Patent Publication Number: US-10774537-B2

Title: Double coverage roof wall flashing with cavity

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Applications Nos. 65/659,757, filed Apr. 19, 2018, and 60/643,335, filed Mar. 15, 2018. Each of these applications is herein incorporated by reference, in its entirety, for all purposes. 
    
    
     FIELD OF THE INVENTION 
     The invention relates roofing, and, more particularly, to flashing used in roof applications. 
     BACKGROUND OF THE INVENTION 
     It is commonplace to install metal flashing where a wall intersects the roof plane. In sloped roofing applications, it is typical for the roof to encounter a wall, such as a dormer. In flat roof installations, many roof systems terminate at a parapet, roof protrusion, or wall. 
     The roofing industry has typically frowned on second layer roof applications, due to the inability of the next cover roofing system to tie into existing flashing when encountering a wall. The problem is further exacerbated when a wall cover material, such as stucco, siding, or other wall cover, extends over the top edge of the existing wall flashing. To replace the existing wall flashing, the wall cover material needs to be removed and reinstalled or replaced. These steps add time and expense to roof replacement. 
     Despite the roofing industry&#39;s reservations regarding second layer roofing applications, the use and encouragement of second layer roof applications remains desirable, primarily due to cost and environmental impact benefits. Moreover, there is a substantial movement towards shingle recycling and keeping the existing shingles on the roof through another roofing cycle, as more communities come on board with shingle recycling efforts. Suffice it to say that, second layer applications are cleaner, while saving the owner money and the roofing contractor time. 
     What is needed, therefore, is flashing that can be used in second layer roofing applications that is able to tie into existing flashings when encountering a wall, without removal and/or replacement of the existing flashing. 
     SUMMARY OF THE INVENTION 
     A roof wall flashing comprising a cavity suitable for second layer recoverability that is built into the flashing itself allows for tying into existing flashing when encountering a wall without removal and/or replacement of existing flashing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a double coverage roof wall flashing comprising a cavity and ledge, configured in accordance with the embodiments of the present invention; and 
         FIG. 2  is a double coverage roof wall flashing with a cavity and closed hem, configured in accordance with embodiments of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     One embodiment of the present invention, as shown in  FIG. 1 , provides a base flashing  101  designed to sit on a roof surface and a wall flashing  109  designed to abut a wall the intersects the plane of a roof. In the case of the roof surface and wall to be flashed being perpendicular to one another, the interior angle  102  created between the base flashing  101  and wall flashing  109  is approximately 90 degrees. Otherwise the base flashing  101  and wall flashing may be bent to match the angle created by the roof and wall to be flashed. 
     The wall flashing  109  is designed to extend up a vertical wall before returning onto itself, forming a living hinge  110  while also creating a cavity  103 . The inner portion of the hinge  111  is further bent approximately 90 degrees  104  away from the wall flashing  109 , resulting in it extending away from the wall flashing  109  perpendicularly, before being folded back on itself, resulting in a closed hem  106  that forms a ledge  105 . The material forming the ledge  105  is then further bent upwards at approximately a 90 degree angle  107  and, after extending upwards until it is substantially level with the top portion of wall flashing  109 , is angled slightly rearwards until it meets the plane defined by the wall flashing  109  and is subsequently angled once again to remain substantially within the plane defined by the wall flashing  109 , forming upper wall flashing. 
     The ledge  105  created by the closed hem  106  may, in embodiments, be biased towards the wall through a spring effect or hinge, which can be created by virtue of the flashing&#39;s construction, through the use of special materials and/or alloys, and in other ways, as would be known to those of ordinary skill in the art. 
     In embodiments, the ledge  105  may be formed above or below a topmost portion of the wall flashing  109 . The ledge  105  may also be bent further from the roof plane than 90 degrees, depending on the siding being installed, so as to further compress the cavity  103 , due to the weight of the siding material installed. In addition, the ledge  105  may be designed such that the weight of the siding causes it to become parallel to the roof surface following installation. The ledge  105  may also be bent closer to the roof plane to provide for water discharge off of the ledge. 
     The installation of siding, stucco or the other exterior wall products onto the ledge allows the hinge  110  of the flashing to act like a spring by compressing the cavity  103  thereby further securing flashings installed at the interface between the wall flashing  109  and the inner portion of the hinge  111 , which form the cavity  103 . 
