What is block paving?

Block paving (also called concrete block paving or CBP) is a hard-landscaping surface formed from individual concrete or clay blocks (pavers) laid on a levelled sand bed over a compacted granular sub-base. The blocks are laid in an interlocking pattern (herringbone, basketweave, or stretcher bond) and jointed with kiln-dried sand, which is vibrated into the joints to lock the blocks together. The result is a strong, flexible surface that distributes vehicle loads without cracking and can be lifted to access services beneath.

What sub-base is needed for block paving?

A minimum 100mm compacted layer of Type 1 MOT (crushed aggregate, well-graded) sub-base is required for pedestrian and light vehicle use. For heavier vehicles or weaker ground, 150mm or more may be needed. The sub-base should be compacted with a vibrating plate compactor in layers not exceeding 100mm. Over the sub-base, a 40-50mm sharp sand laying course is screeded level. The block thickness for a standard driveway is 80mm concrete block or 50-65mm clay paver on a bound base.

Do I need planning permission for a driveway?

Since 2008, planning permission is required for front gardens and driveways over 5m2 if the surface is impermeable (such as traditional block paving). If the surface is permeable (such as permeable concrete blocks, gravel, or a permeable resin-bound surface) or if drainage is directed to a lawn or border, planning permission is not required for domestic driveways under the Permitted Development Rights. This rule aims to reduce surface water runoff from paved front gardens that can cause flooding of drains and roads.

What is the best pattern to lay block paving?

Herringbone (45-degree or 90-degree) is the strongest interlocking pattern and is recommended for driveways and areas subject to vehicle loading, as it spreads loads in multiple directions and prevents the blocks from drifting. Stretcher bond (running bond, like brickwork) is simpler to cut and lay but provides less interlock and is better suited to pedestrian areas and paths. Basketweave is a traditional pattern giving a square, symmetrical appearance but with the least interlocking strength of the three. Clay pavers are laid in the same patterns as concrete blocks.

External Works noun

Block Paving

/ blɒk ˈpeɪvɪŋ /

Also known as: concrete block paving, CBP, clay pavers, interlocking pavers, sett paving

Definition

Block paving is a hard-landscaping surface made from individual concrete or clay blocks (pavers) laid in an interlocking pattern on a sand laying course over a compacted granular sub-base. Kiln-dried sand is vibrated into the joints to lock the blocks together and form a strong, flexible, load-bearing surface. It is widely used for driveways, paths, patios, and car parks. The unbound construction allows blocks to be lifted and relaid to access buried services, and allows the surface to flex slightly with ground movement without cracking.

In practice

A standard residential driveway requires: excavation to 250-300mm below finished level; 150mm compacted Type 1 MOT sub-base; 40-50mm sharp sand laying course screeded to falls; 80mm concrete blocks (or 65mm for clay) laid in herringbone bond; edge restraints (haunching concrete or plastic edging); and kiln-dried jointing sand vibrated in with a plate compactor. The key to a long-lasting surface is full compaction of the sub-base in layers and ensuring edge restraints are fixed before the blocks are laid.

Since 2008, new or replacement front garden driveways over 5m2 must use a permeable surface or include drainage directed to a soakaway - standard impermeable block paving now requires planning permission. Permeable concrete blocks (with open joints filled with gravel, or featuring open-topped channels) satisfy this requirement without planning permission. Weed membrane under the sand bed reduces but does not eliminate weed growth in joints - regular weed killer treatment is the normal maintenance approach.

Building Regulations

Planning (impermeable)Requires householder planning permission for front gardens over 5m2

Planning (permeable)Permitted Development - no planning permission needed

Block standardBS EN 1338 - Concrete paving blocks

Sub-baseType 1 MOT to BS EN 13285

The requirement for permeable surfaces for front garden driveways derives from the Town and Country Planning (General Permitted Development) Order 2008, which removed Permitted Development rights for impermeable surfaces in front gardens in England. Permeable block paving (BS EN 1338 permeable blocks, or traditional blocks with open gravel-filled joints) qualifies as a permeable surface. In conservation areas, planning permission may also be needed for any change of material at the front of the property regardless of permeability.

Full Building Regulations guidance

Related Calculators

Aggregate & Ballast Calculator

Block Paving

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