Modular building construction system using light weight panels

Abstract

Light-weight modular panel systems including a plurality of panels formed of a cementitious material, with a fiber-reinforced shell layer and an adjacent substrate layer. The panels employ a light-weight aggregate that provides the panels with the ability to be cut, sanded, drilled, screwed, and otherwise shaped using common wood working tools. A dual panel thickness wall construction may be formed by using the panels to provide interior and exterior portions of a wall construction. Seams between adjoining panels may be spanned with fiberglass mesh and bonded with polymer modified cementitious adhesive, providing excellent strength in that the joints between adjacent modular panels do not represent a weak point of the wall construction. The resulting wall provides greater strength than the individual panels, and results in a monocoque structure in which interior and exterior panels, and their respective fiber reinforced layers are spaced apart from one another.

What is claimed is: 
     
         1 . A light-weight modular panel system comprising a plurality of light-weight modular panels to be attached to one another, each panel comprising:
 a cementitious material including a front surface, a back surface, and edge surfaces between the front and back surfaces, wherein the panel includes a cementitious shell layer and a cementitious substrate layer adjacent to one another,   the shell layer comprising a light-weight aggregate and reinforcing fibers dispersed and bonded in a cementitious matrix, the shell layer having a first aggregate to cement ratio;   the substrate layer comprising a light-weight aggregate dispersed and bonded in a cementitious matrix, the substrate layer being substantially void of reinforcing fibers, the substrate layer having a second aggregate to cement ratio that differs from the first aggregate to cement ratio of the shell layer;   wherein the light-weight aggregate has a density of not more than about 30 lbs/ft 3  and provides the resulting cementitious material of the panel with the ability to be cut, sanded, drilled, screwed, and shaped with common woodworking tools.   
     
     
         2 . A light-weight modular panel system as recited in  claim 1 , wherein each panel includes no cellulose based materials. 
     
     
         3 . A light-weight modular panel system as recited in  claim 1 , wherein each panel has a thickness from about 1.5 inches to about 2 inches and is sized to weigh no more than about 150 pounds so as to be easily manipulated by two workmen. 
     
     
         4 . A light-weight modular panel system as recited in  claim 1 , wherein the shell layer provides the front surface and the substrate layer provides the back surface, the front surface provided by the shell layer being a finished surface such that no additional surface finishing is required. 
     
     
         5 . A light-weight modular panel system as recited in  claim 1 , wherein the light-weight aggregate has a density from about 5 lbs/ft 3  to about 15 lbs/ft 3 . 
     
     
         6 . A light-weight modular panel system as recited in  claim 1 , wherein the light-weight aggregate is silica based and the cementitious material from which the panels are formed is substantially void of sand. 
     
     
         7 . A light-weight modular panel system as recited in  claim 1 , wherein a density of the panel is from about 50 lbs/ft 3  to about 65 lbs/ft 3 . 
     
     
         8 . A light-weight modular panel system as recited in  claim 1 , wherein at least one panel comprises a plurality of spaced apart slots formed the substrate layer to allow the panel to bend. 
     
     
         9 . A light-weight modular panel wall construction system comprising:
 an interior panel including an exposed interior surface, an opposite interfacing surface for interfacing with an exterior panel or a material sandwiched between the interior panel and an exterior panel when the panel system is assembled, and edge surfaces between the interior and interfacing surfaces;   an exterior panel including an exposed exterior surface, an opposite interfacing surface for interfacing with the interior panel or a material sandwiched between the interior panel and the exterior panel when the panel system is assembled, and edge surfaces between the exterior and interfacing surfaces;   wherein each panel comprises a cementitious material including:
 a shell layer providing a respective interior or exterior surface, the shell layer comprising a light-weight aggregate and reinforcing fibers dispersed and bonded in a cementitious matrix; and 
 a substrate layer adjacent the shell layer and providing the interfacing surface, the substrate layer comprising a light-weight aggregate dispersed and bonded in a cementitious matrix, the substrate layer being substantially void of reinforcing fibers; 
   wherein a plurality of the interior panels are directly or indirectly attached to a plurality of the exterior panels to form a wall system where interfacing surfaces of respective panels are oriented towards one another in a manner such that seams defined between adjacent edges of the interior and exterior panels are staggered when the panel system is assembled.   
     
