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Armstart Concrete Block

Foundation blocks available in a range of width and length combinations. Solid Armstart walls are safer, easier and more cost-effective then cavity walls.

Consists of up to 90% high quality recycled and reclaimed aggregates.


  • Solid foundation walls from 250–350 mm thick to suit cavity wall widths of 75–150 mm.
  • Simple and safe alternative to cavity foundation walls, no wall ties required, cavity filling or danger of collapsed cavities, faster build rates, less mortar and labour required.
  • Suitable for use in soil conditions up to DS-3 as defined in BRE Special Digest 1.
  • Range of strengths available to suit low rise and high rise buildings.
  • All blocks are below 20 kg and as such comply with HSE and CDM guidelines for single unit repetitive manual handling.

Manufactured to BS EN 771-3.

General information


300 x 250 mm

300 x 275 mm

320 x 280 mm

350 x 250 mm

Uniclass 2015

Pr_20_93_52_01 Aggregate concrete blocksPrimary


F10/355 Concrete common blockwork

F10/36 Concrete common blockwork

Specification data - Aggregate concrete blocks

Product Reference

Armstart Concrete Block


7.3 N/mm²

10.4 N/mm²


300 x 250 mm

300 x 275 mm

320 x 280 mm

350 x 250 mm

Standard product features

Dimensional tolerance:

Category D1.

Dry density:

1450–1550 kg/m³.

Thermal conductivity:

0.49 W/mK.

Fire resistance to BS EN 13501-1:

Class A1.

Configuration to BS EN 1996-1-1:

Solid, group 1.

Product Options

Compressive strength:

7.3 and 10.4 N/mm² available as standard, higher strengths are available to order.

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