Abstract:
A flashing system and associated method controls water and air intrusion around the sills of windows, doors, louvers and other wall penetrations. More specifically, a sheet material is creased and folded to form a sill flashing component to control water and air intrusion. Prior to this invention, a separate pre-molded termination accessory was required to effectively seal corner areas around window and door rough openings. The invention provides for sill flashing and supplemental sealing at selected joint locations prior to installation of a closure member in the opening to prevent water and air intrusion around windows, doors and other building openings.

Description:
[0001]     This claims the benefit of U.S. Provisional Patent Application Ser. No. 60/628,327, filed Nov. 16, 2004 and hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates in general to prohibiting weather-related moisture from entering a building and, in particular, to a sill pan and threshold flashing unit for window and door openings in a building.  
         [0003]     In recent years, many attempts have been made to find a solution to the ever present problem of unwanted water and air intrusion into buildings. Historically, flashing is the term used to identify the means or components utilized to prevent water intrusion. In this invention, the flashing can be used to control water intrusion and/or air intrusion. Controlling water and air intrusion is a very serious concern which may result in exterior and interior damage if not prevented or corrected in a timely manner. Recent studies have shown that the extent of such damage, on an annual basis, has run into millions of dollars. In addition, heat loses through air leakage around window, door and louver openings have taken on new significance due to today&#39;s high energy costs. It has become imperative that a more serious approach be taken to control water and air intrusion to reduce heating costs.  
         [0004]     In the past, one method for dealing with the potential for water intrusion at a door or window frame opening in an exterior building wall was to provide a pre-formed sill pan to collect and control the water. This objective was accomplished with preformed plastic or metal pieces mounted along the sill of the opening in the wall construction, to protect the underlying material from damage. However, such sill pans have proven to be too expensive for all building applications. The high cost of manufacture and wide variety of sizes required for a vast array of door and window opening sizes has limited the desirability of this type of device for more widespread application.  
         [0005]     Alternatively, a surface sealed approach has been used. Putty-like components are used to caulk around openings between the window and door frames in an attempt to seal the gaps and prevent inward seepage of water and air into the building. However, after a period of time, the putty-like compounds had a tendency to dry up, shrink and produce gaps or openings. This provides a passageway for water and air to penetrate the building enclosure ultimately resulting in deterioration beneath the window and door frames at the sheathing or structural components adjacent thereto.  
         [0006]     Tar is another option that has been used. The application of a wad of tar at strategic locations surrounding the window or door opening may be economical, but it is seldom effective over the long term. Moreover, it is very messy and difficult to efficiently apply.  
         [0007]     In an effort to overcome the inadequacies inherent with caulking and tar, advances in the chemical field have produced new sealant materials which are better equipped to withstand the sun, temperature variations and exposure to the elements for a longer period of time. Nevertheless, these improved sealants eventually break down or are not initially installed properly resulting in water and air intrusion. Something more than caulking, tar and sealants is desirable and new flashing materials and techniques are needed to provide long-term and economical protection against water and air intrusion.  
         [0008]     Known prior art attempts to provide flashing devices for the sills of window and door openings are disclosed in U.S. Pat. Nos. 993,861; 1,677,130; 4,555,882; 5,899,026; 6,401,401; and 6,401,402, each of which is hereby incorporated by reference entirely.  
         [0009]     All known approaches suffer from significant problems, including limited long-term effectiveness, inability to economically accommodate a variety of opening sizes, substantial expense, limited operating temperature ranges, labor intensive construction and installation procedures, and unreliable moisture penetration prevention.  
         [0010]     In view of the above described conditions and consequences of prior art solutions, a need exists for a weatherproofing solution for window and door opening sills or thresholds that is not subject to these shortcomings and installation errors and lasts the life of the building structure.  
