Concrete Blocks
(4 Products)Concrete blocks provide structural stability, load-bearing capacity, and durability for masonry construction projects. Manufactured from high-density aggregates, this range delivers dependable compressive strength and acoustic performance suitable for internal load-bearing walls, cavity walls, and subterranean blockwork.
Understanding Concrete Blocks
Concrete blocks are fundamental masonry units formed from dense aggregates, cement, and water, designed to support significant vertical loads while offering robust acoustic and fire resistance.
The current range focuses strictly on dense concrete formulations, which are highly suited to heavy structural applications where mass and acoustic density are prioritised.
These robust masonry units form the structural backbone of numerous domestic and commercial builds, from straightforward internal partition walls to highly stressed retaining structures.
Compressive Strength Grades
The structural capacity of masonry units is denoted by their compressive strength rating. The dense blocks in this range operate at a standard 7.3N/mm² grade. This 7.3N strength provides sufficient structural integrity for standard domestic and commercial load-bearing walls, foundations, and robust internal partitions, ensuring compliance with general structural engineering requirements and Building Regulations.
Thermal Mass and Insulation Performance
Dense concrete blocks possess excellent thermal mass, allowing them to absorb, store, and slowly release heat. This helps regulate internal building temperatures by smoothing out diurnal temperature fluctuations. While dense blocks provide superior thermal mass and acoustic reduction, projects prioritising low U-values and high thermal insulation should consider aerated blocks, which contain trapped air pockets to resist heat transfer.
Comparison Against Bricks and Poured Concrete
When compared to traditional clay bricks, concrete blocks offer faster installation times due to their larger face size, reducing mortar consumption and labour costs per square metre. Against poured concrete, blockwork eliminates the need for complex temporary formwork and long curing times, offering immediate structural stability upon the mortar setting. While poured concrete excels in massive monolithic structures, blockwork provides superior flexibility for standard wall construction and straightforward on-site modifications.
Material Range
- Solid Dense Blocks: High-mass masonry units providing exceptional load-bearing performance and acoustic insulation, featuring solutions such as the 100mm solid dense 7.3N block and the thicker 140mm variant.
- Hollow Dense Blocks: Structural units designed with internal voids to reduce overall wall weight while allowing for vertical reinforcement, represented by the 215mm hollow dense block.
Performance Benefits
- High Compressive Strength: Delivers robust load-bearing capabilities suitable for multi-storey residential and commercial applications.
- Acoustic Insulation: High material density significantly reduces airborne sound transmission between structural partitions.
- Fire Resistance: Non-combustible aggregate composition provides excellent structural stability and integrity during fire exposure.
- Durability: Highly resistant to impact, frost, and general physical degradation in exposed or subterranean environments.
Typical Applications
- Inner Leaves of Cavity Walls: Providing the primary structural support and thermal mass in traditional masonry cavity construction.
- Internal Load-Bearing Partitions: Separating spaces while supporting structural floor and roof loads from above.
- Foundation Walls: Creating robust substructure masonry below the damp-proof course.
- Retaining Walls: Utilising the hollow variants, often filled with concrete and steel, to hold back earth or heavy landscape materials.
Specification & Standards
- BS EN 771-3: Specification for masonry units. Aggregate concrete masonry units (Dense and lightweight aggregates).
- BS EN 1996-1-1 (Eurocode 6): Design of masonry structures. General rules for reinforced and unreinforced masonry structures.
Related Materials and Construction Uses
Concrete blocks form the core of structural masonry and integrate directly with other load-bearing components. Above wall openings, blockwork functions in tandem with concrete lintels to bridge gaps, while padstones are laid within the dense block courses to disperse heavy point loads from structural steelwork safely.
For horizontal spanning, dense block walls provide the necessary bearing capacity to support block and beam flooring systems.
When dealing with lateral soil pressure in retaining walls, the 215mm hollow blocks are often constructed with internal steel reinforcement before the voids are filled with concrete, delivering exceptional shear and tensile resistance.
Frequently Asked Concrete Blocks Questions
What's Stronger: Blocks or Bricks?
Bricks supersede blocks in terms of their compressive strength. However, their actual overall strength is largely influenced by the accompanying mortar used to assemble them.
What Does 'N' Mean in Concrete Blocks?
The compressive strength of each block is expressed in Newtons (N). For instance, the 7.3 N blocks that we sell have a characteristic compressive strength of 7.3 N per square millimetre (N/mm2).
How Are Concrete Blocks Manufactured?
Concrete blocks are typically manufactured in a block-making machine. Dry mixtures of cement, aggregates, and water are fed into moulds, compacted under high pressure, and then vibrated to ensure density and uniformity.
The blocks are then cured, often in kilns or by steam, to achieve their final strength.
Can Concrete Blocks Be Rendered Or Cladded?
Absolutely. Concrete blocks provide an excellent substrate for a variety of finishes.
They can be rendered with cementitious or acrylic renders, plastered internally, or cladded with materials such as timber, composite panels, brick slips, or stone.
What Are The Considerations For Storing And Handling Concrete Blocks On Site?
When storing concrete blocks on site, they should be kept on a flat, stable, and well-drained surface, preferably on pallets, to prevent them from absorbing ground moisture and to allow for easy access.
They should also be covered to protect them from rain, which can affect their moisture content and workability with mortar. When handling, mechanical aids like forklifts are preferred due to their weight, but if manually handled, sufficient lifting techniques should be used to prevent injury.
What Is The Life Span of Aggregate Blockwork?
When built correctly, masonry walls require minimal maintenance in comparison to other wall systems. Aggregate concrete blocks remain strong for years; the service life of masonry can be more than a century.
However, necessary maintenance may include replacing sealant at movement joints and junctions/openings as well as repointing external walls.
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