Abstract:
A flashing system configured to reduce moisture intrusion at an opening extending through an exterior treatment of a building structure. The flashing system includes at least one flashing piece having a main flashing portion and a sealing flange. The main flashing portion is configured to extend outward a distance from a periphery of the opening of the building structure to provide an effective moisture barrier and configured to be positioned against a wall having the opening defined therein. The sealing flange of the at least one flashing piece includes a top sealing flange, a bottom sealing flange, a first side sealing flange and a second side sealing flange each configured to extend outward from the main flashing portion and is configured to be positioned adjacent a peripheral-opening-structure at a respective top periphery, bottom periphery, first side periphery and second side periphery of the opening. The flashing system also includes a first top tab and a second top tab. The first top tab configured to extend laterally from the first end of the top sealing flange and configured to extend partially over the first side sealing flange. The second top tab is configured to extend laterally from a second end of the top sealing flange and configured to extend partially over the second side sealing flange. With this arrangement, the first top tab and the second top tab provide a mechanism to interconnect the top sealing flange to the first and second side sealing flanges such that the flashing system substantially reduces moisture intrusion at the opening extending through the exterior treatment of the building structure.

Description:
[0001]    This application claims priority of U.S. provisional application serial No. 60/366,679 filed Mar. 20, 2002. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. The Field of the Invention  
           [0003]    The invention relates generally to water management systems for reducing water intrusion in structures. More specifically, the invention relates to flashing systems and flashing configurations for door, window, and various utility configurations and for eaves and foundation interfaces, chimney structures, and their incorporation with exterior treatment systems, such as stucco, brick, and siding.  
           [0004]    2. The Background Art  
           [0005]    Recently, black mold fungus and other various toxic-type molds have been found growing within the walls of homes and buildings. Such various molds can and have caused a serious health threat to homeowners and building tenants. The cause of such molds has greatly been the result of moisture seeping within the walls of homes and buildings. Conventionally, keeping moisture out of human-built structures has been an ongoing goal and now, having been found a serious health risk, preventing such moisture from entering the walls of homes and buildings is much more serious.  
           [0006]    Wherever openings, such as doors and windows are provided, keeping water from entering the wall structures around such openings has been problematic. Numerous solutions to this problem have been tried, depending on the type of structure involved. Furthermore, the areas where the walls of a building meet the foundation, particularly in wood frame construction, have been recognized as another area where water can enter, because a construction joint of some type typically is provided there. Likewise where the roof meets the walls, and where one type of exterior treatment meets another (for example brick extends part way up a wall and stucco the remainder of the way to the roofline, for example) provision for waterproofing the exterior of the structure has been a concern. For these and other reasons the problem is well recognized in the trades and in the building designer s endeavors.  
           [0007]    One example in modem construction technology is the scaling around doors and windows in a stucco exterior treatment. At the time of application for this patent the current best practice was to install a window in the structure, in which the nailing flanges of the window frame (whether made of polymeric resin, or of aluminum, or some other material) are attached to the exterior sheathing over the frame. This can be before or after tar-paper, a plastic fiber-reinforced and treated paper, such as Tyvek, or other scaling layer is applied to the sheathing. A sealing strip of Vitchathyne, which is a laminate of a polymer sheet and a bituminous sealant layer (e.g. the laminate made by Protecto-Wrap Company of Denver, Colo.) is then laid over the bottom nailing flange and adheres to the flange and paper around the window; and then the strip is usually also stapled to the paper-covered sheathing. Two like sealing strips are then laid down the sides of the window over the nailing flanges and likewise stapled. Then finally a sealing strip is laid over the top window nailing flange, and this strip is usually made long enough to extend outward beyond the sides of the window to lay over the strips laid against the sides of the window. Subsequently the stucco exterior treatment is applied. This usually takes one to several days, depending on when the stucco crew can be scheduled, how long it takes to prepare to apply the particular system used (for example how long it takes to apply the reinforcing mesh, etc.).  
           [0008]    In that time, due to heat or cold, the sealing strips can become “unstuck” to the paper and nailing flange, can wrinkle, and otherwise can provide a less than perfect seal. After the stucco is applied, water can sometimes enter the structure through this interface between the window and the stucco in a storm for example, by seeping around the sealing strips, or behind them if wrinkled or de-laminated from the paper or window. This is highly undesirable, as dry rot, mold spores, structural damage, discoloration of stucco or interior walls, etc. can occur. The leaking condition of the window may require the stucco around the window, the interior finish treatment, and sometimes even the structure around the window to be replaced. Likewise, the same generally applies to door openings, and other places in the structure, such as vents, etc. where something passes through the exterior treatment.  