       SUMMARY OF THE INVENTION  
       [0011]     These and other problems in the prior art have been overcome by this invention which in one embodiment includes a number of flexible membrane flashing components utilized in combination as a uniquely formed termination accessory for providing sill or threshold and end dam corner protection at the sill or threshold areas of a roughed-in window door or other opening. The flashing of this invention seals the sill or threshold of the opening with or without the use of pre-formed or molded termination accessory units in the lower left and right corners of the opening.  
         [0012]     As a result of unique components and their associated installation and folding sequence, a sill or threshold flashing is created to form the required closure at the corner areas thus eliminating the need for a termination accessory unit of the type previously utilized. The uniquely folded and assembled flashing components of this invention are creased and folded and formable in a variety of sizes which can then be cut in-situ by the installer to the required dimensions of a particular job. It has been found that a typical window sill rough opening can be completely flashed by utilizing a single section of the flashing membrane by installing it in a particular sequence with associated components to form a pair of folded end dams.  
         [0013]     In one embodiment of this invention, the flashing system for preventing intrusion of water and air through the sill or threshold areas of an opening in a wall for a window, a door, and other through wall penetrations includes a sill pan membrane having a top face and a bottom face. A first portion of the sill pan membrane is adapted to be positioned on the sill or threshold and an adjacent portion of a jamb of the wall opening. A second portion of the sill pan membrane is adapted to extend rearwardly from the sill or threshold and jambs of the wall opening. The second portion is adapted to be formed into a sill rear dam adjacent the sill or threshold and jambs of the wall opening. The sill pan membrane includes a first adhesive layer on the bottom face of the first portion of the sill pan membrane and a second adhesive layer on the top face of the second portion. The adhesive layers each may include a pressure sensitive self adhesive applied generally uniformly and continuously over the respective faces of the associated portions of the sill pan membrane.  
         [0014]     The flashing system also includes in one embodiment a pair of sill end dams formed by folds in the sill pan membrane. Each sill end dam is adapted to be juxtaposed to a juncture of the sill or threshold and one jamb of the wall opening. A pair of juncture sealing strips are each adapted to be applied at one of the junctures of the sill and one of the jambs and over the sill pan membrane when installed in the wall opening. A front downwardly depending flange formed in the sill pan membrane is adapted to be juxtaposed to the wall opening subjacent to the sill and jambs thereof. A pair of gusset folds in the sill pan membrane are each adapted to be positioned proximate a juncture between the sill and one jamb of the wall opening. Further, a pair of termination membranes are each adapted to at least partially overlap one another and be applied adjacent the juncture of the sill or threshold and one of the jambs over the sill pan membrane when installed in the wall opening. One of the termination membranes is adapted to be applied on the sill or threshold of the wall opening and extend forwardly and outwardly therefrom toward the adjacent jamb and the other termination membrane is adapted to be applied on the jamb of the wall opening and extend forwardly and downwardly therefrom. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The objectives and features of the invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:  
         [0016]      FIG. 1A  is front elevational view of an exemplary rough opening in a wall with selected sill pan flashing components according to one embodiment of this invention installed therein;  
         [0017]      FIG. 1B  is a view similar to  FIG. 1A  with the flashing components and a window installed in the opening in the wall;  
         [0018]      FIG. 2  is a perspective view of a membrane sheet from which the sill plan flashing component of  FIG. 1A  can be formed according to this invention;  
         [0019]      FIG. 2A  is a perspective view from the rear of the membrane sheet of  FIG. 2  folded into the sill pan flashing component when installed in the rough opening in the wall;  
         [0020]      FIGS. 3-4  are perspective views of additional flashing components according to one embodiment of this invention to be installed at a juncture of the sill and a jamb of the rough opening; and  
         [0021]      FIGS. 5A-5D  are sequential perspective views of components of the sill pan flashing kit according to one embodiment of this invention being installed in the rough opening. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0022]     Referring to  FIGS. 1A-1B , one embodiment of the components of a sill pan flashing kit  10  is shown installed along the sill  12  and adjacent lower portions of jamb members  14  in a rough opening  16  in a wall  18  intended to receive a window frame  20 , door frame (not shown) or the like. The opening  16  also includes a header  22  spaced from the sill  12  and extending between the spaced jamb members  14 . While the flashing kit  10  is shown and described with respect to a window frame  20  and associated opening  16 , it should be readily appreciated that the kit can be utilized for other wall openings, door thresholds and the like. As such, the term sill or variations thereof is used herein without limiting the invention to exclude door thresholds or any other application.  
