Prefabricated staircase and finishing arrangement and installation method therefor

Abstract

A staircase of skeletal form is prefabricated and is provided with prefabricated decorative cladding finishing plates for the treads, the risers and the stringer boards, the plates being pre-drilled for ease of assembly, a plurality of finishing plates can be preassembled, or factory assembled, together before installation over a portion of the prefabricated staircase, and the installation method thereof.

1 . A staircase finishing kit for installation over at least a portion of a prefabricated staircase frame having at least one vertical riser, at least one horizontal tread, the frame being connectable at opposing frame ends thereof to first and second floor structures of a building with the frame extending therebetween, the kit comprising:
 at least one prefabricated finished stringer plate having, for each tread, a respective horizontal plate edge in horizontal register therewith, and for each riser a respective vertical plate edge in vertical register with;   for each riser, a respective prefabricated finished riser plate connectable to the at least one stringer plate to cover a respective riser with a top vertical plate edge of the riser plate in vertical register with an adjacent tread and the respective horizontal plate edge therefore and intersecting an adjacent vertical plate edge to form a riser corner therewith; and   for each tread, a prefabricated finished tread plate having a decorative nosing extending along at least a front edge thereof and having a lip for abutment against the adjacent riser, the tread plate being connectable to the at least one stringer plate by intersecting an adjacent horizontal plate edge and to an adjacent riser plate with the tread plate abuttingly covering a respective tread.   
     
     
         2 . The kit of  claim 1 , wherein the prefabricated staircase frame further has at least one stringer board to which each riser and each tread is connected, and wherein at least one said vertical plate edge from at least one said stringer plate is longitudinally mitred for intersection with a mitred lateral edge of a respective said riser plates to form a riser corner therewith. 
     
     
         3 . The kit of  claim 2 , wherein each vertical plate edge and corresponding lateral edge have respective slots extending at least partially therealong and in register with one another for simultaneously receiving a securing member therein thereby securing the riser plate to the stringer plate. 
     
     
         4 . The kit of  claim 3 , wherein said securing member is a securing nail. 
     
     
         5 . The kit of  claim 1 , wherein each horizontal plate edge of said at least one stringer plate extends inwardly from a superjacent vertical plate edge to allow the respective tread plate to intersect said superjacent vertical plate edge and have the respective tread plate locally sandwiched between the stringer plate and the corresponding superjacent riser plate. 
     
     
         6 . The kit of  claim 1 , wherein the at least one prefabricated finished stringer plate is provided with preformed registration points for matching with corresponding positioned registration points on a corresponding stringer board of the prefabricated staircase frame to which each riser and each tread is connected, securing fixtures connect with respective said stringer plate registration points and respective said stringer board registration points for alignment and securement of the stringer plate to the stringer board. 
     
     
         7 . The kit of  claim 6 , wherein said registration points are predrilled dowel holes and said securing fixtures are dowels adapted to register with corresponding said stringer plate and board registration points. 
     
     
         8 . The kit of  claim 1 , wherein the decorative nosing includes a plurality of spaced apart spike members extending horizontally inwardly beneath the tread plate from the lip thereof, the tread plate being connectable to an adjacent riser with the tread plate abuttingly covering the tread by insertion of the spike members through the adjacent riser plate and into the adjacent riser with the lip abutting against the adjacent riser. 
     
     
         9 . The kit of  claim 1 , wherein the kit is factory assembled and covers a plurality of steps of the prefabricated staircase. 
     
     
         10 . A staircase comprising:
 a prefabricated staircase frame having at least one vertical riser, at least one horizontal tread, and at least one stringer board to which each riser and each tread is connected, the frame being connectable at opposing frame ends thereof to first and second floor structures of a building with the frame extending therebetween;   at least one prefabricated finished stringer plate having, for each tread, a respective horizontal plate edge, and for each riser a respective vertical plate edge, the stringer plate being connectable to the stringer board to abuttingly cover the stringer board with each respective horizontal plate edge in horizontal register with the tread and with each respective vertical plate edge in vertical register with the respective riser;   for each riser, a respective prefabricated finished riser plate connectable to the riser to cover the riser with a top vertical plate edge of the riser plate in vertical register with an adjacent tread and the respective horizontal plate edge therefore and intersecting an adjacent vertical plate edge to form a riser corner therewith; and   for each tread, a prefabricated finished tread plate having a decorative nosing extending along at least a front edge thereof, the tread plate being connectable to an adjacent riser with the tread plate abuttingly covering the tread by abutment against the adjacent riser plate with a lip of the nosing.   
     