           [0009]    Also, while stucco has been discussed thus far, the same problems, though they may be addressed slightly differently in each case, applies to exterior siding, brick, stone, and other treatments applied to the exterior. One solution is to additionally provide a metal or polymeric resin flashing to problem areas, with a similar object as is done in roofing, to provide for water management around the problem areas to minimize intrusion of water by directing it over or around such problem areas. Usually such a flashing, when provided, is applied above the opening, the object being to direct water out and around the opening. One difficulty with the prior solutions is that water can sometimes seep back under conventional flashing, especially where no sealant is provided between the flashing and the window, or a provided sealant has de-laminated due to age and hot/cold temperature cycling, for example. The result is the above-referenced recognized problems resulting from water intrusion.  
           [0010]    Another problem area is the interface between the chimney and the roof structure. Often a chimney-bonnet or a chimney cap type structure is used over the top of the chimney. However, such a chimney-bonnet does not always prevent rain from seeping into the gaps between the chimney and the roof structure. Such water entering the gaps results in the above-referenced recognized problems.  
           [0011]    Another problem area is the interface between a frame member and a cement foundation. Here, water from the roof runoff splashing up and against the structure, from melting snow, from ponding water if adequate drainage around the structure is not provided, etc. can work through unsealed material interfaces, and cracks that can open with time, and can seep into the framed walls and/or the basement or first floor of the structure (especially with slab on grade construction in the latter case). Providing for water management at the structure/foundation interface is therefore also critical.  
           [0012]    Likewise, at the eaves of a structure, water management has also been recognized as very important. If water can get behind the exterior wall treatment at the top, such as the eaves, then it can damage the whole wall structure, top to bottom. Various methods for sealing and otherwise waterproofing this area have been used throughout history. Likewise, at a junction of two exterior treatments water can sometimes seep into cracks and joints. For example, the situation mentioned above where brick may transition to stucco at some point up a wall, water management at the joint is problematic, and is as critical as that around openings, if for no other reason that there may be a great length of such a joint, even extending completely around a structure, providing increased opportunity for a crack to open, etc. and allow seepage of water into the structure.  
           [0013]    Current best practice is using window drip flashing along the top of the brick, and laying up the stucco over this. However water can still get behind this arrangement and into the structure, especially in the cases of melting snow and wind-driven rain or sleet.  
         SUMMARY OF THE INVENTION  
         [0014]    It has been recognized that further improvement in water management at critical areas such as those mentioned above will yield benefits of lower incidence of harmful mold spores, dry rot and other structural damage; decreased incidence of interior water damage such as unsightly stains, etc. Further, cost savings to constructors, who will have fewer costly repairs to new construction, and to homeowners, who will have less costly repairs after a builder s warranties have expired, will be realized by more reliably excluding water from the structure.  
           [0015]    The present invention is directed to a flashing system configured to reduce moisture intrusion at an opening extending through an exterior treatment of a building structure. The flashing system includes at least one flashing piece having a main flashing portion and a sealing flange. The main flashing portion is configured to extend outward a distance from a periphery of the opening of the building structure to provide an effective moisture barrier and configured to be positioned against a wall having the opening defined therein. The sealing flange of the at least one flashing piece includes a top sealing flange, a bottom sealing flange, a first side sealing flange and a second side sealing flange each configured to extend outward from the main flashing portion and is configured to be positioned adjacent a peripheral-opening-structure at a respective top periphery, bottom periphery, first side periphery and second side periphery of the opening.  
           [0016]    The flashing system also includes a first top tab and a second top tab. The first top tab configured to extend laterally from the first end of the top sealing flange and configured to extend partially over the first side sealing flange. The second top tab is configured to extend laterally from a second end of the top sealing flange and configured to extend partially over the second side sealing flange.  
           [0017]    In one aspect of the invention, the bottom sealing flange can include a first bottom tab and a second bottom tab each extending laterally from respective first and second ends of the bottom sealing flange. The first bottom tab can be configured to extend partially under the first side sealing flange and the second bottom tab can be configured to extend partially under the second side sealing flange. Likewise, the first side sealing flange can include a top tab and a bottom tab each extending laterally from a top end and a bottom end of the first side sealing flange. The top tab of said first side sealing flange can be configured to extend partially under the top sealing flange and the bottom tab of the first side sealing flange can be configured to extend partially over the bottom sealing flange. Similarly, the second side sealing flange can include a top tab and a bottom tab each extending laterally from a top end and a bottom end of the second side sealing flange. The top tab of the second side sealing flange can be configured to extend partially under the top sealing flange and the bottom tab of the second side sealing flange can be configured to extend partially over the bottom sealing flange.  
