Technical info

Fully pre-fabricated panels

Our G21 Fire Panels are passive fire protection products, designed, manufactured and tested by InterDam BV. The fire sandwich panels are fully prefabricated and pre-coated wall systems, made from mineral wool sandwiched between two metal sheets and available in A60 or H120 fire ratings in accordance with IMO regulations. These H120 and A60 fire wall systems are even approved to resist jet fires.


G21 Fire Panels are delivered as ready-to-install panels, supplied with stainless steel self-tapping screws (and flashings to finish the walls upon request). Installation can easily be performed using standard tooling equipment – no hotwork or post-installation activities are required

Fully tested and certified

Our prefabricated panels have been extensively tested for fire resistance (for both wall and ceiling applications), airtightness and corrosion. Testing has even been performed with incorporated service penetrations such as pipes, cable transits and duct penetrations, resulting in a fully approved A60 wall system including penetrations. Relevant approval for every fire rating is available from DNV or Lloyd’s Register.

Exceptional protection

Mineral wool serves as the core material for the panel, which is standardly-provided with coil-coated HPS 200 mu mild steel skins (0.7 mm thickness). Our clients can also choose stainless steel 316 skins (2B finish or coil-coated 25 mu PVDF) as an option. The result is a heavy duty fire resistant panel that is also very light-weight, using the minimum amount of materials to provide exceptional protection. Our sandwich panels are assembled in a continuous production line – take a look at the video below to see the production process for yourself!

Fire resistant penetrations

The panels including pipe, HVAC and MCT penetrations have been physically fire tested. All penetration details are designed not to impose any loading to the wall panels during a fire. Penetrations can generally be located anywhere within the wall area, depending upon the span of the panels.

Suitable for a variety of projects

G21 Fire Panels can be used as internal or external fire walls, or as a suspended ceiling. The prefabricated fire panels are suitable for projects with fire resistance requirements, including:

  • Offshore wind substations
  • Prefabricated modules such as E-houses
  • Oil & Gas platforms/plants

Click here to see some of our recent G21 Fire Panel reference projects.

Other available options

  • Design and engineering support for your project from our experienced in-house engineering team
  • Cut-outs/penetrations for pipes, multi-cable transits (MCT) and HVAC ducts
  • Blast resistant or blast relief function of the panels
  • Integration of fire doors or windows
  • Packing and worldwide transport

sandwich panels