As the wind picks up speed, the loose-laid, single-ply roof membrane reacts almost instantly, a subtle ripple coursing through the tough 60-mil sheet. As air is forced through the perimeter roof vents, the negative pressure kicks in, forcing the membrane tight against the insulation below. At the same time, the wet polyiso left in the existing roof system begins to dry out.
It’s the Negative Pressure Roofing System in action on another roof retrofit. Also referred to as a “wind-vented” roof, the design is protected by more than 25 patents and is proven in thousands of roof installations encompassing approximately 94 million square feet. Several well-respected roofing contractors and property owners in the Midwest swear by the system, with no history of failures among companies with more than 15 years of experience using the technology.