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  • Split textured or smooth faced retaining walls.
  • Marine walls.
  • Bridge abutments.


Dry laid, interlocking concrete blocks that simply lock into place to a preset face angle creating a simple dry-build solution to an engineering problem.


  • Split textured or smooth faced retaining walls.
  • Marine walls.
  • Bridge abutments.

General information

Uniclass 2015

Pr_20_93_71_15 Concrete interlocking blocksPrimary


D41/310 Drystack interlocking masonry

Specification data - Concrete interlocking blocks

Product Reference






Standard product features

Size (l x w x h):

200 x 1000 x 130.5 mm. Can be split to achieve 500 or 250 mm width walls.




To be determined by wall height and location but generally traditional concrete strip foundation.


Blocks manufactured from machine pressed and vibrated concrete based upon a 35n/mm² compressive strength mix.

Blocks are delivered to site in 1000 mm lengths where they are then split using pre-formed inducers to the required width of 250, 500 mm to achieve different wall thickness according to design. This process achieves a split stone finish that doesn’t suggest an artificial uniform moulding and enables natural flecks of aggregate to be shown.

The wall angle is set by locating male and female splines to the top and bottom of each unit. The achievable face angles from vertical are 2 to 6° by rotation of the first course and 15, 28 and 39° by offsetting the splined connections, with blocks laid plumb. As each course proceeds the wall is backfilled with a free draining low fines granular backfill.

Design may incorporate a structural backfill of pre-determined width, featuring Betonap geo-grid layers positioned horizontally across backfill and rear of block to form a composite mass wall.


Line retained face with a geo-textile and incorporate a perforated coil drain to the heel of the first course.

Product Options

Betonap in differing grades. Standard copings.

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