Flashing method using air infiltration blocking skirt

Abstract

An air infiltration blocking skirt comprising a weather resistant sheet material is attached to the lower portion of a window to be installed in a wall opening the full width of the opening and sufficiently long to extend over the wall immediately below the window. The skirt is sealed to the wall along both the left and right sides of the skirt while the bottom edge remains unsealed. The skirt prevents wind-driven rain and air from penetrating the window-wall interface while allowing moisture to drain therethrough.

1 . A method for flashing a window during the installation of the window into a wall opening using an air infiltration blocking skirt comprising a piece of weather resistant sheet material, the skirt having a top edge, a bottom edge and two side edges, and having a width at least equal to the width of the window and a length sufficient for the skirt to extend below the lowest portion of the wall opening, wherein: 
 a) the top edge of the skirt is attached to the lower portion of the window continuously along the width thereof,    b) the window is installed in the wall opening,    c) the side edges of the skirt are sealed to the wall,    whereby the skirt covers the exterior surface of the wall below the window and the bottom edge of the skirt is not completely sealed to the wall such that a drainage path is maintained.    
   
   
       2 . The method of  claim 1 , wherein the length of the air infiltration blocking skirt is sufficient for the skirt to extend at least approximately 4 inches below the lowest portion of the wall opening.  
   
   
       3 . The method of  claim 1 , wherein the window is a nonflanged window having a lower surface and the air infiltration blocking skirt is attached to the lower surface of the window.  
   
   
       4 . The method of  claim 1 , wherein the window is a flanged window having a lower flange having an exterior-facing side and an interior-facing side, and the air infiltration blocking skirt is attached to exterior-facing side of the flange of the window.  
   
   
       5 . An air infiltration blocking skirt for use with a fenestration product in a wall opening in a structure, comprising a weather resistant sheet material, having a top edge and a bottom edge, wherein the top edge of the skirt has an adhesive surface suitable for attaching the skirt to the bottom end of the fenestration product and the skirt is at least as wide as the wall opening and is of sufficient length to extend below the lowest portion of the wall opening.  
   
   
       6 . The skirt of  claim 5 , wherein the length is sufficient to extend at least about 4 inches below the bottom of the wall opening.  
   
   
       7 . The skirt of  claim 5 , wherein the weather-resistant sheet material is a flashspun polyethylene sheet.