Window backdam assembly for preventing water intrusion

Abstract

A window backdam assembly includes an elongate backdam placed flat on top of a window sill near an interior end. A portion of the window sill adjacent to the exterior end is temporarily uncovered. A one-piece waterproof adhesive material is placed over the entire backdam and uncovered portion of the window sill. The elastic adhesive material is generously sized to cover the backdam, the uncovered window sill, and lower portions of the jambs of the window frame and structural panel. Thin flashing material may be applied horizontally to the structural panel beneath the sill, vertically along the two jambs of the panel, and horizontally on the top portion of panel, thereby forming a border around the panel opening.

1 . A window assembly for preventing water intrusion, comprising:
 a window sill including a surface with an exterior end, an interior end, a surface depth defined between the interior end and the exterior end, and a surface width;   an elongate material having a height of at least 0.1 inch, a material depth greater than the height and less than the surface depth, and a material width that is substantially similar to the surface width, the elongate material being disposed on top of the horizontal bottom surface adjacent to the interior end such that the elongate material does not cover a portion of the bottom surface adjacent to the exterior end; and   a one-piece waterproof adhesive material disposed over the elongate material and the portion of the bottom surface adjacent to exterior so as to create a slope directing any liquids on top of adhesive outwardly toward the exterior end of the bottom surface.   
   
   
       2 . The assembly of  claim 1 , wherein the elongate material comprises plywood. 
   
   
       3 . The assembly of  claim 1 , wherein the material depth is less than the surface depth such that the elongate material does not cover a portion of the bottom surface adjacent to the exterior end. 
   
   
       4 . The assembly of  claim 1 , wherein the height of the material is less than 0.75 inches. 
   
   
       5 . The assembly of  claim 1 , wherein the material depth is between 0.5 inches and 3 inches. 
   
   
       6 . The assembly of  claim 1 , further comprising:
 a frame defining a window opening, the frame comprising the window sill, an interior side and an exterior side; and   at least one structural panel coupled to the exterior side of the frame, the structural panel including a bottom portion disposed beneath the window sill.   
   
   
       7 . The assembly of  claim 6 , wherein the window sill comprises a first side and a second side, the first side and the second side defining the surface width, the assembly further comprising:
 a flashing coupled to the bottom portion of the structural panel, the flashing extending horizontally beyond the first side and the second side of the window sill.   
   
   
       8 . The assembly of  claim 6 , wherein the at least one structural panel comprises oriented strand board. 
   
   
       9 . A method for forming a window assembly that prevents water intrusion, comprising:
 providing a window frame with a window sill having an interior end and an exterior end;   providing a backdam having a height, a width, and a depth greater than the height;   placing the backdam horizontally flat on the window sill adjacent to the interior end so to as temporarily expose a portion of the window sill adjacent to the exterior end; and   covering the backdam and the exposed portion of the window sill with a one-piece adhesive material.   
   
   
       10 . The method of  claim 9 , further comprising:
 providing a structural panel having at least a bottom portion; and   coupling the structural panel to an exterior side of the window frame.   
   
   
       11 . The method of  claim 10 , further comprising:
 applying a flashing horizontally to the bottom portion of the structural panel beneath the window sill; and   wherein covering the backdam and the exposed portion of the window sill with the one-piece adhesive material comprises covering the flashing disposed beneath the window sill.   
   
   
       12 . The method of  claim 9 , wherein covering the backdam and the exposed portion of the window sill with the one-piece adhesive material comprises covering the backdam and the exposed portion of the window sill with a waterproof adhesive material. 
   
   
       13 . The method of  claim 9 , wherein providing the backdam having the height, the width, and the depth greater than the height comprises forming the backdam from plywood. 
   
   
       14 . The method of  claim 1 , wherein providing the backdam having the height, the width, and the depth greater than the height comprises forming the backdam with a backdam width that corresponds to a width of the sill. 
   
   
       15 . A method for forming a window assembly that prevents water intrusion, the window assembly being included as part of a building, comprising:
 providing a first material being used in constructing the building;   providing a waterproof adhesive material being used in constructing the building;   providing a window frame with a window sill having an interior end and an exterior end;   providing a backdam composed of the first material;   forming the backdam with a height, a width, and a depth greater than the height;   placing the backdam horizontally flat on the window sill adjacent to the interior end so to as temporarily expose a portion of the window sill adjacent to the exterior end; and   covering the backdam and the exposed portion of the window sill with the waterproof adhesive material.   
   
   
       16 . The method of  claim 15 , further comprising:
 providing a structural panel having at least a bottom portion; and   coupling the structural panel to an exterior side of the window frame.   
   
   
       17 . The method of  claim 16 , further comprising:
 applying a flashing horizontally to the bottom portion of the structural panel beneath the window sill; and   wherein covering the backdam and the exposed portion of the window sill with the waterproof adhesive material comprises covering the flashing disposed beneath the window sill.   
   
   
       18 . The method of  claim 15 , wherein providing the backdam composed of the first material comprises forming the backdam from plywood. 
   
   
       19 . The method of  claim 15 , wherein providing the backdam having the height, the width, and the depth greater than the height comprises forming the backdam with a backdam width that corresponds to a width of the sill.