     In another embodiment of the present invention, the ledge is eliminated, but the cavity  201  remains and is built into the flashing itself, allowing for second layer recoverability. In this embodiment, the base flashing  202  extends onto the roof surface and is bent at a 90 degree angle  203 , becoming wall flashing  204 . In other embodiments, the base flashing  202  and wall flashing  204  may be bent to match the angle created by the roof and wall to be flashed. The wall flashing  204  then extends upwards, in use along a vertical wall, before doubling back onto itself, towards the base flashing  202 , creating a hinge  209  and a cavity  201 . At a certain point, the inner portion of the hinge, which could also be construed as the outer portion of the cavity, again doubles back onto itself, forming a vertically-oriented closed hem  205  that is substantially parallel to the wall flashing  204 . Regarding the material forming the closed hem  205 , after extending upwards until it is substantially level with a top portion of wall flashing  204 , it is then angled slightly rearwards until it meets the plane defined by the wall flashing  204  and is subsequently angled once again to remain substantially within the plane by the wall flashing  109 , forming upper wall flashing  207 . 
     The point  206  of the closed hem  205  creates a continuous straight line  208  that siding materials can follow, proving for a clean, finished siding starting point and edge. 
     The cavity of each embodiment ( 103  and  201 ) provides protection to the top edge of future flashings. After completion of the second layer roof, the closed hem  205  of the embodiment shown in  FIG. 2  may be fastened to a wall, securing second layer flashing installed during a roofing repair or re-roofing process. 
     In embodiments, the flashing is tapered step flashing that accounts for the width of the shingles to be used, thereby maintaining a straight profile of the ledge  105 , closed hem  106 , the point  206 , and the cavity ( 103  and  201 ). The flashing with a cavity ( 103  and  201 ) may be fabricated to any length that may be needed or required by local building codes. 
     For sloped roof applications, the step flashing with cavity or continuous flashing with cavity should be installed commencing towards the eave and working towards the ridge for proper overlap and watershed. On flat roof applications, the starting location of the installation of the flashing is not generally important, however, on flat roof applications, a sealant should be installed at the overlap of the wall flashing ( 204  and  207 ) sections and the sections may be secured to the wall through the closed hem  205 . 
     In embodiments, the double coverage flashing is installed along a wall during an initial roofing process. While the benefit of the cavity ( 103  and  201 ) may not be apparent during the initial roofing, it will become evident when the roof needs to be replaced or serviced. More specifically, if repair or retrofitting of an existing roofing system constructed in accordance with such embodiments is required, it now becomes possible, without removing existing wall cover material and roofing. 
     Additionally, a roofing underlayment may be installed along the roof surface and up the vertical incline, followed by the disclosed double coverage flashing. At such a time when a second layer roof is installed, step flashing or wall flashing may then be inserted into the cavity ( 103  and  201 ). 
     Furthermore, the joining of one section of flashing to the next using a notch is important to ensure a continuous cavity is formed therebetween. To achieve such fitment, the closed hem ( 106  and  205 ) of embodiments may be notched when joining one section to the next. More specifically, the closed hem ( 106  and  205 ) disclosed herein may be notched to provide for a seamless look, metal overlap, and to expose the cavity ( 103  and  206 ) without interference of an overlap, which would prevent any subsequent flashing from being installed seamlessly. 
     In embodiments, the notch is made on-site using tin snips, while, in other embodiments, the notch may be formed during the manufacturing process. 
     The placement of the notch is very important to achieving the proper overlap. The notched section of the flashing may be the top side facing towards the ridge on sloped roof applications. As such, in  FIG. 1 , the material removed to provide for proper overlap on metal sections would be as follows: remove metal on the bottom of closed hem  106  and metal from the inner portion of the hinge  111  to create a notch. The disclosure as depicted in  FIG. 2  should have the following material removed from metal sections thereof to provide for proper overlap: remove metal from the closed hem  205  closest to the wall flashing  204  from the point  206  to the hinge  210  and along the straight line  208 . While these locations are preferred, others may be used, as would be known to one of ordinary skill in the art. 
     In embodiments, the flashing is folded or gaped at the time of fabrication. The notch or fold, including expansion or gaping of metal sections via the use of specialty machinery, permits for the elimination of a notch and allows sections of the flashing disclosed herein to connect in a seamless manner. 
     Furthermore the flashing disclosed herein, in embodiments, is fabricated without the base flashing ( 101  and  202 ). Using such embodiments, the flashing may be installed onto custom fabricated or stock flashings as an additional piece, thereby providing for the future benefits of the cavity without changing the way systems are installed today. 
     The flashing disclosed herein is, most preferably, fabricated using a metal break of roll former, although other methods could be used, as would be known to one of ordinary skill in the art. The source material, typically metal, may be obtained in flat sheets or in roll form and be slit to the desired width prior to fabrication. 
     Materials, especially metals, are offered in a variety of gauges and mils, depending on local codes and performance requirements. The dimensions of the gap and the fabricated widths can vary from site to site, depending on the roofing system being installed and site conditions discovered prior to fabrication. 
     The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.