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A guide to Midi concrete blocks
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When selecting masonry products for modern construction projects, there is often a balance to strike between structural performance, practicality and site safety. As manual handling regulations and on-site efficiency continue to influence specification decisions, many contractors are looking for products that are easy to work with without compromising on strength or durability.
The Lignacrete Midi block was developed with this in mind. Part of our Lignacrete range, these Midi concrete blocks provide the performance associated with standard 440mm dense concrete blocks but in a reduced length, which results in a significant reduction in unit weight.
What is a Midi block?
A Midi block is a dense 140mm thick concrete block, which is 290mm in length. This results in a 33% saving in unit weight compared with conventional size dense blocks. The block height remains at 215mm, allowing coursing to be maintained when bonding into adjacent walls of bricks or other block types
Their compact format does not compromise performance, with qualities such as compressive strength, fire resistance and sound insulation being equivalent to conventional size dense blocks. Midi blocks are available in strengths ranging from 7.3N/mm² to 30N/mm², making them suitable for a wide range of structural applications.
What size are Midi blocks?
Lignacrete Midi concrete blocks are manufactured with a face size of 290mm x 215mm. The block thickness is 140mm.
The Midi format ensures the unit weight remains below the recommended limit of 20kg.
When to choose Midi concrete blocks over standard concrete blocks
Midi blocks are suitable for general purpose walling applications, as well as for use in more high-strength loadbearing walls. Specifiers can be assured of a good technical performance while meeting manual handling obligations.
Given the range of strengths available, Midi concrete blocks are suitable for a wide range of residential, commercial, education and infrastructure projects.
Lignacrete Midi blocks are available in both Standard and Paint Grade finishes. Standard blocks have an excellent surface that can be plastered, rendered, drylined or clad, while Paint Grade blocks provide a close-textured surface suitable for direct decoration.
These blocks have been used in a number of high-profile developments, including the BBC Music Studios at East Bank in London, demonstrating their suitability for technically demanding commercial projects.
Where can Midi blocks be used?
Lignacrete Midi blocks are suitable for a wide range of general-purpose internal and external wall applications above and below ground, including loadbearing walls.
Typical uses include:
- Inner leaves of external cavity walls
- Internal walls, including fire break walls
- Separating walls
- Walls below the damp-proof course
In addition to their structural capabilities, Midi concrete blocks also offer strong fire, acoustic and durability performance. They achieve a Class A1 reaction to fire rating, meaning they are completely non-combustible. Walls constructed using Lignacrete Midi blocks can also achieve sound reduction levels exceeding 50dB (Rw), depending on the finish applied.
The blocks are frost resistant in accordance with PD 6697 guidance, allowing them to be used in exposed and below-ground conditions. Read the Lignacrete Midi datasheet.
Why Midi blocks are easy to handle on site
One of the main advantages of Midi blocks is their suitability for single-person handling. Their reduced size and sub-20kg weight improve grip and ergonomics during lifting and laying.
This can help reduce fatigue over the course of a working day. Easier handling can also support productivity on site, enabling workers to maintain a steady pace of work.
Handling should be carried out in accordance with HSE guidance and the Manual Handling Regulations, with appropriate site-specific risk assessments in place.
Choosing the Lignacrete Midi concrete blocks
The Lignacrete Midi block gives the performance of a standard dense concrete block in a more manageable format. Manufactured under a BSI-certified Quality Management System compliant with BS EN 9001, the blocks are BSI Kitemarked and approved to BS EN 771-3.
Whether you are specifying for a commercial, residential or infrastructure project, Midi concrete blocks provide a practical solution where performance and efficiency matter.
To find out more, visit the Lignacrete Midi product page or contact the Lignacite team to discuss your project requirements.