           [0018]    In still another aspect, each of the bottom sealing flange, the first side sealing flange and the second side sealing flange can include tabs extending from opposing ends thereof. Such tabs, in conjunction with the first top tab and the second top tab, can be configured to interconnect each of the bottom sealing flange, the first and second sealing flange, and the top sealing flange together.  
           [0019]    In another aspect of the invention, the flashing system can include a drip flange extending downwardly outward from a portion of the bottom sealing flange, and configured to direct moisture away from the wall below the opening extending through the exterior treatment of the building structure. The drip flange can include a folded-back portion wrapped around an under-side portion of the drip flange. The drip flange can include a downward extension extending from the folded-back portion, wherein the downward extension can be configured to be positioned against the wall below the opening extending through the exterior treatment of the building structure.  
           [0020]    In another aspect of the invention, the distance of the main flashing portion can extend from the opening between approximately four to eight inches. Such main flashing portion can include at least one laminate configured to extend thereover.  
           [0021]    In another aspect of the invention, a sealing flange extension extending substantially perpendicularly inward from each of the top sealing flange, the first side sealing flange and the second side sealing flange, wherein the sealing flange extension is configured to extend at least partially over the peripheral-opening-structure at the periphery of the opening.  
           [0022]    In still another aspect of the invention, the bottom sealing flange can be configured to extend outward beyond the peripheral-opening-structure at the periphery of the opening. Also, a downward extension can be included between an end of said sealing flange and said drip flange.  
           [0023]    In one embodiment, the at least one flashing piece can include a bottom flashing piece, a top flashing piece, a first side flashing piece and a second side flashing piece, each including a corresponding one of the main flashing portion and each configured to be positioned on the wall at a corresponding bottom side, top side, first side and second side of the opening extending through the exterior treatment of the building structure.  
           [0024]    In another embodiment, the at least one flashing piece can include the main flashing portion having the top sealing flange and the bottom sealing flange, a first side flashing piece and a second side flashing piece. The first side flashing piece can include a flashing portion and the first side sealing flange, wherein the flashing portion of the first side flashing piece can be configured to extend over a first portion of the main flashing portion. The second side flashing piece can include a flashing portion and the second side sealing flange, wherein the flashing portion of the second side flashing piece can be configured to extend over a second portion of the main flashing portion.  
           [0025]    Other features and advantages of the present invention will become apparent to those of ordinary skill in the art through consideration of the ensuing description, the accompanying drawings, and the appended claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]    [0026]FIG. 1 is an exploded perspective view, partially in cut-away, of a water management system in one embodiment of the invention, and adapted for a window, or doorframe, or other through-wall feature, a window being shown by way of example;  
         [0027]    [0027]FIG. 2 is a perspective view partially in section taken along line  2 - 2  in FIG. 1, and partially in cut-away, of a bottom flashing element of the embodiment shown in FIG. 1 illustrating features thereof in greater detail;  
         [0028]    [0028]FIG. 3 is a cross sectional view, taken along line  3 - 3  in FIG. 1, of a portion of the flashing system installed below the window of the embodiment shown in FIG. 1, an exterior finish below the window being shown in outline, and omitting representation of a sealant which can be located between the lower flashing element and the bottom of the window frame, and which would be pressed very thin and present as a line in this cross section view;  
         [0029]    [0029]FIG. 4 is a perspective view, partially in cut-away, partially in section taken along line  4 - 4  through any one of the two side and one top flashing pieces in FIG. 1;  
         [0030]    [0030]FIG. 5 is an enlarged view, taken at line  5 - 5  in FIG. 4, of a portion of that view showing further details;  
         [0031]    [0031]FIG. 6 is an enlarged view, taken at line  6 - 6  in FIG. 1, of a portion of the top flashing piece showing further detail and possible additional embodiments in outline;  
         [0032]    [0032]FIG. 7 is a perspective view of another embodiment integral in a window frame unit, where in the flashing is combined with the nail flange, and the drip flange is integrally connected to the bottom of the outer bottom of the window by molding or welding in a unitary construction or by attachment by adhesive or fasteners;  
         [0033]    [0033]FIG. 8 is an enlarged view, taken along line  8 - 8  in FIG. 7 of a bottom portion of the window frame of FIG. 7 showing additional details;  
         [0034]    [0034]FIG. 9 is a similar view as that of FIG. 8 of another embodiment wherein the drip flange is positioned back from the front of the window under the bottom, rather than flush with the front face of the frame;  
         [0035]    [0035]FIG. 10 is an exploded perspective view, partially in cut-away of another embodiment of the invention, additional variations being shown in outline, e.g. whether molded or folded, in the later case having seams shown in outline;  
