Fi-Foil’s Silver Shield^™ is an insulating product composed of multiple layers of low emittance (low-e) materials designed to significantly reduce radiant heat transfer. The inside layer is a metalized polymer. The outside layer is reinforced aluminum foil kraft paper bonded with a fire retardant adhesive. The layers expand when installed to form a reflective air space to provide enhanced thermal performance and protect the low emittance surface from the performance reducing effects of dust accumulation. Since metalized and foil-based aluminum products have a near zero water vapor permeance, Silver Shield^™ is perforated to allow water vapor transmission. Product applications include roofs and walls.