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Cellular dense concrete blocks offer a lower weight alternative to solid dense blocks with improved thermal properties. Blinded cells on the upper bed face allows for a full bed of mortar and easier build.

Manufactured from Class 2 aggregates and consist of up to 30% recycled raw material. Produced to BS EN 771-3.


  • Inner and outer leaves of external cavity walls up to three storeys.
  • Internal partition walls.
  • Building Regulations (E&W) Approved Document E and Robust Detail acoustic separating walls.
  • BRE Green Guide A+ rated walls.

Manufactured to BS EN 771-3.

Related literature

The following content references this product:

Standard product features

Face size:

440 x 215 mm.

Dimensional tolerance:

Category D1.

Dry density:

1900–2100 kg/m³.

Compressive strength:

Higher strengths are available to order.

Thermal conductivity:

0.88 W/mK (protected inner leaf), 0.92 W/mK (exposed outer leaf).

Fire resistance to BS EN 13501-1:

Class A1.

Configuration to BS EN 1996-1-1:

Cellular, group 2.


Compressive strength:

7.3 and 10.4N/mm³ available as standard, higher strengths are available to order.

NBS Specification

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This product is associated with the following NBS Create clause:
45-80-50/300 Aggregate concrete blocks

NBS Specification

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This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Thomas Armstrong (Concrete Blocks) Ltd


+44 (0)1748 810204

Product reference

Cellular Concrete Block

Compressive strength

[7.3 N/mm²]
[10.4 N/mm²]


[100 mm]
[140 mm]


Close-textured finish available for decorative, fair-faced applications.
Provides an excellent surface for mortars, renders and plasters.

Manufacturer details

Bridge Road,
North Yorkshire, DL10 7HW
Tel +44 (0)1748 810204
Fax +44 (0)1748 813950
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