Cover boards are thin substrates, which can be made from a variety of materials, that are installed between the insulation and membrane layers on a roof system.
Initially introduced to commercial roof systems to serve as a barrier preventing hot asphalt or solvent-based adhesives from damaging the insulation underneath, roof cover boards were also used to avoid blisters from forming in the system from insulation off-gassing when it came into contact with these adhesives.
Since then, cover boards have been commonly used to add durability to roof systems and have become a widely accepted roof component that adds a variety of attributes to commercial roof design.