Layered roofing shingle with dead-air space

Claim 1

A generally rectangular roofing shingle adapted to be applied to a sloping roof so as to have upper and lower edges transverse to the slope of the roof and side edges parallel to said slope, said shingle comprising: a. an outer layer of flexible material, b. an inner layer of flexible material, c. an intermediate layer providing an air space between outer and inner layers, said intermediate layer comprising a series of generally parallel tubular members extending at right angles to the upper and lower edges of the shingle, each of said tubular members opening through the lower edge of said shingle and terminating in spaced relation below the upper edge of the shingle, and a spacer strip of solid, flexible material disposed between said outer and inner layers between the upper ends of said tubular members and the upper edge of said shingle, said spacer strip being spaced apart from the upper ends of said tubular members whereby to form an air passage interconnecting all of said tubular members at their upper ends, and means sealing the ends of said air passage at the respective side edges of said shingle, and d. means bonding said outer, inner and intermediate layers together to form a unitary structure, said shingle being adapted to be secured to a roof structure adjacent its upper edge, whereby said elongated tubular members of said intermediate layer serve to stiffen said shingle against flexure normally to its plane about any axis parallel to its upper and lower edges.