225mm Cellcore HX S Under Slab (EPS) Anti Heave Board S is specifically engineered to be placed beneath reinforced concrete floor slabs, providing robust protection against the potential impacts of ground heave. This 225mm cordek hxs features a cellular structure made from Expanded Polystyrene, meticulously designed, molded, and rigorously tested to meet precise performance specifications.
Brand: Cordek®
Model: 225mm (Grade 24/32)
Thickness: 225mm
Length: 2400mm
Width: 1200mm
Coverage: 2.88m2
Grade: 24/32
Standard Panel: 2400mm x 1200mm
Beams Widths: 2400mm x 1200mm to 300mm (in 25mm increments)
Material: (EPS Insulation) Expanded Polystyrene
Shipping method: Rigid Vehicle ǀ Courier
Applications: Reinforced concrete floor slabs
BBA Certified: Yes
Maximum depth of concrete: 900mm
Safe load: 24 kN/m2
Shrinkage Category: Low
Plasticity Index: 40-60
Fail load: 32 kN/m2
Features: Durable ǀ 4th Generation ǀ minimize wastage
Manufacturer: 225mm Cordek Cellcore HXS®
The 225mm Cordek Cellcore HX S Under Slab 24/32 serves as a protective layer beneath reinforced concrete floor insulation slabs, mitigating the impact of ground heave by minimizing the transmission of upward forces to the structure.
The Anti Heave Board, specifically the 225mm Cordek Cellcore HXS in Grade 24/32, is precisely engineered and calibrated for concrete thicknesses of up to 900mm, having undergone rigorous testing to ensure it consistently meets the specified performance criteria.
Our standard product line offers a diverse selection of depths and grades to accommodate the typical combinations of soil heave potential and concrete depth commonly encountered. Additionally, we offer product variations suitable for applications beneath pile caps and ground beams, or for situations requiring integrated insulation, permanent formwork, or passive gas venting solutions.
The 225mm Cellcore HX S range is designed to protect reinforced concrete floor slabs from the upward forces associated with the effects of ground heave.

For concrete thicknesses between 1220mm and 2000mm, further grades of Cellcore are available. For further advice please contact the InsulationStore Technical Team on 02039519012 / 02038839057.
Each 225mm Cellcore hxs grade is engineered to support a specific thickness of concrete, along with an additional allowance for live loads, equating to 1.5 kN/m², all while exhibiting minimal creep compression during a 16-hour curing period. This combination of factors is referred to as the "SAFE LOAD."
At the predetermined load threshold, the polystyrene legs of the 225mm Cordek panels will experience buckling and collapse due to the upward movement of the underlying ground, a scenario known as the "FAIL LOAD."
In the design process, it is imperative that the slab, beam, or pile cap is configured to accommodate the difference between its own weight and the fail load, as illustrated in the design examples on the following page.
Have a browse of our Cordek stock and filter by thickness or coverage on the left-hand side of the page. If you’d like to talk through the suitability of some products for your project, or get a quantity discount quotation please call us by phone on +4402039519012 , email sales@insulationstoreonline or Live Chat - Lowest UK Insulation board Prices.