         [0036]    [0036]FIG. 11 is a perspective exploded view of another embodiment of the invention similar to that shown in FIG. 10 showing one example of a cut and folded metal construction with additional pieces to be soldered, welded or otherwise sealingly attached, shown before (left side), and after (right side), attachment;  
         [0037]    [0037]FIG. 12 is a cross sectional view, taken along line  12 - 12  in FIG. 13, of another embodiment illustrating adaptation for use with certain exterior surface treatments, for example stone work, such as water management in a stonework to stucco interface;  
         [0038]    [0038]FIG. 13 is a perspective view, partially in section, partially in cut-away, illustrating an application of the flashing embodiment shown in FIG. 12;  
         [0039]    [0039]FIG. 14 is a cross sectional view, taken along line  14 - 14  in FIG. 15, illustrating adaptation for use with certain exterior surface treatments, for example brickwork, such as water management in a brickwork to stucco interface;  
         [0040]    [0040]FIG. 15 is a perspective view, partially in section, partially in cut-away, illustrating an application of the flashing embodiment shown in FIG. 14;  
         [0041]    [0041]FIG. 16 is a perspective view, partially in section, partially in cut-away, of another embodiment illustration of adaptation for use with a sloped top portion of certain exterior surface treatments, such as eliminating the need for fair raking in brick work, and how it can be integrated into a flashing system for transition to stucco or another exterior treatment, or directly with flashing around a roof at the eaves, gable(s), a pediment, etc.;  
         [0042]    [0042]FIG. 17 is a cross sectional view of an embodiment configured for water management at a structure wall/foundation interface incorporated in a structure having a brick exterior there;  
         [0043]    [0043]FIG. 18 is an enlarged cross sectional view, taken in the area of line  18 - 18  in FIG. 17;  
         [0044]    [0044]FIG. 19 is a cross sectional view of an embodiment configured for water management at a structure wall/foundation interface incorporated in a structure having a stucco exterior there;  
         [0045]    [0045]FIG. 20 is an enlarged cross sectional view, taken in the area of line  20 - 20  in FIG. 19;  
         [0046]    [0046]FIG. 21 is a cross sectional view, taken along line  21 - 21  in FIG. 22 of an embodiment configured for water management at a structure wall/roof eaves interface incorporated in a structure, the sheathing and roof truss of which is shown only in outline for relative position; and,  
         [0047]    [0047]FIG. 22 is a perspective view, partially in section, partially in cut-away, illustrating incorporation of the flashing shown in FIG. 21 in a roof eave, configured to both allow airflow and protect the structure from water intrusion at a top portion of the exterior wall. 
     
    
     DETAILED DESCRIPTION  
       [0048]    For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the exemplary embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the invention as illustrated herein, which would occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the invention.  
         [0049]    With reference to FIG. 1 of the drawing figures, which are given by way of example, and not by way of limitation, a flashing system  10  in one embodiment comprises metal or plastic flashing pieces  12 ,  13 ,  14 ,  15  which cooperate to form a water-tight seal around a window  16  in a wall structure  18 . Taking as an example the case of a stucco exterior treatment, though the invention will be applicable to other exterior treatments, such as stone, siding, brick, etc., frame members  19 ,  21 , cooperate with exterior sheathing  20 , such as exterior grade medium density fiberboard, plyboard or the like to form a wall which, receives the window  16 , either before, or after, an exterior waterproofing layer  22  (vapor barrier) is applied to the sheathing, as shown in FIG. 3. The waterproof layer can be, for example, tar paper, TYVEK or a suitable substitute, and is applied to the sheathing. Therefore a nailing flange  24  of the window can be inside or outside the paper  22 . In either case, the system in the illustrated embodiment is installed by first installing a bottom piece  12  underneath the bottom of the window. As well be appreciated with respect to FIGS. 2 and 3, this is to provide a seal below the window. This is by virtue of a seal between the bottom piece  12  and the window and the downwardly extending flashing portion  26 , and also to direct water coming off the bottom of the window, for example from weep holes  28 , and otherwise off the window, downwardly and outwardly by virtue of a drip flange  30  which extends downwardly for some length, usually between an ⅛″ and 1″, for example about ½″, and outwardly at an oblique deflection angle of about 30 degrees. This inclined portion extends for about ½″ to ¾″. This insures that water  32  drips down and away from the front face of the exterior treatment  34  (in this case stucco) and does not immediately contact it. Although the water may drip down free of the wall, or may be blown back into the wall by wind lower down in its fall, at least it is not a concentrated stream of water running off the window as would otherwise be the case. The drip flange acts to protect the stucco beneath the window  16  from deterioration due to excessive water exposure. As is well known, stucco is not entirely water-tight, and water can seep back underneath the window were it not for the bottom piece  12  thus configured. As can be seen, the “wing” portions  35  of bottom piece extend outwardly beyond the sides of the window for some distance  36 , commensurate with the depth of the flashing portion  26 . Typically, this distance will be between 4″ and 8″, for example about 6″. This outwardly extending wing portion  35  is present on both sides of the bottom piece  12  below the window.  
