Paving Stone Calculator by Rechnerzentrale

Paved area

m²

Stone width

Stone length

Wastage

Standard 5% – for circular patterns or herringbone laying, plan for up to 10%.

Sub-base: excavation, base course, beddingbedding 4 cm · base course 20 cm

Paver thickness

Bedding (grit)

Assumption 4 cm compacted (typically 3–5 cm)

Base course (crushed stone)

Assumption 20 cm – more for driveways; the contractor sets the thickness based on use and soil

Allowance for compaction

Loose delivery volume vs. compacted layer – assumption 25%

Bulk density crushed stone

t/m³

Bulk density grit

t/m³

Stones needed

1,050pieces

For 20 m² you need 1,050 stones of 10 × 20 cm: 1,000 for the area and 50 as wastage (5%).

Area shown as a square, stones to scale in a running bond

Sub-base: excavation, base course, bedding

Quantities from area × layer thickness; allowance and bulk densities are assumptions – the delivery note and the design take precedence.

How this was calculated

A_S = 0.1 m × 0.2 m = 0.02 m²

n = ⌈20 ÷ 0.02 × (1 + 5 %)⌉ = 1,050

Order all stones from a single delivery. Colour batches can vary slightly and may be visible side by side.