Patent ID: 8689491
Filing Date: 2014-04-08
Classification: E04D

Abstract:
1. In combination with a heat weldable, thermoplastic roof covering affixed to a generally flat roof, the roof having a roof deck which supports the roof covering and at least one layer of roofing material which is disposed adjacent to the roof covering and which underlies it, said layer defining at least one naturally-occurring recessed area, the roof covering extending downwardly and inwardly from the recessed area's edges to form an upwardly-facing cavity, the improvement which comprises: (a) an air impermeable, sheet-like membrane and a charging valve mounted thereon and joined thereto so as to form a first airtight seal, the first airtight seal being disposed about the valve and between the valve and the membrane; (b) portions of the membrane which overlap the recessed area's edges being heat welded to the thermoplastic roof covering in such a way as to form a second airtight seal, the second airtight seal being disposed outwardly of the recessed area and extending in a continuous loop around the recessed area's perimeter; (c) the membrane with the charging valve so joined thereto and the roof covering, when the membrane is so heat welded thereto, defining an airtight member bounded by the second airtight seal; and (d) means, including the charging valve which, in use, fluidly communicates with the airtight member, for inflating the airtight member; the membrane, when the airtight member is sufficiently inflated, protruding generally upwardly so as to form a substantial bulge which spans that part of the roof covering which forms the upwardly-facing cavity as well as portions of the roof covering which, while they are situated outwardly from the recessed area's edges, are disposed inwardly of the second airtight seal, so that storm water which would otherwise pool in the upwardly-facing cavity is directed away from it.