         [0050]    A bead of sealant (not shown) can be applied to the top of the bottom piece  12  or the bottom of the window before installing the bottom piece. This can be flattened and provide a continuous seal by pushing up the flashing piece against the bottom of the window. In another embodiment, a form strip can be provided along a top portion  37  of the flashing piece, this provides a seal by virtue of a restoring force of the foam causing it to fill the space when the bottom piece  12  is pushed up against the window. An adhesive foam can be used to stick to both the flashing and the window. For example, an adhesive foam tape strip can be applied to the top of the flashing, leaving a peel-back paper backing over the side of the tape that will stick to the bottom of the window until just before installation.  
         [0051]    Furthermore, when the bottom piece  12 , is cut, tabs  38  of varying length remain. Tabs  38  can be folded up around the bottom outer portion of the window  16 . While these tabs are optional there is little incremental cost to providing them as the metal would otherwise need to be removed in any event. In one embodiment a seal, such as the adhesive foam strip described above, can be provided on these tabs also. Tabs  38  provide additional water resistance around the corner regions formed by flashing pieces  12 ,  13 ,  14  and  15 .  
         [0052]    In one embodiment, the flashing piece  12  is attached by staples or other fasteners directly through the flashing piece. In another embodiment, a laminate sealing product, sometimes referred to as Vitchathyne, which is a laminate  40  of a polymeric sheet and bituminous sealant, is applied over the flashing and then staples or other fasteners are driven through the vitchathyne and the laminate and the paper  22 , into the sheathing  20 . This way, the sealant of the laminate is drawn in to seal the staple holes made in the flashing piece  12 .  
         [0053]    Next, two side flashing pieces,  13 ,  14  are set up against the sides of the window  16 . These pieces, as can more clearly be seen with reference to FIGS. 4 and 5, cooperate with the window  16  to provide a water-tight seal around the window. A sealing flange  42 , extends outward and then at a right angle across the front of the window from the flashing portion  26 , and doubles back on itself behind to provide a smooth edge  44  and increased strength. In one embodiment a foam seal strip  46  can be provided. The foam seal can be for example, a foam tape with adhesive on both sides which adheres to a turned back portion  48  of the sealing flange, and also to a front portion  50  of the window  16 .  
         [0054]    These side pieces also have portions of the outwardly extending flange  26  which extend above and below the window, which for convenient reference will also be called wing portions  35 . These overlap the similar wing portions  35  of the bottom sealing flange member  12 , which has previously been attached. They also extend above the window  16  a distance  52  commensurate with the width of a top flashing piece,  15  to be discussed. As will be appreciated, that dimension,  52 , can be the same, greater, or lesser, than the width  36  of the side pieces  13  and  14 . Also, the width  52  can be the same as, or different than, the distance  36  of the side members  13  or  14 , and can be the same lesser or greater than a thickness  52  of the bottom member  12 . As will be appreciated, in the illustrated embodiment all these dimensions are the same and the pieces overlap by the same amount.  
         [0055]    As discussed before in connection with the bottom piece  12 , the sealing flanges can have folding tab portions  38 , which fold under and over the outwardly extending portion of the window  16  and cooperate with the other flashing members to provide a water-tight seal. As will be appreciated, the bottom tab portions  38  on the side flashing pieces  13  and  14  will fold under the window and also behind the drip flange  30 , up against a bottom inner portion ( 54  in FIG. 3) of the bottom flashing member  12 .  
         [0056]    As discussed before the flashing pieces are attached by staples, or other fasteners. Vitchathyne laminate sealing strips  56  can also be used in one embodiment, as described above.  
         [0057]    Completing the system, the top flashing piece  15  is fit over the top of the window  16 , and wing portions  35  of this top piece overlap the upwardly extending wing portions of the side pieces  13  and  14 . The sealing flange  42  of the top piece extends down over the outwardly extending portion of the window, and contacts the front face  50  thereof in a sealing engagement, as before described with reference to the side pieces. The top piece can be further appreciated with reference to FIG. 6, where different, alternate, embodiments are shown in outline form. In one embodiment the sealing flange  42  is trimmed back at an angle  58  which can be for example 45 degrees. Likewise, the tab portion  38 , which folds down, (if provided) can be cut back by an angle  60  from the front, to hide the front edge under stucco (not shown) to be applied. For example, this angle  60  can be between 5 and 15 degrees in the illustrated embodiment. In another embodiment the tab  38  can be brought downward commensurate with a front portion of the sealing flange  42  and then cut back at another angle  62 , for example 45 degrees. In another embodiment the top can be dressed by cutting back the tab at an angle  64  from a top front corner  66 . For example, that angle can be 45 degrees. As with the side pieces, the sealing flange can be provided with a further seal  46  which can again be a double-adhesive form tape strip. Such tape strips are widely commercially available.  
