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ThermalStar® Flute Fill Roof Insulation

Flute fill insulation is a vital component of a building’s envelope. For building designers requiring the highest quality rigid insulation, ThermalStar® Flute Fill Insulation is a premium grade insulation manufactured to provide architects, specifiers, distributors, and contractors all the features and benefits inherent in a high-quality architectural insulation. ThermalStar Flute Fill Roof Insulation acts as the void filler and is designed to be installed over existing metal roofs. It provides a uniform and level substrate and is installed prior to the new roof system, providing a stable long-term R-value that will last the lifetime of your structure.

Manufactured under an industry-leading quality control program monitored by UL and ICC-ES, ThermalStar Flute Fill Insulation meets or exceeds ASTM C578 standards, providing an HFC free, recyclable rigid insulation with a low Global Warming Potential (GWP).


  • Custom cut to match the profile of the metal flutes, making installation quick and easy
  • Multiple thicknesses and compressive strengths available
  • Minimal long-term moisture retention with the ability to dry quickly
  • Stable, long term R-value to protect your structure for years to come
  • Environmentally friendly with a low global warming potential and zero ozone depletion potential
  • Limited lifetime warranty for physical and thermal performance