Question 1

What is a paver base and why does it need two layers?

Accepted Answer

A paver base provides a stable, level foundation for concrete pavers, natural stone, or brick. The two-layer system uses: (1) a drainage layer of drainage rock (1.45 t/m³) to allow water to pass through and prevent frost heave, and (2) a compacted base of road base (2.0 t/m³) that provides structural support and levels the surface for paver placement.

Question 2

How deep should each layer be for pavers?

Accepted Answer

Standard paver base depths: drainage layer 75–100mm, compacted road base layer 100–150mm. For heavy-duty applications like driveways with vehicles, increase the base layer to 150–200mm. For pedestrian paths and patios, 75–100mm base with 75mm drainage is typical.

Question 3

Why does the base layer use a compaction factor?

Accepted Answer

Road base is ordered as loose material, but it compacts to a smaller volume when installed. A 1.15 compaction factor means you need to order 15% more loose material than the finished depth — 1.15 m³ of loose road base compacts to 1.0 m³ in place.

Question 4

What is drainage rock vs road base?

Accepted Answer

Drainage rock (1.45 t/m³) is washed, angular crushed rock (typically 10–20mm) with no fines — it drains freely and prevents water pooling. Road base (2.0 t/m³) is a graded mixture of crushed rock and fines that compacts to a dense, stable layer — it does not drain as well but provides excellent structural support.

Question 5

Can I skip the drainage layer?

Accepted Answer

The drainage layer is recommended in areas with clay soils or where water pooling is a risk. In well-draining sandy soils, some installers use only a compacted road base layer. However, skipping drainage can lead to water accumulating under pavers, causing shifting, heaving, and paver failure over time.

Question 6

How much paver base do I need for a 30m² patio?

Accepted Answer

For a 30m² patio at 100mm drainage + 150mm base with 10% waste: drainage layer 3.3 m³ at 4.79t, base layer 5.69 m³ at 11.39t. Total about 9 m³ and 16 tonnes. Order separately as two different materials.

Paver Base Calculator

Results

Drainage Layer (drainage-rock 1.45 t/m³)

Base Layer (road-base 2.0 t/m³, 1.15× compaction)

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Two-Layer System

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Results

Drainage Layer (drainage-rock 1.45 t/m³)

Base Layer (road-base 2.0 t/m³, 1.15× compaction)