Question 1

What are trench blocks used for in construction?

Accepted Answer

Trench blocks are essential components in construction, primarily utilised to create stable, reinforced, and insulated foundation bases. They are designed to fill and support foundation trenches, providing a solid, level footing that distributes structural loads evenly across the ground. These blocks are ideal for supporting load-bearing walls, retaining walls, and underground structures in both residential and commercial projects. Thanks to their durability, low water absorption, and insulation properties, trench blocks help improve energy efficiency, reduce heat loss, and enhance overall foundation stability. Their versatility and strength make them a popular choice for foundational work in diverse construction environments, from simple extensions to complex infrastructure projects.

Question 2

How much do trench blocks cost?

Accepted Answer

The price of trench blocks in the UK generally varies between £10 and £30 per block, depending on several key factors. The size of the trench block plays a significant role, with larger or higher-specification blocks such as 355mm or high-strength 7N variants tending to be at the higher end of the price range. Material quality also influences pricing; premium-grade concrete or specialty trench blocks with enhanced durability may cost more than standard options. Additionally, insulation features—such as those found in Thermalite trench blocks—can add to the cost due to their energy-efficient properties. Buying in bulk often reduces the overall cost per block, making large-scale projects more economical. When planning your budget, consider not only the initial purchase price but also the long-term benefits of choosing quality, insulated, or high-strength trench blocks suitable for demanding foundation work.

Trench blocks

Thermalite 300mm Trenchblock T&G 3.6N

Hi-strength Thermalite Trench Blocks 7.3N 300mm

Plasmor Fibolite Solid Block 7.3N 100mm (Southern)