         [0023]     One component of an embodiment of the sill pan flashing kit  1 o according to this invention is a flexible sill pan membrane  24  shown particularly in  FIGS. 1A and 2 . In one embodiment, the flexible sill pan membrane  24  is a polyethylene cross-laminated sheet, although other materials may be readily utilized within the scope of this invention. The sill pan membrane  24  has a top face  26  and a bottom face  28 . The sill pan membrane  24  is adapted to be installed along the sill  12  of the rough opening  16  and folded along fold lines  30  as shown in  FIG. 2  to extend upwardly along the lower portion of each jamb  14  in the rough opening  16 . The sill pan membrane  24  also has a fold line  32  extending substantially the entire width of a central sill region  34  of the membrane  24 . The fold line  32  separates a sill region  34  of the membrane from a front downwardly depending flange  36  of the membrane  24  adapted to cover the front face  38  of the wall  18  underlying the sill  12  as shown in  FIGS. 1A and 1B . The sill pan membrane  24  is preferably cut or sliced along lines  40  and along the fold line  32  at the outward lateral ends thereof so that the jamb panel  42  of the sill pan membrane  24  can be applied to the jambs  14  of the rough opening  16  and the downwardly depending flange portion  36  can likewise be installed as shown in  FIGS. 1A and 1B .  
         [0024]     Advantageously, the sill pan membrane  24  includes two distinct portions  44 ,  46 . A first adhesive layer  48  is on the bottom face  28  of the first portion  44  of the sill pan membrane  24  as shown in  FIG. 2 . A second adhesive layer  50  is positioned on the top face  26  of the second portion  46  of the sill pan membrane  24 . The second portion  46  containing the second adhesive layer  50  is separated from the first portion  44  of the membrane  24  by a fold line  52  extending substantially the entire major dimension of the sill pan membrane  24 . In one embodiment, the first and second adhesive layers  48 ,  50  may be rubberized asphalt adhesive or a pressure-sensitive adhesive (PSA) and covered by a protective peel strip  48   a ,  50   a  until the sill pan membrane  24  is to be installed in the rough opening  16 .  
         [0025]     The sill pan membrane  24  also includes an angular fold line  54  in each outward lateral corner area  56  of the second portion  46  as shown in  FIG. 2 . The function of these angular fold lines  54  will be described later herein.  
         [0026]     Additional components of the flashing kit  10  according to one embodiment of this invention include a pair of juncture sealing strips  58 , each adapted to be applied at one of the junctures of the sill  12  and one of the jambs  14  of the rough opening  16 . The juncture sealing strips  58  are intended primarily to block exposed corners  60  formed in the sill pan membrane  24  when it is initially installed in the rough opening  16  as shown in  FIG. 1A . The juncture sealing strips  58  preferably include an adhesive on one surface thereof for application of the juncture sealing strip  58  over top of the top face  26  of the sill pan membrane  24 . The juncture sealing strips  58  cover the juncture between the associated jamb  14  and sill  12  of the rough opening  16  on top of the sill pan membrane  24  and extend downwardly and outwardly therefrom to the front face  38  of the wall  18  adjacent the rough opening  16 .  
