Modular curvilinear staircase

Abstract

Provided as a curved staircase which extends between upper and lower levels of a building structure. The building structure has a plurality of spaced vertical wall studs. The curved staircase comprises a plurality of step modules each including a side panel, a front riser and a back riser. Each of the step modules is disposed in stacked relationship to one another to define a plurality of module joints. Each one of the step modules includes a tread which is mounted on the back riser and side panel as well as on the front riser of the next lowest step module. Inner and outer reinforcing panels are disposed in overlapping relationship to the step modules in order to interconnect the step modules.

1 . A curved staircase extending between upper and lower levels of a structure having a plurality of spaced vertical wall studs, the curved staircase comprising: 
 a plurality of step modules each including a side panel, a front riser and a back riser, the front and back risers extending laterally outwardly from the side panel and being connectable to one of the wall studs, each one of the step modules being disposed in stacked relationship to one another to define a plurality of module joints;    a plurality of treads mounted on the back riser and side panel of respective ones of the step modules;    a plurality of inner reinforcing panels disposed in overlapping relationship to the side panels of adjacent ones of the step modules for interconnection thereof; and    a plurality of outer reinforcing panels disposed in overlapping relationship to the inner reinforcing panels for interconnection thereof.    
   
   
       2 . The curved staircase of  claim 1  wherein: 
 the side panel is arcuately shaped and having an outer convex surface and an inner concave surface;    the front and back risers being disposed in overlapping relation to one another and extending laterally outwardly from the convex surface.    
   
   
       3 . The curved staircase of  claim 1  further including: 
 a plurality of treads;    wherein: 
 the side panel and back riser of each one of the step modules are formed at a riser height and have upper edges that are generally flush with one another;  
 the front riser of each one of the step modules having an upper edge extending upwardly past the upper edges of the side panel and back riser to a level equal to that of the riser height;  
 the tread of each one of the step modules being mounted on the respective ones of the back riser and on the front riser extending upwardly from the step module located immediately below.  
   
   
   
       4 . The curved staircase of  claim 1  wherein: 
 the wall studs are radially arranged and collectively define a radius of curvature;    the side panel having a semi-circular shape that is concentric with the radius of curvature of the wall studs.    
   
   
       5 . The curved staircase of  claim 1  further including a strap member connecting the curved staircase to the upper level.  
   
   
       6 . The curved staircase of  claim 5  wherein: 
 the upper level includes a rafter system comprising a plurality of horizontal roof rafters;    the strap member being attached to an uppermost one of the step modules and wrapping around a lower edge of the side panel and extending upwardly to one of the roof rafters for interconnecting the curved staircase to the upper level.    
   
   
       7 . The curved staircase of  claim 1  further including a strap member connecting the curved staircase to the lower level.  
   
   
       8 . The curved staircase of  claim 7  wherein the strap member is attached to a lowermost one of the step modules and extending laterally outwardly along the lower level.  
   
   
       9 . The curved staircase of  claim 1  wherein the side panel is comprised of a plurality of laminated members.  
   
   
       10 . The curved staircase of  claim 1  wherein the side panel is formed of bonded particulate material.  
   
   
       11 . The curved staircase of  claim 10  wherein the particulate material is selected from the group consisting of cellulose fiber, shredded paper, wooden particles, sawdust, and combinations thereof.  
   
   
       12 . The curved staircase of  claim 1  wherein the front and back risers are fabricated of plywood.  
   
   
       13 . The curved staircase of  claim 3  wherein the tread is fabricated of plywood.  
   
   
       14 . A curved staircase extending between upper and lower levels of a structure having a plurality of spaced vertical wall studs, the curved staircase comprising: 
 a plurality of step modules each including a side panel, a front riser and a back riser, the side panel being arcuately shaped and having an outer convex surface and an inner concave surface, the front and back risers extending laterally outwardly from the side panel and being connectable to one of the wall studs, each one of the step modules being disposed in stacked relationship to one another to define a plurality of module joints;    a plurality of tapered treads mounted on upper edges of the back riser and side panel of respective ones of the step modules and on an upper edge of the front riser of the next lower step module; and    a plurality of inner reinforcing panels disposed in overlapping relationship to the concave surfaces of the side panels of adjacent ones of the step modules for interconnection thereof, the inner reinforcing panels abutting one another to form a plurality of inner panel joints disposed in staggered relationship to the module joints;    a plurality of outer reinforcing panels disposed in overlapping relationship to the inner reinforcing panels for interconnecting adjacent ones of the inner reinforcing panels, the outer reinforcing panels abutting one another to form a plurality of outer panel joints disposed in staggered relationship to the inner panel joints.    
   
   
       15 . The curved staircase of  claim 14  wherein the side panel is comprised of a plurality of laminated members.  
   
   
       16 . The curved staircase of  claim 14  wherein the side panel is formed of bonded particulate material.  
   
   
       17 . The curved staircase of  claim 14  wherein the front and back risers are fabricated of plywood.  
   
   
       18 . A step module for forming a curved staircase adjacent to a plurality of vertical wall studs, the step module comprising: 
 an arcuate side panel having an outer convex surface and an inner concave surface; and    a front riser and a back riser disposed in overlapping relation to one another and extending laterally outwardly from the convex surface and being connectable to one of the wall studs.    
   
   
       19 . The step module of  claim 18  further including: 
 a tread;    wherein: 
 the side panel and back riser are formed at a riser height and have upper edges that are generally flush with one another;  
 the front riser extending upwardly past the upper edges of the side panel and back riser to a level equal to that of the riser height;  
 the tread being mounted on the upper edges of the back riser and side panel.  
   
   
   
       20 . The step module of  claim 19  wherein: 
 the wall studs are radially arranged and collectively define a radius of curvature;    the side panel having a semi-circular shape that is concentric with the radius of curvature of the wall studs.