Molded stone architectural product having a foam core

Abstract

An architectural cast stone product for use in building construction has a unitary shell made of a molded cementitious material that partially surrounds and is affixed to a foam core. The architectural cast stone product has a mounting surface including an exposed surface of the foam core and an exposed surface of the shell. The architectural cast stone product is made by obtaining a front pattern having a desired surface configuration for the architectural cast stone product, obtaining a foam core, affixing the foam core to a backer, affixing the front pattern to the backer that together form a mold, pouring a cementitious material into the mold and into contact with the foam core, at least partially curing the cementitious material to form the architectural cast stone product, and removing the front pattern and backer from the architectural cast stone product. The architectural cast stone product may optionally be surface finished, such as by sanding or polishing, to yield a desired surface finish.

1 . An architectural cast stone product, comprising: 
 a lightweight foam core;    a single continuous cementitious shell comprised of a molded cementitious material and that partially surrounds the foam core, wherein the cementitious shell is affixed to the foam core; and    a mounting surface comprised of an exposed surface of the foam core and an end surface of the cementitious shell.    
   
   
       2 . An architectural cast stone product as in  claim 1 , wherein the exposed surface of the foam core is substantially flush with the end surface of the cementitious shell.  
   
   
       3 . An architectural cast stone product as in  claim 1 , wherein the foam core includes a recess adjacent to the exposed and wherein the cementitious shell comprises a wraparound extension that extends laterally along the mounting surface into the recess of the foam core.  
   
   
       4 . An architectural cast stone product as in  claim 3 , wherein the wraparound extension extends parallel to the exposed surface of the foam core and nonparallel to an adjoining surface of the cementitious shell.  
   
   
       5 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell comprises a projection which extends into the foam core so as to at least partially assist in affixing the cementitious shell to the foam core.  
   
   
       6 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell includes two transversely oriented sections that meet so as to have the appearance of a miter joint.  
   
   
       7 . An architectural cast stone product as in  claim 1 , wherein the foam core is comprised of expanded polystyrene.  
   
   
       8 . An architectural cast stone product as in  claim 1 , wherein the foam core has a density less than about 2.0 lbs/ft 3 .  
   
   
       9 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell has a thickness greater than about ¼ inch.  
   
   
       10 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell has a thickness in a range from about ¼ inch to about 1 inch.  
   
   
       11 . An architectural cast stone product as in  claim 1 , further comprising a front pattern surrounding an exposed outer surface portion of the cementitious shell.  
   
   
       12 . An architectural cast stone product as in  claim 11 , wherein the front pattern has a non-planar surface configuration with three-dimensional features corresponding to a shape of the exposed outer surface of the architectural cast stone product.  
   
   
       13 . An architectural cast stone product as in  claim 12 , wherein the front pattern is comprised of expanded polystyrene foam.  
   
   
       14 . An architectural cast stone product as in  claim 1 , the cementitious shell having a surface that is non-planar with three-dimensional features.  
   
   
       15 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell has a polished surface finish.  
   
   
       16 . An architectural cast stone product, comprising: 
 a lightweight foam core;    a single continuous cementitious shell comprised of a molded cementitious material and that partially surrounds the foam core, wherein the cementitious shell is affixed to the foam core and has an outer surface configuration that is non-planar with three-dimensional features; and    a mounting surface comprised of an exposed surface of the foam core and an end surface of the cementitious shell.    
   
   
       17 . An architectural cast stone product as in  claim 16 , wherein the exposed surface of the foam core is substantially flush with the end surface of the cementitious shell.  
   
   
       18 . An architectural cast stone product as in  claim 16 , wherein the foam core includes a recess adjacent to the exposed and wherein the cementitious shell comprises a wraparound extension that extends laterally along the mounting surface into the recess of the foam core.  
   
   
       19 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell has a polished surface finish.  
   
   
       20 . An architectural cast stone product, comprising: 
 a lightweight foam core;    a single continuous cementitious shell comprised of a molded cementitious material and that partially surrounds the foam core, wherein the cementitious shell is affixed to the foam core; and    a mounting surface comprised of an exposed surface of the foam core and an end surface of the cementitious shell, the end surface of the cementitious shell including a wraparound portion that extends laterally into a recessed portion of the foam backer.    
   
   
       21 . An architectural cast stone product as in  claim 20 , wherein the exposed surface of the foam core is substantially flush with the end surface of the cementitious shell.  
   
   
       22 . An architectural cast stone product as in  claim 1 , wherein the cementitious shell has a polished surface finish.  
   
   
       23 . An architectural cast stone product manufactured according to a method comprising: 
 obtaining a front pattern having a desired surface configuration for the architectural cast stone product;    obtaining a foam core;    affixing the foam core to a backer;    affixing the front pattern to the backer, wherein the front pattern and the backer together form a mold having a mold cavity between the foam core, front pattern and backer;    introducing a cementitious material into the mold cavity and into contact with the foam core;    partially curing the cementitious material to form the architectural cast stone product comprised of a cementitious shell at least partially surrounding the foam core;    removing the front pattern and backer from the architectural cast stone product while the cementitious material is only partially cured and before it is fully cured in a manner so that the foam core and cementitious shell remain attached together as the architectural cast stone product; and    polishing a surface of the cementitious material to yield an architectural cast stone product comprised of the cementitious shell affixed to the foam core and having a polished surface finish.    
   
   
       24 . An architectural cast stone product as in  claim 23 , wherein the polished surface finish of the architectural cast stone product is produced by polishing the cementitious material while only partially cured and before being fully cured.