Question 1

What are lightweight concrete blocks typically used for?

Accepted Answer

Lightweight concrete blocks serve a multitude of construction needs, primarily forming internal walls and partitions within diverse building types. Their thermal efficiency also makes them a popular choice for the inner leaf of external cavity walls, aiding in insulation. Higher-strength varieties see use in load-bearing walls for lower structures, while their acoustic properties are valued in party wall construction. Additionally, they function as infill within beam and block flooring systems and, with appropriate damp-proofing, can be utilised in certain below-ground wall applications. Their inherent fire resistance further contributes to their widespread use in creating compliant and safe buildings throughout the UK.

Question 2

What is the difference between lightweight concrete blocks and standard concrete blocks?

Accepted Answer

The primary difference between lightweight and standard concrete blocks lies in their density and composition. Standard concrete blocks utilise dense aggregates like crushed rock or gravel, resulting in a heavier, more robust unit with higher compressive strength, typically favoured for substantial load-bearing applications.

Conversely, lightweight concrete blocks incorporate lighter aggregates, such as expanded clay, shale, or slag, or are aerated through a chemical process, yielding a significantly less dense block. This reduced density translates to easier handling, improved thermal insulation – a crucial factor for UK energy efficiency regulations – and often better acoustic performance compared to their standard counterparts.

While standard blocks excel in high-load scenarios, lightweight blocks are preferred for their thermal properties and ease of use in walls, partitions, and certain load-bearing situations where weight is a consideration.

Question 3

Are "Lightweight Breeze Blocks" the same as Lightweight Concrete Blocks?

Accepted Answer

The term "breeze block" is often used interchangeably with "lightweight concrete block," but there's a nuance rooted in historical composition. Traditionally, "breeze blocks" were made using cinder ash (breeze) as a lightweight aggregate. Modern "lightweight concrete blocks", while serving similar purposes, are manufactured with a broader range of lightweight aggregates like expanded clay, shale, or slag, or through aeration processes.

While the terms are often used synonymously in the UK for blocks that are lighter and easier to handle than dense concrete blocks, the original "breeze block" had a distinct composition. Today, most products marketed as "lightweight concrete blocks" achieve their reduced weight through various modern methods and aggregates, effectively encompassing the functional role the older "breeze block" once filled. So, while not strictly identical in historical makeup, they largely refer to the same category of lighter-density concrete blocks used for similar construction applications in the UK.

Lightweight concrete blocks

Thermalite Solid Hi-Strength Block 7.3N 100mm

Plasmor Fibolite Solid Lightweight Concrete Block 3.6N 100mm

Thermalite Hi-strength Block 7.3N 140mm

Forterra Fenlite Solid Lightweight Concrete Block 7.3N 100mm

Lightweight Solid 7.3N Block 440 X 215 X 140 mm

Thermalite 215mm Party Wall 4N 660kg/m3

Thermalite Solid Shield Block 3.6N 140mm

Plasmor Aglite Solid Block 4.2N 100mm

Lignacite Block 440mm X 215mm 3.6N 850kg/m3

Thomas Armstrong Solid Ultralite Concrete Block 3.6N 100mm

Plasmor Fibolite Solid Lightweight Concrete Block 7.3N 100mm

Thermalite Solid Shield Block 3.6N 50mm

CCP MODULITE SOLID LIGHTWEIGHT 100mm 7.3N 301410