Patent ID: 6877288

Claim:
A waterproof-sheet type of roofing shingle comprising: an exposed surface portion and an overlap portion on which an adjacent roofing shingle is superimposed and adhered by adhesive, a waterproof sheet of the shingle being attached directly on a roof substrate to form a waterproof layer on a roof, the exposed surface portion having a rectangular configuration, the overlap portion being a margin of each of the shingles which extend along two sides of the exposed surface portion, and wherein a pressure of vapor or steam generated from the roof substrate beneath the waterproof layer may cause the waterproof layer to be expanded or bulged and further comprising: a plurality of belt tapes attached to a bottom side of the roofing shingle facing the roof substrate, the tape having air passage means for reducing the pressure of steam or vapor, the air passage means being in communication with the air passage means of the adjacent roofing shingle, whereby said air passage means is eventually in communication with an ambient atmosphere so as to vent said steam or vapor leaving the roof substrate to the atmosphere for preventing leakage of rain and bulging of the waterproof layer, wherein said air passage means has air passages formed by projections or grooves provided on said tape, the tape is provided with an extension extending outwardly from an edge of the roofing shingle, and the extension overlaps with the tape of the adjacent roofing shingle so that the air passage means is in communication with the air passage means of the adjacent roofing shingle, whereby expansion air between the roof substrate and the roofing shingles externally escapes through the air passage means to the atmosphere, when the roof is subjected to solar heat.