Ventform provides an excellent passive gas venting medium under suitably reinforced concrete ground floor slabs. When used in combination with perimeter vents and a suitable gas membrane it creates a highly effective method of protecting structures against the ingress of harmful ground gases.


  • Highly effective venting medium suitable for ground gas affected sites as part of a gas protection system
  • Provides a high degree of insulation and is manufactured from EPS which achieves a BREEAM rating of A+
  • Range of thicknesses and grades to suit most project requirements
  • Light, robust and easy to install 1200mm x 1200mm panels
  • Ventform panels are resistant to UV light, water and are flame retardant. They contain no CFC’s or HCFC’s

In addition to passive gas venting, Ventform panels also provide a high degree of insulation to the structure above. It is manufactured from expanded polystyrene (EPS) which achieves a BREEAM rating of A+.


Ventform panels are designed for use under suitably reinforced concrete slabs to form an insulated, passive gas venting layer.


The appropriate grade of Ventform panel should be selected based upon the required equivalent void and maximum load capacity that it is required to support. This information is provided in the table below:

Grades and Performance Characteristics

Ventform GradeOverall Depth
Leg Depth
Clear Void Equivalent
Maximum Load Capacity


Data Sheets

Product Issue Date Version Size Download
Ventform Data Sheet 09/2016 3 266.4 KB

MSDS Data Sheets

Product Issue Date Version Size Download
Expanded Polystyrene MSDS 10/2016 4 137.3 KB

Certification, Approval & Guidance


Product Issue Date Version Size Download
VOC & Ground Gas Solutions 10/2015 2 3.7 MB

NBS Clauses

Our NBS Clauses are hosted on the external website - view NBS Clauses

BIM Library

Please select the BIM file in the format you require.

Name IFC Size IFC Download Revit Size Revit Download
Ventform 37.0 KB 1,000.0 KB

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Request A CPD

Cordek offers a comprehensive Continual Professional Development (CPD) Seminar for engineers and architects. Our technical experts are happy to visit you at your convenience to hold a CPD session.

The presentation lasts approximately 45 minutes, with additional time for questions, and covers the following topics:

  • Ground Heave Solutions
  • VOC & Ground Gas Protection
  • Structural Fill Solutions

If you would like to request a CPD then please fill out the form below or give us a call.

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