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Method of application

Before insulation is placed on the roof deck, the substrate must be clean, dry, free of debris, water, ice or snow and suitably prepared by removing all defects that might affect the quality of the application. Any unusual deck conditions or defects should be brought to the architect or building owner’s attention prior to installation.

RESISTA AK insulation boards must be installed using plates and fasteners or Firestone-approved insulation adhesives. Insulation shall be neatly fitted to all roof perimeters, penetrations and abutments. Do not install more insulation boards than those that can be covered with membrane and completed before the end of each day’s work or before the onset of inclement weather. Make sure boards are installed with marking “This side down” in case of a fully adhered membrane application. 

  • Mechanically Attached Single-Ply Systems: fasten the insulation boards with a minimum of: ​Additional fasteners may be required in areas of high wind loads or around the perime­ter of the roof.
    Please refer to local wind uplift requirements and/or contact Firestone’s Technical Department.
    • 4 approved fasteners and plates per 600 x 1200 mm board
    • 4 approved fasteners and plates per 1200 x 1200 mm board
    • 6 approved fasteners and plates per 1200 x 2400 mm board.
  • Ballasted Single-Ply Systems: insulation boards may be loose laid. If mechanical attachment is specified, please contact Firestone’s Technical Department.
  • Fully Adhered Single-Ply Systems: the number of fasteners per board needs to be determined based on a wind uplift calculation in accordance with local building regulations and taking into account the following minimum requi­rements


Thickness 600 mm x 1200 mm board 1200 mm x 1200 mm board 1200 mm x 2400 mm board
30 mm min. 4 fasteners/board min. 8 fasteners/board min. 16 fasteners/board
50 mm min. 4 fasteners/board min. 6 fasteners/board min. 12 fasteners/board
>50 mm min. 4 fasteners/board min. 5 fasteners/board min. 8 fasteners/board