Insofast ISF18 for fixing flat roof insulation

Fixing flat roof insulation is quick and easy with Insofast ISF18 fixings. These one-piece hammer-in fixings are part of a range of insulation anchors manufactured by Thor Helical. The fasteners have a twin-start spiral shank welded to a button head and are designed to secure plywood topped composite insulation boards to timber roofing rafters.

Composite insulation panels are insulation and decking in one; a layer of rigid insulation laminated to a thin sheet of exterior grade plywood or OSB. They are ideal for constructing insulated flat roof decks on small building structures such as home extensions and garages. This type of construction places the insulation above the roof rafters to create a warm roof construction, reducing the risk of condensation within the roof and eliminating the need for ventilation beneath the deck.

Thor Helical supplies Insofast ISF18 fasteners in stainless steel and galvanised steel versions. The helical nails offer a rapid and reliable method of fixing flat roof insulation boards in warm roof deck applications. Unlike traditional screws and nails, they cannot be over-driven and cannot compress the insulation. When hammered-in, the fixings corkscrew through the insulation and into softwood rafters until the button-head indents into the plywood to clamp the panel securely in place.

What makes the Insofast ISF18 a cut above the rest?

  • Galvanised ISF18 (CSA of 10mm2) is 25% less conductive than the 8mm Suretwist (13.5mm2)
  • Also available in stainless steel for added corrosion protection and a further 30% reduction in thermal conductivity.
  • Complies with Euro-Code 5 Table 8.2 for edge distance; 5 x diameter (by area)
  • 18mm diameter dome reinforced head eliminates sharp lifting edges
  • Quick and easy to use
  • Corkscrew action alleviates splitting of joists or rafters