         [0058]    A further laminate strip sealing  68  can be applied over the flashing piece  15  to seal any holes made by staples  70  or other fasteners driven through the flashing, as described above.  
         [0059]    Furthermore, as mentioned the flashing can be made of metal or plastic. As will be appreciated, in this and all the embodiments described herein, the metal can be aluminium, tin, sheet metals of other alloys, and the plastic can be a polymeric resin such as PVC, and other substances which are suitable in terms of long term stability, resistance to UV breakdown, etc. Composites of polymeric resins and fiberous materials, metal and plastic laminated materials, and other suitable materials which can be used for flashings and can be configured as shown herein are contemplated for use in embodiments disclosed herein.  
         [0060]    With reference now to FIGS. 7, 8 and  9 , in another embodiment the invention can be implemented by incorporating salient features directly in the window  72 . For example, this can be done by molding the features in a window frame formed of a polymeric resin. The sealing flashing described above can be provided by extending a nailing flange outward to form a sealing flange  74  around the outer periphery of the window. For example, this flange could extend at least 6″ rather than the 1″ or 2″ nailing flange commonly provided. Again, the reason for extending this flange is to prevent water leaking back into the structure from the joint between the stucco and the window  72  at a forwardly extending portion  76  which comes outward through the exterior treatment. Again, for sake of convenience, we will discuss this embodiment in connection with a stucco exterior treatment, but as will be appreciated, the same is applicable to other exterior treatments such as the brick and siding mentioned. A bottom drip flange  78 , again extending downwardly some distance from an ⅛″ to a ½″ to as much as ¾″, for example, and then outward at an oblique deflection angle  80  of between about 15 and 45 degrees (and in the illustrated example about 30 degrees) is provided. This drip flange portion can be molded integrally, or can be afterwards attached by heat welding, solvent welding, ultrasonic welding, or otherwise as is known in the art to join pieces of polymeric resin.  
         [0061]    With reference particularly to the embodiment shown in FIGS. 8 and 9, in one embodiment the drip flange  78  can extend downwardly from an outward face  82  of the window, and in another embodiment it can be set back to depend downwardly from a bottom portion  84  of the frontwardly projecting portion  76  of the window  72 . As will be appreciated, which of the embodiments that of FIG. 8 or FIG. 9, is provided, depends on many factors, such as the exterior treatment to be used, the distance which the forwardly extending portion  76  extends outward from the sealing flange portion  74 . In another example, the embodiment illustrated in FIG. 8 could be used with a stucco pop-out, whereas that of FIG. 9 could be used without a stucco pop out.  
         [0062]    With reference to FIG. 10, in another embodiment the water management system comprises a unitary flashing piece  90 , which can be formed of polymeric resin, for example by a molding process. In this embodiment, the flashing piece is sized to fit over a window  92  previously attached to a wall  94 . The unitary piece is substantially the same as the four-piece system, but is made specifically with the same dimensions as the window  92  to cooperate therewith to provide the same advantages for that window specifically. A sealing strip  96 , for example the adhesive foam tape described above, is attached to the inner surface  98  of the unitary flashing element  90 , to provide the configuration described above in connection with the four-piece unit. In one embodiment, a bead of sealant (not shown) is applied between the bottom of the window  92  and the bottom  100  of the opening in the unitary flashing piece. In another embodiment a foam strip (without adhesive on one side) can be used. The unitary flashing piece of the water management system in this embodiment can be attached by fasteners, such as staples, as described above, and also in another embodiment a sealant strip can be used to seal the holes through a flashing portion  102 , as described above.  
         [0063]    In this embodiment also, a lower drip flange  104  is provided, substantially as described above. In the polymeric resin embodiment, the drip flange can be molded unitary with the rest of the unit, or can be added by heat welding, solvent welding, ultrasonic welding, etc.  
         [0064]    In another embodiment, the unitary flashing unit  106  illustrated in FIG. 11 is formed of a metal material. In the illustrated embodiment, the unit is formed by cutting out the center, and folding the bottom drip flange  108  and a top window enclosing flange  110  from the unitary sheet. Side portions  112 ,  114  are formed of separate fold and metal pieces, which are pushed through the opening from behind, and welded, brazed, or are otherwise sealingly attached to the rest of the unitary sheet  106  at least along an attachment flange  116  provided on each metal piece. A portion  118  of the upper window and casing portion  110  is folded around behind the two side extension pieces  116  provided  112 ,  114 , and is folded back on itself to interlock. This configuration provides a dressed appearance, similar to that which is provided by the embodiment using four-pieces described above, when completed. As with an added embodiment, in this one also a sealant can be used between the piece  106 , and the window  92  such as the adhesive foam tape described above, for example.  
