needs the least; herringbone and curves need more. Check with your supplier.
Build steps in brief
- Mark out and excavate to the total depth, sloping the base away from the house so water drains off (a gentle fall is enough).
- Lay and compact the road base in layers, with a plate compactor — several passes each layer.
- Screed the bedding sand to an even depth using rails and a straight edge. Don’t walk on it.
- Lay the pavers, working from a straight edge, and cut the edges.
- Compact the pavers into the sand and sweep jointing sand into the gaps.
- Edge restraint: make sure the edges are held — by a wall, a concrete haunch or an edge strip — or the pavers will creep over time.
Sources
Every rule on this page is taken from these official sources. If a rule has changed, please tell us and we’ll fix it.
This guide is general information, not legal or professional advice. Rules differ between states, councils and individual properties, and they change. Confirm with your state regulator or council before starting work, and if in doubt, get a licensed tradesperson.