     
         10 . A light-weight modular panel wall construction system as recited in  claim 9 , wherein the wall system provides a strength that is greater than a strength of any individual panel within the wall system. 
     
     
         11 . A light-weight modular panel wall construction system as recited in  claim 9 , wherein the light-weight aggregate has a density of not more than about 25 lbs/ft 3  and provides the resulting cementitious material of the panel with the ability to be cut, sanded, drilled, screwed, and shaped with common woodworking tools. 
     
     
         12 . A light-weight modular panel wall construction system as recited in  claim 11 , wherein the interfacing surfaces of one or more of the interior or exterior panels are shaped with common woodworking tools to receive one or more of electrical conduit, electrical wiring, plumbing, seismic tie downs, or other internal wall components. 
     
     
         13 . A light-weight modular panel wall construction system as recited in  claim 9 , further comprising a foam core sandwiched between the interior panels and the exterior panels of the wall system. 
     
     
         14 . A light-weight modular panel wall construction system as recited in  claim 13 , wherein portions of the foam core are removed to provide space for one or more of electrical conduit, electrical wiring, plumbing, seismic tie downs, or other internal wall components. 
     
     
         15 . A light-weight modular panel wall construction system as recited in  claim 9 , wherein each interior and exterior panel has a thickness from about 1.5 inches to about 2 inches, and any foam core sandwiched between the interior panels and the exterior panels has a thickness of up to about 9 inches so that the wall system formed by interfacing interior panels with exterior panels separated by an optional foam core has a thickness of about 3 inches to about 13 inches. 
     
     
         16 . A light-weight modular panel wall construction system as recited in  claim 9 , wherein the exposed exterior surface of each exterior panel and the exposed interior surface of each interior panel includes a finished surface such that no additional surface finishing is required. 
     
     
         17 . A wall system constructed from a plurality of light-weight modular panels, the wall system comprising:
 a plurality of interior panels, each including an exposed interior surface, an opposite interfacing surface for interfacing with an exterior panel or a material sandwiched between the interior panel and an exterior panel, and edge surfaces between the interior and interfacing surfaces;   a plurality of exterior panels, each including an exposed exterior surface, an opposite interfacing surface for interfacing with the interior panel or a material sandwiched between the interior panel and the exterior panel, and edge surfaces between the exterior and interfacing surfaces;   wherein each panel comprises a cementitious material including:
 a shell layer providing a respective interior or exterior surface, the shell layer comprising a light-weight aggregate and reinforcing fibers dispersed and bonded in a cementitious matrix; and 
 a substrate layer adjacent the shell layer and providing the interfacing surface, the substrate layer comprising a light-weight aggregate dispersed and bonded in a cementitious matrix, the substrate layer being substantially void of reinforcing fibers; 
   wherein the plurality of interior panels are directly or indirectly attached to the plurality of exterior panels to form a wall system where interfacing surfaces of respective panels are oriented towards one another in a manner such that seams defined between adjacent edges of the interior and exterior panels are staggered.   
     
     
         18 . A wall system constructed from a plurality of light-weight modular panels as recited in  claim 17 , wherein seams between adjacent interior panels and seams between adjacent exterior panels are spanned with a fiberglass mesh bonded to the respective panels with a polymer modified cement based adhesive so that the wall system provides a strength that is greater than a strength of any individual panel within the wall system. 
     
     
         19 . A light-weight modular panel wall construction system as recited in  claim 17 , wherein the light-weight aggregate has a density of not more than about 25 lbs/ft 3  and provides the resulting cementitious material of the panel with the ability to be cut, sanded, drilled, screwed, and shaped with common woodworking tools. 
     
     
         20 . A light-weight modular panel wall construction system as recited in  claim 17 , further comprising a foam core sandwiched between the interior panels and the exterior panels of the wall system. 
     
     
         21 . A light-weight modular panel wall construction system as recited in  claim 20 , wherein portions of the foam core are removed to provide space for one or more of electrical conduit, electrical wiring, plumbing, seismic tie downs, or other internal wall components. 
     
     
         22 . A light-weight modular panel wall construction system as recited in  claim 20 , wherein each interior and exterior panel has a thickness from about 1.5 inches to about 2 inches, and the foam core sandwiched between the interior panels and the exterior panels has a thickness of about 3 inches so that the wall system formed by interfacing interior panels with exterior panels separated by the foam core has a thickness of about 6 inches to about 7 inches.