90mm Cellcore HX S Under Slab (EPS) Anti Heave Board is purpose-built for placement beneath reinforced concrete floor slabs, delivering dependable protection against ground heave damage. This 90mm cordek hxs board features a cellular construction from Expanded Polystyrene, carefully engineered, formed, and tested to deliver consistent performance.
Brand: Cordek®
Model: 90mm (Grade 9/13)
Thickness: 90mm
Length: 2400mm
Width: 1200mm
Coverage: 2.88m2
Grade: 9/13
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: 300mm
Safe load: 9 kN/m2
Shrinkage Category: Low
Plasticity Index: 10-20
Fail load: 13 kN/m2
Features: Durable ǀ 4th Generation ǀ minimize wastage
Manufacturer: 90mm Cordek Cellcore HXS®
This anti-heave solution functions as a protective barrier beneath reinforced concrete floor insulation slabs, reducing ground heave effects by limiting the transfer of upward forces through the structure.
The 90mm Cordek Cellcore HXS Grade 9/13 board has been engineered and tested for concrete depths up to 300mm, guaranteeing reliable performance under specified conditions.
Our standard range includes various depths and grades suited to typical soil heave conditions and concrete thickness combinations. Specialist variants are available for pile caps, ground beams, or applications requiring integrated insulation, permanent formwork, or gas venting systems.
The 90mm Cellcore HX S range protects reinforced concrete floor slabs from upward forces caused by ground heave effects.

For concrete thicknesses between 1220mm and 2000mm, further grades of Cellcore are available. For further advice please contact the InsulationBee Technical Team on 02038839057 / 02038839057.
Each 90mm Cellcore hxs grade is calibrated to support a specific concrete thickness, plus an allowance for live loads of 1.5 kN/m², whilst maintaining minimal creep compression over a 16-hour curing period. This is defined as the "SAFE LOAD."
When the predetermined load limit is reached, the polystyrene legs of the 90mm Cordek panels will buckle and fail as underlying ground movement occurs, referred to as the "FAIL LOAD."
During design, ensure the slab, beam, or pile cap is sized to handle the difference between its weight and the fail load, as shown in the design examples provided.
Browse our Cordek selection and filter by thickness or coverage on the left side. For product suitability advice or bulk quotations, contact us on +4402038839057, email sales@insulationbee, or use Live Chat - Lowest UK Insulation board Prices.










