Owens Corning's AtticMate® attic vent is a rigid polystyrene sheet shaped to create a ventilation path/ cavity between the insulation and the roof deck. AtticMate® attic vents help ensure that the insulation does not block the air flow path. Inadequate ventilation may lead to excess heat and moisture build-up in the attic or rafter cavity. These conditions can lead to the deterioration of the roofing materials and deck, insulation, structural framing members, or interior ceiling finishes.