         [0065]    With reference now to FIGS. 12 and 13, in the case where the exterior treatment comprises stone work  119  a flashing  120  can be configured to direct moisture outward and over the stone work, by means of a drip flange  122  similar to that described above. Water  124  is directed outward to fall away from the face of the stone work. In one embodiment a portion  126  which extends from the (covered) face of the sheathing  20  outward over the top of the stone work is inclined at a slight angle  128  to lessen the tendency for water to pool there. Stucco  130  another exterior treatment may be applied over the flashing  120  but other exterior treatments could also be used, for example siding, on a brick, board and batten, etc.  
         [0066]    With reference now to FIGS. 14 and 15, in another embodiment a flashing strip  132  can be configured to fit over top a brick exterior treatment  134  at an upper edge, again, to deflect water  136  outward and away from the brick work. This embodiment, the drip flange  138  can further comprise a downwardly extending flange portion  140  which provides greater depth of the drip flange downward from the top of the brick work  134 . As will be appreciated, this feature can be deleted in another embodiment. A portion  142  of the flashing adjacent a top of the brick work can be inclined at a first smaller angle  143 , while a second portion  144  is disposed at a second, steeper angle  145 . Again these features are provided to discourage water ponding within an exterior treatment, such as stucco  146 , siding, etc.; but, rather runs off.  
         [0067]    Moreover, with both the embodiments illustrated in FIGS. 12 through 15, if a brick work, for example of a different type, size, etc. is used above the flashing, the sloping portions ( 126  in FIG. 12, 142 and  144  in FIG. 14) support a back edge (not shown) of a brick, and the widening gap, as it extends outward, will be filled with mortar, and is usually provided with weep holes. In any case, it has been found that the sloping confirmation helps the bottom portion of a brick exterior treatment dry more quickly, as the water moves outwardly and downwardly along the inclined portion of the flashing  120 ,  132 .  
         [0068]    With reference now to FIG. 16 in another embodiment, similar to that discussed above and illustrated in FIGS. 14 and 15, a flashing strip  150  is configured to fit over an inclined portion  152  of an upper portion of a brick work exterior treatment  154 . A drip flange  156  and downwardly depending portion  158  below that, are made wide enough to cover the stepping set backs of the bricks of the exterior treatment  154 , and can be, for example, 3″ or more in total depth  160  from a sloping portion  162  which extends outward and downward from the sheathing  20  of the structure. This flashing  150  can be configured to form a set back area, and be exposed between the top of the brick  154  and the eaves  164 , in which case flashing will be exposed, or to provide a transition to stucco  166  extending between the brick work and structure above, such as the eaves  164 . In the former case, the flashing is tucked behind a structure, such as additional flashing  168  covering a roof overhang. Such additional structure may be attached to the flashing  150  and the sheathing  20  in an overlapping portion  170 , for example by staples, screws, nails, or other fasteners.  
         [0069]    Like the embodiments illustrated in FIGS. 12 through 15, the configuration shown in FIG. 16 assures that water will be deflected outward and over, and away from the brick exterior treatment  154 . It may be used to obtain architectural effects, for example it may fill an aesthetic function, as well as a practical one of keeping water out of a top portion of a wall of a structure. With reference now to FIGS. 17 and 18, another problematic area, as mentioned, is the interface between a foundation  172 , and an exterior treatment, for example brick work  174 . The flashing  176  attached to the sheathing  20  the structure extends underneath the brick work, and over top the foundation, to extend down the front of the foundation some distance  178 , for example between ½ and ½″. A drip flange  180  which can be folded back, as described above, is provided to direct water  182  out and over the remainder the outside of the foundation  172  which can be covered by a finished coat  184  for example.  
         [0070]    The flashing can be provided with a sloping portion  186  extending between the sheathing and outside front corner  188  of the foundation. If a brick exterior treatment is to be supported, a grout  190  is laid down on top of the foundation before the flashing is applied, to provide support for the weight of the exterior brick work when set up. When the brick work  174  is placed on top of the flashing  176 , mortar  192  fills the outward widening space between a back bottom corner  194  of the bottom course of bricks, and the front of the exterior. Again, this provides a sloping surface to direct water outward and away from the bottom of the brick exterior treatment. As will be appreciated, weep holes are periodically provided in the bottom of brick work, and this sloping surface will provide a sloping weep hole as well.  
