Patent ID: 8215339
Filing Date: 2012-07-10
Classification: E04B,E04F,Y10T

Abstract:
1. A vapor barrier for sealing an interior of a building from an insulation cavity defined by structural members of the building, the vapor barrier comprising: a flexible and substantially impermeable sheet having apertures to allow air to exit the insulation cavity during filling of the insulation cavity with loose fill insulation; and one-way valves mounted across the apertures, the valves configured to allow air flow out of the insulation cavity and into the building interior through the apertures and to substantially prevent air flow from the building interior into the insulation cavity, wherein the flapper valves have the structure of flexible and frameless valve sheets configured to extend from a respective base end fixed to the impermeable sheet to a respective distal end, wherein the valve sheets are movable between a first position and a second position, wherein in a first position, the base ends and the distal ends of the valve sheets overlap portions of the impermeable sheet and are in contact with the impermeable sheet, and in a second position, the distal ends of the valve sheets are spaced from the impermeable sheet.