Roof ventilator having fluid flow control and method of making same

A device for relieving positive air pressure within a roof of the type including a flexible, substantially air tight outer membrane, comprising:

• an upstanding, essentially hollow housing having an upper end spaced above said roof and a lower end secured to said roof, said upper end including an outlet opening through which air may escape from said housing into the surrounding atmosphere, said lower end including an inlet opening adapted to overlie an opening in said membrane whereby air under positive pressure within said roof may pass into said housing through said lower opening;
• a one way flap valve within said housing and shiftable from an open position for allowing air within said roof under positive pressure to flow upwardly through said housing to a closed position for preventing air flow downwardly through said housing into said roof;
• and,
• means for mounting said flap valve within said housing in spaced relationship to said inlet and outlet openings,
• said mounting means including a cylindrical insert receivable within one end of said housing and having a longitudinal air passage therethrough, said insert being mounted within said housing and tightly engaging the entire inside perimeter of said housing, whereby all the air passing through said housing flows through said air passage in said insert, said insert including first and second mating sections of structurally self-supporting foam material, said insert including a strut extending transversely across said air passage, said strut being defined by first and second portions disposed in face-to-face relationship to each other and respectively formed integral with said first and second insert sections, said flap valve being sandwiched between said first and second strut portions.

A device for relieving positive air pressure within a roof comprising:

• an upstanding, generally cylindrical tube having an upper end spaced above said roof and a lower end adapted to be secured to said roof, said upper end including an outlet through which air may escape from said tube into the ambient environment, said lower end including an inlet adapted to overlie an opening in said roof through which air under positive pressure may enter said inlet;
• and
• flow control means within said tube for controlling the flow of air through said tube, said flow control means including
• (1) a flexible valve member,
• (2) means for mounting said flexible valve member for flexing movement between an open position allowing air to flow from said inlet through said tube to said outlet, and a closed position preventing flow of fluid from said outlet through said tube to said inlet and into said roof, said mounting means including a sleeve received within and secured to said tube, said sleeve including first and second portions disposed in end-to-end, abutting relationship to each other, said valve member being sandwiched between said first and second sleeve portions.

A method of fabricating a roof ventilation device, comprising the steps of:

• (a) forming a tubular housing through which air may flow;
• (b) forming a first insert portion;
• (c) forming a second insert portion, said first and second insert portions having a passageway through which air may flow;
• (d) forming a substantially flat valve member configured to cover said passageway;
• (e) interposing said valve member in sandwiched relationship between said first and second insert portions;
• and,
• (f) inserting said first and second insert portions and said valve member in sandwiched relationship into said tubular housing.