Roof construction and method thereof

Abstract

A roof is prepared wherein the water barrier layer is placed on a roof deck and waterproof thermal insulation is placed over the water barrier layer. The water barrier layer is not subjected to the extremes of temperature that are encountered when the water barrier layer is the outermost element of the roof structure.

What is claimed is: 
     
       1. A method of preparing a built up roof consisting essentially of applying and affixing to a roof deck a water impermeable membrane disposing a plurality of closed cell water impermeable thermal insulating members .Iadd.in coplanar disposition .Iaddend.having fissures therebetween above said water impermeable membrane on the upper side of the membrane and applying a water permeable protective layer .[.on.]. .Iadd.consisting only of loose gravel spread directly over .Iaddend.the thermal insulating layer, .Iadd.the exposed face and body of said protective layer and the interface of said protective layer with said thermal insulating layer being water permeable. .Iaddend. .[.2. The method of claim 1, including the step of forming the water impermeable membrane from a plurality of layers of roofing felt and a bituminous adhesive..]. .[.3. The method of claim 1, including the step of adhering the insulating material to the water impermeable membrane..]. .[.4. The method of claim 1, wherein the 
     
     
        protective layer is an inorganic mortar..]. 5. A roof structure consisting essentially of a roof support means having a roof deck, the roof deck having an upper surface and a lower surface, the upper surface of the roof deck supporting a water impermeable membrane, the impermeable membrane having an upper face and a lower face being generally adjacent the roof deck, a thermal insulating layer disposed adjacent the upper face of the water impermeable membrane, the thermal insulating layer comprising a plurality of closed cell water impermeable insulating members .Iadd.disposed in coplanar disposition and the members defining fissures between adjacent members .Iaddend.and the members defining fissures between adjacent members and a water permeable protective layer .Iadd.consisting only of loose gravel spread directly over and .Iaddend.disposed on the surface of the insulating material remote from the roof deck, .Iadd.the exposed face and body of said protective layer and the interface of said protective layer with said thermal insulation 
     
     
        layer being water permeable. .Iaddend. .[.6.  The roof structure of claim 5, wherein the water impermeable layer comprises a plurality of layers of 
     
     
        bituminous adhesive and roofing felt..]. .[.7.  The roof of claim 5, wherein the insulating layer is a synthetic resinous closed cell foam..]. .[.8. The roof of claim 5, wherein the insulating material is adhered to the impermeable membrane..].