     
         11 . The staircase of  claim 10 , wherein each vertical plate edge from at least one said stringer plate is longitudinally mitred for intersection with a mitred lateral edge of a respective said riser plates to form a riser corner therewith. 
     
     
         12 . The kit of  claim 11 , wherein at least one said vertical plate edge and corresponding lateral edge have respective slots extending at least partially therealong and in register with one another for simultaneously receiving a securing member therein thereby securing the riser plate to the stringer plate. 
     
     
         13 . The kit of  claim 12 , wherein said securing member is a securing nail. 
     
     
         14 . The kit of  claim 10 , wherein each horizontal plate edge of said at least one stringer plate extends inwardly from a superjacent vertical plate edge to allow the respective tread plate to intersect said superjacent vertical plate edge and have the respective tread plate locally sandwiched between the stringer plate and the corresponding superjacent riser plate. 
     
     
         15 . The kit of  claim 10 , wherein the decorative nosing includes a plurality of spaced apart spike members extending horizontally inwardly beneath the tread plate from the lip thereof, the tread plate being connectable to an adjacent riser with the tread plate abuttingly covering the tread by insertion of the spike members through the adjacent riser plate and into the adjacent riser with the lip abutting against the adjacent riser 
     
     
         16 . A method for installing a prefabricated staircase, the method comprising the steps of:
 connecting generally opposed frame ends of a prefabricated staircase frame to first and second floor structures of a building with the frame extending therebetween, the frame having at least one vertical riser, at least one horizontal tread, and at least one stringer board to which each riser and each tread is connected, the frame being connectable at opposing frame ends thereof;   after connecting the generally opposed frame ends, connecting at least one preassembled finishing plate arrangement to at least a portion of the prefabricated staircase frame.   
     
     
         17 . The method of  claim 16 , wherein the at least one preassembled finishing plate arrangement includes at least one prefabricated finished stringer plate, at least one prefabricated finished riser plate and at least one prefabricated finished tread plate, the step of connecting the at least one preassembled finishing plate arrangement includes:
 after connecting the generally opposed frame ends, for each stringer board, connecting a respective prefabricated finished stringer plate therefor to the stringer board to cover the stringer board with, for each tread, a respective horizontal plate edge of the stringer board in horizontal register with the tread, and, for each riser, a respective vertical plate edge in vertical register with the riser;   after connecting each stringer board, for each riser, connecting a respective prefabricated finished riser plate to abuttingly cover the riser with a top horizontal edge of the riser plate in horizontal register with an adjacent tread and the respective horizontal plate edge therefore and intersecting an adjacent vertical plate edge to form a riser corner therewith; and   after connecting a respective prefabricated riser plate, for each tread, connecting a prefabricated finished tread plate, having a decorative nosing forming at least a front edge thereof, to an adjacent riser with the tread plate abuttingly covering the tread by abutment against the adjacent riser plate with a lip of the nosing and with side edges of the tread plate in register with the horizontal plate register.   
     
     
         18 . The method of  claim 17 , wherein the decorative nosing includes a plurality of spaced apart spike members extending horizontally inwardly beneath the tread plate from the lip thereof, and wherein the step of connecting a prefabricated finished tread plate includes connecting a prefabricated finished tread plate to an adjacent riser with the tread plate abuttingly covering the tread by insertion of the spike members through the adjacent riser plate and into the adjacent riser with the lip abutting against the adjacent riser. 
     
     
         19 . The method of  claim 17 , wherein at least one said vertical plate edge from at least one said stringer plate is longitudinally mitred for intersection with a mitred lateral edge of a respective said riser plates to form a riser corner therewith, and said mitred vertical plate edge and said mitred lateral edge have respective slots extending at least partially therealong and in register with one another, and wherein the step of connecting a respective prefabricated finished riser plate includes securing the riser plate to the stringer plate by slidably and simultaneously inserting a securing member into said mitred vertical plate edge and corresponding said mitred lateral edge.