Concrete Blocks
(4 Products)Concrete blocks serve as the skeletal backbone of most structures we see in today's urban landscape. We stock a range of dense concrete blocks that offer impressive acoustic properties, as well as enhanced fire and water resistance. Formed by aggregate, these blocks' high-strength composition renders them suitable for load-bearing walls and a host of construction projects.
What Are Concrete Blocks?
Concrete blocks, more technically referred to as concrete masonry units (CMU) are a prime building material in wall construction.
Factory-produced under tightly controlled conditions, CMUs meet the dimensional and strength requirements of standards such as BS EN 771-3 (UK), ensuring predictable load-bearing capacity and code compliance on every project.
Concrete masonry is significantly quicker to apply than brick masonry - due to the fact that concrete blocks are a lot larger and cover a greater area with less labour.
Utilising concrete blocks also eradicates the complications that come with using timber as a primary framing material - you won't need to worry about wood warping and termite attack, for example.
Applications
- Internal load-bearing walls
- Beam and block flooring
- Cavity or solid wall constructions
- Walls, floors, and foundations
Benefits of Building with Concrete Blocks
- Durability & Longevity: CMUs are inherently robust, offering superior resistance to rot, pests, and decay. They provide a long-lasting, low-maintenance structural solution designed for the lifetime of a building.
- High Compressive Strength: Dense concrete blocks are renowned for their impressive load-bearing capabilities, making them ideal for foundations, multi-storey buildings, and structures requiring significant vertical support.
- Speed of Construction: Due to their larger size compared to traditional bricks, concrete blocks cover a greater area per unit. This translates to significantly quicker application and reduced labour time on site, accelerating project completion.
- Fire Resistance: As non-combustible materials, concrete blocks offer excellent fire protection. They do not contribute to flame spread and can withstand high temperatures for extended periods, enhancing building safety.
- Acoustic Performance: The mass of concrete blocks, especially dense varieties or those used in cavity constructions, provides excellent sound insulation, effectively reducing noise transmission between rooms or from external environments.
- Thermal Mass: Concrete blocks possess high thermal mass, meaning they can absorb, store, and slowly release heat. This property helps to moderate indoor temperatures, keeping interiors cooler in summer and warmer in winter, which contributes to energy efficiency.
- Versatility of Finish: Concrete blocks provide an excellent, stable substrate for a wide variety of finishes, including rendering (cementitious or acrylic), plastering internally, painting, or cladding with timber, composite panels, brick slips, or stone.
- Resistance to Pests & Warping: Unlike timber, concrete blocks are impervious to termite attack, woodworm, and issues like warping, cracking, or rotting, ensuring structural integrity without these common timber-related concerns.
Concrete Blocks Available
We offer a host of high-quality concrete blocks offering excellent thermal, acoustic and load-bearing performance. These include:
- Hollow Blocks - Breeze blocks and cinder blocks use significantly less concrete than dense concrete blocks and therefore reduce material cost in construction. They also bring down the overall weight of the structure while enhancing noise and thermal insulation.
- Dense Concrete Blocks - Dense concrete block is purposed for structural purposes such as load-bearing walls.
Working With Concrete Blocks
- Mortar Selection: The correct mortar mix is crucial for strength and durability. Typically, a cement-lime-sand mix is used, with ratios varying based on the block type and application (e.g., load-bearing vs. non-load-bearing). Always consult manufacturer guidelines and relevant building codes.
- Cutting Blocks: While robust, concrete blocks can be cut to size using specialist power tools like angle grinders with diamond blades, block saws, or hydraulic block splitters. Always use appropriate personal protective equipment (PPE).
- Reinforcement: For certain applications, such as retaining walls, tall walls, or structures in seismic zones, steel reinforcement bars (rebar) may be inserted into the block cavities and filled with grout to enhance tensile strength and stability.
- Weather Protection: While durable, exposed concrete block walls should be rendered, cladded, or painted for aesthetic purposes and added long-term weather protection.
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.