         [0027]     The flashing kit  10  according to one embodiment of this invention also includes a pair of termination membranes  62 ,  64  ( FIGS. 3 and 4 ) which are particularly adapted for installation at the left end of the sill  12  as shown in  FIGS. 1A and 1B . One of ordinary skill in the art will appreciate that complementary termination membranes, which are mirror images of those shown in FIGS.  3  and  4 , are utilized at the right side end of the sill  12  according to this invention. The termination membranes  62 ,  64  are each adapted to at least partially overlap one another and be applied adjacent the juncture of the sill  12  and one of the jambs  14  over the sill pan membrane  24  and juncture sealing strips  58  when installed in the wall opening. The termination membrane  64  shown in  FIG. 4  includes a generally rectangular portion  66  separated by a fold line  68  from a downwardly depending flange  70  having an angular edge  72 . The rectangular portion  66  of the termination membrane  64  of  FIG. 4  is intended to overlap the sill pan membrane  24  on the sill  12  of the rough opening  16  with edge  74  of the membrane  64  juxtaposed to the jamb  14 . The downwardly depending flange  70  is intended to overlap a portion of the flange  36  of the sill pan membrane  24  and be folded downwardly along the fold line  68 . The angular outwardly projecting edge  72  extends outwardly from the rough opening  16  as shown in  FIG. 5B .  
         [0028]     The other termination membrane  62  of  FIG. 3  includes a pair of rectangular portions  76 ,  78  separated by a fold line  80 . The termination membrane  62  is intended to be applied along the jamb  14  of the rough opening  16  adjacent to the sill  12 . The downwardly projecting portion  78  of the termination membrane  62  extends below the sill  12  of the rough opening  16  and overlaps the angular projection  72  of the termination membrane  64 . The termination membranes  62 ,  64  each include an adhesive layer  62   a ,  64   a  on a bottom face thereof for convenient and easy application and installation.  
         [0029]     The installation of the components of the flashing kit  10  according to this invention is shown sequentially in  FIGS. 5A-5D . Prior to installing the flashing kit  10 , any housewrap should be removed from the sill  12  and adjacent portions of the jambs  14 . The surfaces of the sill  12  and jambs  14  should be smooth, dry and free from dirt, debris, ice and other foreign material. These surfaces of the sill  12  and jambs  14  should be primed.  
         [0030]     The sill  12  of the rough opening  16  is covered by the sill region  34  and sill pan membrane  24  as shown in  FIGS. 1A and 5A  with the second portion  46  extending rearwardly from the rough opening  16  and the downwardly depending flange  36  positioned along the face  38  of the wall  18  subjacent to the rough opening  16  as shown in  FIGS. 1A and 5A . Advantageously, the first adhesive layer  48  on the bottom face  28  of the first portion  44  of the sill pan membrane  24  securely mounts the sill pan membrane  24  to the sill  12  and lower jamb portions  14  once the peel strip  48   a  is removed. Then the membrane  24  is folded along the fold lines  30  and slit or cut along cut lines  40 . The sill pan membrane  24  may be conveniently cut from a roll of membrane material to a length appropriate for the size of the sill  12  and rough opening  16  to be flashed. The first portion  44  should extend about three inches up each jamb  14  from the sill  12 . One technique for installing the first portion  44  of the sill pan membrane  24  is to begin application on one of the jambs  14  and proceed downwardly toward the sill  12 , across the sill  12  and then up the other jamb  14 , removing the peel strip  48   a  as needed.  
         [0031]     Next, the juncture sealing strips  58  are installed at the juncture between each jamb  14  and the sill  12  as shown in  FIGS. 1A and 5A  to cover the exposed corners  60 . Additional flashing protection is provided by the installation of the termination membranes  62 ,  64 . The termination membrane  64  is installed as shown in  FIG. 5B  adhesively secured in place on top of portions of the sill pan membrane  24  and juncture sealing strip  58 .  
         [0032]     Next, the termination membrane  62  is installed along the lower portion of the jamb  14  adjacent the sill  12  to cover the exposed portion of the juncture sealing strip  58  and the jamb portions  42  of the sealing membrane  24 . Likewise, the angular projecting portion  72  of the termination membrane  64  is also covered by the downwardly projecting portion  78  of the termination membrane  62 . Once the sill membrane  24 , juncture strips  58  and termination membranes  62 ,  64  are installed as shown and described in  FIGS. 5A-5C  for both jamb portions  14  of the rough opening  16 , the window frame  20 , door frame or the like is installed in the rough opening  16  as shown in  FIG. 1B .  
