Lightweight Chimney Crown

Abstract

The present invention provides an exemplary lightweight chimney crown to protect a chimney from moisture and other elements. The chimney crown being comprised of a lightweight structural foam body with a cementitious coating covering the upper, inner, outer surfaces of the chimney crown body and preferably also covering the lower surface of the chimney crown body.

We claim: 
     
         1 . A lightweight chimney crown to be placed upon a chimney comprising
 a body and a coating, wherein   the body further comprises an upper surface, a lower surface, an inner surface, and   an outer surface wherein the lower surface has a drip slot and the coating covers the body upper surface, outer surface, and inner surface.   
     
     
         2 . The chimney crown of  claim 1  wherein the body is comprised of structural foam such as an expanded polystyrene (EPS) foam, an extruded polystyrene (XPS) foam, or the like and the coating is comprised of a structural coating. 
     
     
         3 . The chimney crown of  claim 2  wherein the body upper surface has a slope of at least about 10 degrees and the body thickness at the outer surface is about 2 inches and the drip slot is about ¼ inch deep and about ¼ inch wide. 
     
     
         4 . The chimney crown of  claim 3  wherein the drip slot is at least about 1½ inches away from the chimney outer wall. 
     
     
         5 . The chimney crown of  claim 4  wherein the structural coating is a cementitious coating. 
     
     
         6 . The chimney crown of  claim 5  wherein the cementitious coating comprises a scratch coat, a mesh, and an outer coating wherein the scratch coat is covered with the mesh and the mesh is covered with the outer coating. 
     
     
         7 . The chimney crown of  claim 6  wherein the chimney crown is attached to the chimney with a masonry adhesive. 
     
     
         8 . The chimney crown of  claim 7  wherein the masonry adhesive is a polyurethane based adhesive or a silicone based adhesive. 
     
     
         9 . The chimney crown of  claim 8  wherein the space between the chimney crown and the chimney is filled with a thermally resistant material. 
     
     
         10 . The chimney crown of  claim 9  wherein the thermally resistant material is fiberglass. 
     
     
         11 . The chimney crown of  claim 10  wherein the thermally resistant material is covered with a masonry caulk. 
     
     
         12 . The chimney crown of  claim 11  wherein the masonry caulk is a high temperature epoxy caulk. 
     
     
         13 . A lightweight chimney crown comprising
 a body and a coating, wherein   the body further comprises an upper surface, a lower surface, an inner surface, and   an outer surface wherein the lower surface has a drip slot and the coating covers the body upper surface, outer surface, and inner surface wherein the outer surface has an outward pitch from the upper surface towards the lower surface.   
     
     
         14 . The chimney crown of  claim 13  wherein body comprises a width and a length and the outward pitch is such that the width and length of lower surface are each about ½ inch greater than the width and length of the upper surface. 
     
     
         15 . The chimney crown of  claim 14  wherein the body is comprised of structural foam such as an expanded polystyrene (EPS) foam, an extruded polystyrene (XPS) foam, or the like and the coating is comprised of a cementitious coating. 
     
     
         16 . The chimney crown of  claim 15  wherein the body upper surface has a slope of at least about 10 degrees and the body thickness at the outer surface is about 2 inches and the drip slot is about ¼ inch deep and about ¼ inch wide. 
     
     
         17 . A lightweight chimney crown to be placed upon a chimney comprising
 a body and a coating, wherein   the body further comprises multiple sections each with an upper surface, a lower surface, an inner surface, and an outer surface wherein the lower surface has a drip slot and the coating is a structural coating which covers the body upper surface, outer surface, and inner surface.   
     
     
         18 . The lightweight chimney crown of  claim 17  wherein each body section is attached to an adjacent body section via glue, dowel and glue, dovetail grooves cut into the adjacent sections of structural foam and the like. 
     
     
         19 . The chimney crown of  claim 18  wherein the body upper surface has a slope of at least about 10 degrees and the body thickness at the outer surface is about 2 inches and the drip slot is about ¼ inch deep and about ¼ inch wide. 
     
     
         20 . The chimney crown of  claim 19  wherein the chimney crown is attached to the chimney with a masonry adhesive and wherein the space between the chimney crown and the chimney is filled with a thermally resistant material wherein further the thermally resistant material is covered with a masonry caulk.