Duo™ Interlocking Concrete Blocks

Elite Precast Concrete are the sole UK manufacturer of Duo™ interlocking concrete blocks. The blocks offer a robust, simple and flexible solution for constructing retaining walls, storage bays and segregation walls for a diverse range of materials.

Duo blocks are suited for:

• Retaining walls
• Pendine walls
• Salt bays
• Aggregate storage
• Compost, grain or wood chip material segregation walls
• Light scrap metals, white goods, RDF waste, black bag waste bay walls
• Temporary works
• Above ground/no-dig fencing and hoarding systems
• Fire resistant walls

Before you start your project, we would recommend that you check our stability and loadings directory where can find lots of information on wall heights, material storage and ground bearing/foundations.

External storage bays built using our interlocking blocks are deemed as a temporary structure, and typically do not require planning consent to erect, as they are easy to dismantle and relocate as needed, although we recommend that you should always check with your local authority first.

Installing a temporary structure rather than a permanent one, can result in lower or zero business rates and are generally cheaper to build.

We also have useful downloads available to assist you in the design of stockbay walls and inspecting existing walls.

Key features

• Durability and Fire Resistance: Duo blocks create incredibly durable and fire-resistant walls
• Easy Installation: The blocks are designed for quick and easy installation, featuring a clever design with a cast-in lifting pin flush with the concrete surface.
• Flexibility: Duo blocks can be dry laid onto any firm surface, allowing for bespoke bay dimensions to suit various site requirements.
• Reusability: As a semi-permanent option, these blocks can be easily reconfigured or relocated without the need for expensive, specialist lifting equipment.

Block specifications

The Duo interlocking block range includes three sizes:

• One connector
• Two connector
• Three connector

The standard block (BL2) measures 1200mm x 600mm x 450mm and weighs 750kg.

Compliance and Services

Duo interlocking concrete blocks comply with BS EN 1992-1-1:2004 – Design of concrete structures.

As leading manufacturers of precast concrete blocks, we can provide design and installation guidance. Additionally, structural and foundation design reviews are available upon request.

1. These loading figures are for guidance only – if in doubt consult a structural engineer.
2 The retained material should be allowed to naturally fall against the wall as it is stacked.
3 These loading tables relate to specific materials with a typical density and angle of repose, stacked to specific heights and slopes.
4 The client should ensure that the walls are built on a suitable base.
5 The density and angle of repose of each material shown are typical values only.

Further Duo™ block example calculations can be viewed in our Stability & Loading Calculations Directory.

For more information call 01952 588 885

Important note – prior to lifting older / pre-used blocks check the lifting pin for wear / corrosion and check the block for cracks. If the block is cracked or the pin is worn it could fail when being lifted.

Additional Notes – wind loading can affect the stability of single skin, stand-alone Duo block walls above 4.05m high. If in doubt get it checked by a qualified structural engineer. Direct impact between mobile plant and the block walls is unnecessary and should be avoided as in extreme cases this could dislodge blocks from the wall. If you identify a particular risk then strapping the top layers can help to mitigate the risk (see image below).

Legato blocks – top layers strapped

Please note that the concrete finish of our interlocking blocks is class as basic in accordance with the National Structural Concrete Specification for Building Construction. Under this specification there is no requirement other than the concrete being adequately compacted to achieve the density and compressive strength required.

Our Duo blocks have a moulded face and a trowelled face, where the appearance may be of concern, the moulded face tends to offer a smoother and more consistent look.

If you or your client would like a decorative finish, please visit www.eliteprecast.co.uk/concrete-walling-products.

Please note that blocks can be damaged if impact occurs during construction, and we cannot be held responsible for damage caused after the blocks have been delivered and signed for.

Important note: It is the customer’s responsibility to ensure appropriate structural checks are carried out before any precast concrete products are installed.