         [0033]     A sill rear dam  82  is then formed in the second portion  46  of the sill pan membrane  24  as shown in  FIG. 5D . After the peel strip  50   a  is removed, the second adhesive layer  50  is exposed on the second portion  46  of the sill pan membrane  24 . The second portion  46  is then folded upwardly along the fold line  52  as shown by arrow A in  FIG. 5D . Advantageously, the second adhesive layer  50  is on the top face  26  of the sill pan membrane  24 . When the second portion  46  is folded upwardly, it is likewise folded along each of the angular fold lines  54  to form a gusset  84  extending outwardly from the rough opening  16  as shown by arrow B in  FIG. 5D  and attached to the frame  20 . The confronting surfaces of the corner area  56  on the second portion  46  of the sill pan membrane  24  contain portions of the second adhesive layer  50  and are therefore readily sealed with each other to form the gusset and maintain the second portion  46  of the sill pan membrane  24  into the sill rear dam  82  adjacent the jambs  14  of the wall opening  16 . The configuration of the sill pan membrane  24  when cut and folded is shown from a rear perspective view in  FIG. 2A . Once folded into this configuration, fasteners such as staples, tacks, nails or the like  86  may be inserted through the rear of the sill rear dam  82  and into the wall  18  and/or window frame  20  installed in the rough opening  16 .  
         [0034]     After the components of the flashing kit lo are assembled and installed as described and shown herein, the window frame  20 , door frame or the like may be inserted into the rough opening  16  as shown in  FIG. 1B  with the sill area thereof being sealed against air and water intrusion through the wall  18 . Advantageously, the materials of the flashing kit lo according to one embodiment of this invention do not tear or deform when the frame  20  is being installed in the rough opening  16  nor do they mar or fowl the frame  20  as with prior art materials such as tar and the like. The sill rear dam  82  can be formed with the gussets  84  after the frame  20  is installed and then tacked to the frame  20  as shown in  FIG. 2A .  
         [0035]     Advantageously, the membrane  24  can be cut and sized to flash the sill  12  of an opening  16  of any size in the wall  18  on-site thereby providing an efficient and economical solution to inhibit water and moisture from entering the building structure through the opening  16 .  
         [0036]     The various components of the flashing kit  10  according to this invention may be made of any of a variety of known materials suitable for flashing a rough opening  16  in a wall  18 . Presently preferred materials for the membrane are uncured rubber, cured rubber and cross-laminated polyethylene. Another material for the flashing member  24  according to this invention is Flexwrap™ commercially available from Tyvek®. Generally, the Flexwrap™ product is a butyl compound containing melamine, cyanurate and aluminum hydroxide as fire retardants. The adhesive  32  may be a pressure sensitive adhesive (PSA) or butyl adhesive containing a non-halogen fire retardant additive and is covered with a release liner or peel strip as is well known. Other materials which may be suitable for one or more of the components of the flashing kit  1 o of this invention may be sheet metal, with or without adhesive for mounting to the opening  16  in the wall  18 .  
         [0037]     Preferably, the membrane  24  is available in roll form and can be cut to the approximate dimensions. The membrane  24  is provided with the peel strips  48   a ,  50   a  and a pressure sensitive adhesive  48 ,  50  on opposite sides. Finger pressure is applied to insure good contact and removal of any air bubbles which may reside thereunder. Again, as with the silicone rubber adhesive sealant, this product readily bonds and adheres to the itself and the surface on which it is applied.  
         [0038]     As can be seen from the foregoing drawings and their descriptions, there has been set forth several embodiments and options available to a builder to prevent water and air intrusion around windows and door openings. This system provides an economical, less time consuming, effective procedure for solving a very serious problem in the construction industry.  
         [0039]     From the above disclosure of the general principles of this invention and the preceding detailed description of at least one preferred embodiment, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. Therefore, I desire to be limited only by the scope of the following claims and equivalents thereof.