Block Paving Calculator (UK)
Last updated: 12 August 2026
Work out how many block pavers you need for a driveway or patio, plus the MOT Type 1 sub-base, laying course sand and kiln-dried jointing sand.
How the calculation works
Blocks per square metre comes from the block face area — a 200 × 100mm block is 0.02 m², so 50 fit in a square metre. We add a cutting allowance because edges, curves and herringbone patterns all generate offcuts.
The sub-base is calculated at your chosen depth using MOT Type 1 at about 2.2 tonnes per cubic metre compacted. The laying course assumes 50mm of sharp sand, and jointing sand roughly 5kg per square metre brushed into the joints.
Driveway build-up
| Layer | Driveway | Patio / path |
|---|---|---|
| Excavation depth | ~250mm | ~200mm |
| MOT Type 1 sub-base | 150mm compacted | 100mm compacted |
| Sharp sand laying course | 50mm | 50mm |
| Block thickness | 50–60mm | 50mm |
Edge restraints on a haunched concrete bed are essential — without them the blocks creep outwards and the pattern opens up. Falls of about 1:60 should run away from the property.
Frequently asked questions
How many block pavers are in a square metre?
A standard 200 x 100mm block covers 0.02 square metres, so there are 50 blocks per square metre. 200 x 200mm blocks give 25 per square metre and 200 x 125mm give 40.
How much sub-base do I need for a driveway?
150mm of compacted MOT Type 1 is the standard for a domestic driveway, which is about 0.33 tonnes per square metre. A 30 square metre driveway needs roughly 10 tonnes.
How much sand do I need for block paving?
Allow 50mm of sharp sand for the laying course — about 0.085 tonnes per square metre — plus roughly 5kg per square metre of kiln-dried sand brushed into the joints once laid.
What wastage should I allow for block paving?
Allow 5% for a simple rectangular area and 10% for curves, circles or herringbone patterns, which generate far more cuts at the edges.
Do I need planning permission for a driveway?
In England, permission is not usually needed if the surface is permeable, or if rainwater can drain to a border or soakaway within your property. Laying an impermeable surface over 5 square metres that drains to the road normally does require permission — check with your local authority.
Related calculators
Aggregate Calculator
MOT Type 1, gravel, sand or topsoil — tonnes and bulk bags.
Concrete Calculator
Slab and footing volumes in m³, with bag counts or ballast & cement.
Estimates are for guidance only. Material dimensions, densities and coverage vary by supplier — always confirm quantities before ordering, and consult a qualified professional for structural work.