         [0071]    With reference now to FIGS. 19 and 20, another embodiment, a flashing can be configured to perform a similar function at an interface between a foundation  196  and a stucco exterior treatment  198  at the bottom portion of an exterior wall  200 . In this case, a flashing  202  extends over the lower portion of the exterior sheathing  20 , and then deflects backwards and under the exterior sheathing to contact the foundation wall, extends downward for some portion  204  between ½″ and 1½″, for example, and then comprises a drip flange  206 , to direct water  208  outwardly and over an exterior finish coat  210  applied to the foundation  196 . The drip flange can be doubled back to form a second slanting portion  212  as described above. The Flashing in one embodiment is configured to extend down about 3 inches from the top of the foundation wall. This distance can be made shorter, or longer, depending on the particular application and any aesthetic or functional architectural considerations dictating a different distance.  
         [0072]    A vapor barrier  213  applied to the sheathing is made to overlap the flashing  202  so that water is prevented from running down the wall behind the flashing. As with all the embodiments, the exterior finish below the drip flange can be pushed up under it, to prevent water getting between the drip flange and the exterior finish coat below it. For example, if the foundation is plastered, then the plaster is applied under a bottom drip flange  206  to seal the opening to prevent water climbing up behind the flashing by capillary action.  
         [0073]    A “J” strip  214  is attached to the flashing  202  in the illustrated embodiment. The J strip is provided with weep holes  216  to accommodate moisture  218  escaping from the bottom of the stucco exterior treatment  198 . The J channel, is conventional, and known in the art.  
         [0074]    With both the embodiments illustrated in FIGS. 17 and 18, as well as that of  19  and  20 , the height of the flashing, or how far it goes up the exterior wall sheathing  20  of the structure depends on conditions in a particular application. For example, it can extend up a first height  220  in either case, for example about 6″, or 8″, or so, or, if snow is expected to lay against the structure, or if frequent floods are expected, a taller flange, extending up to a second height  222 , for example 18″, can be provided to keep moisture from entering the structure at the interface between the foundation ( 172  in FIG. 17, 196 in FIG. 19), and the structure.  
         [0075]    Turning now to FIGS. 21 and 22, at an upper portion of an exterior treatment, such as stucco  224  where it approaches the eaves  226  of the structure  228 , is particularly important to keep water from entering the structure, to get behind the exterior treatment. This goal is complicated by the fact that venting, to provide for air flow  230  through vents  232 , and into the roof of the structure  228  for cooling purposes (as is known, vents are provided near the top of the roof for this air to escape through) once it has absorbed heat from the roof  234 . As will be appreciated, this helps the roofing materials used to last longer.  
         [0076]    A top protective flashing piece  236  which accommodates air flow, is provided in this embodiment to extend from the exterior sheathing  20  down outward and over an exterior treatment, such as the stucco  224  and down the face thereof for some distance. This distance can be relatively short e.g. first length down to a bottom edge  238  or a longer downward distance to a bottom edge  240  and in either case, a drip flange  242  can be provided as described above. As will be appreciated, it is more important the farther down the flange bottom  240  is, exposing it to wind driven water for example. A curving portion  244  extending upward and outward from the exterior sheathing  20  of the structure, and attaching to bottom of the roof trusses  246  provides protection for the top of the exterior treatment from any moisture which may be driven through the vents  232  in the eaves  226 . This can happen, for example, when strong winds drive rain or snow against the side of the structure  228  and at the same time creating a negative pressure at the roof top vents (not shown) which tends to draw the air through the vents  232 . Any such moisture, in this embodiment is prevented from entering the structure itself, by the curving portion  244 , and is directed back downward and outward and over the exterior treatment  224  as in the embodiments described above. As can be appreciated, this provides an extra measure of security that moisture will not enter the structure at the top of the exterior treatment, at the interface between the roof  234  and walls of the structure. An outward edge  248  can be turned back in one embodiment to provide increased stiffness of the outer edge of the flashing piece  236 .  
         [0077]    As will be appreciated, the flashing system described herein provides improved water tightness of structures, and particularly prevents water ingress at critical points, such as joints and interfaces between two differing exterior treatments, at the roof line, and at the foundation, structure wall interface. Moreover, the system in accordance with the invention can be implemented with minimal additional cost, and the benefit of lower maintenance cost over the life of the structure, and the prevention of water damage which could otherwise occur providing substantial cost savings overall. Further, the system as illustrated herein mitigates the formation of mold, mildew, mold and mildew, and the like, which can be harmful to the health of the occupants of the structure.  
         [0078]    While several embodiments of the invention have been illustrated and described, it will be appreciated that various modifications can be made, without departing from the spirit and scope of the invention.