75mm Claymaster

75mm Claymaster is an EPS compressible-fill material that can be used to prevent potential foundation issues caused by moisture movement in soils containing a significant proportion of mineral particles below 0.002mm (clay heave). This material serves as permanent shuttering for cast in-situ reinforced concrete, reducing pressure on ground beams in piled foundations, and on the sides of trench fills.

Shrinkable clays are soils with a substantial proportion of mineral particles measuring less than 0.002mm in diameter. When wet, they form a highly cohesive soil type, which turns crumbly and crazed when dry. This expansion and contraction process, known as clay heave, can lead to severe foundation problems.

Claymaster is a specialised low-density expanded polystyrene material, coloured in pink for easy identification, and can be ordered in additional widths.

Application

The product is suitable for:

• Supporting concrete ground beams with a maximum depth of 600mm
• Piled foundation construction
• The vertical face of deep trench foundations

It helps reduce the pressure exerted on concrete by preventing the expansion of clay soils (clay heave) over the life of the structure.

Characteristics

• Claymaster offers a rapid and cost-effective solution to clay-heave problems, requiring no specialized trades or equipment
• For normal ground-beam depths up to 600mm, initial material compression during casting can be disregarded
• Claymaster is rot-proof, durable, and can withstand below-ground conditions. It remains unaffected by high levels of groundwater or precipitation
• Boards are typically rectangular and uniform in thickness, but special shapes can be ordered, including circular sections to fit around pile caps and tapered boards
• According to NHBC Standards, Chapter 4.2 for building near trees, low-density compressible polystyrene is a suitable proprietary material for mitigating ground pressures on foundations in shrinkable soils

Certification

Claymaster has been assessed by the British Board of Agrement according to Regulation A2. It has been found to reduce the effects of clay soil expansion, which could compromise the stability of a building. The material is approved for use under ground beams and against the sides of deep-trench fill foundations. Certificate number: 90/2543.

Please note this product is made to order; therefore, it is non-returnable.