How many block paving blocks are in a square metre?

50 blocks for the standard 200 x 100mm format. Divide 1 by the face area in square metres for any other size.

What depth of sub base does a block paved driveway need?

150mm of compacted MOT Type 1 for cars, 100mm for foot traffic only and 200mm or more for vans and heavier vehicles.

Do I need planning permission for block paving?

Usually not, provided the driveway is permeable or drains within your own boundary. Over 5 m² of impermeable paving draining to the road needs permission.

What sand goes between block paving?

Kiln dried sand for standard blocks, swept into the joints and topped up after compacting. Permeable systems use a free draining grit instead.

How long does block paving last?

20 to 25 years or more with a properly compacted sub base, occasional joint sand top ups and careful pressure washing.

Specialist Calculator

Block Paving Calculator UK

Name: Block Paving Calculator UK
Author: CalZone

A driveway order is more than blocks. Our block paving calculator UK tool works out how many paving blocks you need plus sharp sand bedding layer, kiln dried jointing sand and MOT Type 1 sub base underneath, with right wastage allowance for your laying pattern built in.

Length (m)

Width (m)

Sub-base (MOT 1) Depth (mm)

Sharp Sand Depth (mm)

Waste Factor (%)10%

Material Takeoff

UK Standard Note:

Driveway block paving should be at least 50mm thick. For heavy vehicles, 60mm blocks are recommended. Ensure your sub-base is compacted with a whacker plate.

How the Block Paving Calculator Works

Enter length and width of your driveway, path or patio along with your block size. The calculator divides area by face area of a single block, adds your pattern wastage and returns total in blocks and packs.

The benchmark figure worth remembering: standard 200 x 100mm blocks work out at 50 per square metre. A 40 m² driveway therefore needs around 2,200 blocks once 10 percent wastage is added, plus roughly 7 bags of kiln dried sand for the joints.

What Sits Under the Blocks

Block paving is only as good as its build up, and the layers below account for most of excavation:

Sub base: 100mm of compacted MOT Type 1 for patios and paths, 150mm for driveways carrying cars
Bedding layer: 30 to 40mm of screeded sharp sand
Blocks: typically 50 or 60mm thick for domestic work

Total dig depth for a driveway usually lands between 180 and 220mm. On soft ground add a geotextile membrane below sub base and compact Type 1 in layers with a wacker plate. Edge restraints set in concrete around the perimeter stop whole surface creeping sideways under braking and turning loads.

Choosing a Laying Pattern

Pattern choice changes both look and order size. Stretcher bond is simplest with minimal cuts. Herringbone at 90 degrees adds around 5 percent pattern waste while 45 degree herringbone adds closer to 10 percent because every edge needs an angled cut. Herringbone is worth that extra material on driveways though, since the interlock resists the turning forces of car tyres far better than straight courses.

Whatever pattern, order all packs together and check they come from same batch so the colour blend stays consistent across the area.

Drainage Rules for UK Driveways

Since permitted development rules changed, any new front driveway over 5 square metres must deal with its own surface water. You have two compliant routes, use permeable block paving with wider joints filled with free draining grit or lay standard blocks and direct the runoff to a lawn, border or soakaway within your boundary. Draining onto a public highway is not an option and a dropped curb always needs council approval regardless of driveway size.

Permeable paving needs a different build up too, with an open graded Type 3 sub base rather than standard Type 1 so water can pass through rather than pool.

Worked Example: 6m x 4m Driveway

Materials Breakdown (24m² Driveway in 45° Herringbone)

Component	Quantity Required
Area	24 m²
Standard Blocks (200x100mm)	1,200 blocks base (1,320 with 10% waste)
Bedding Sand (40mm layer)	1.5 tonnes (approx. 1 m³)
Kiln Dried Joint Sand	120 kg (5x 25kg bags)
Sub Base (150mm MOT Type 1)	7.5 tonnes

As a budget check, supplied and installed block paving typically runs £45 to £100 per square metre in the UK depending on block choice and region, so materials are only part of picture if you are pricing against contractor quotes.

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