ISO – ISO (polyiso) is one of the most common form of commercial roof insulation. It consists of a closed-cell polyiso foam with black glass reinforced facer on most manufactures product. It is available, and in stock, in many different thicknesses. We also stock truckloads of tapered ISO for all tapered needs. Please review the manufactures below we carry at RSG. 
Roofing Insulation
Perlite – Perlite is a roof insulation typically used in Built-up or modified applications. It consists of perlite fibers, mineral aggregate and waterproofing agents. We stock all typical sizes including tapered and cant strips. Please review the manufactures below we carry at RSG.
EPS – EPS (Expanded polystyrene) is a roof insulation that is comparable, to an extent, with ISO(polyiso) single ply applications. EPS is a closed cell, lightweight formed plastic. It comes in any requested thickness and also comes in tapered sizes. Please review the following manufactures we carry at RSG.
Georgia Foam – www.georgia-foam.com
Insul-foam - http://www.premier-industries.com/insulfoam/
Extruded polystyrene – Extruded roof insulation is an excellent form of insulation for most systems. It is used most commonly in metal roof applications. It comes in various sizes and thicknesses. It is also available in tapered sections.
Fiberboard – Fiberboard is a roof insulation that is a great product for reproofing applications. It consists of mineral wood fibers and waterproofing agents. It is typically coated with asphalt on two sides for adhering ply products and waterproofing, but is also available in a six sided coating application. Please review the following manufactures of fiberboard we carry at RSG.
Continental –