Patent Publication Number: US-8522508-B1

Title: Flashing support cant for a wall assembly and associated method

Description:
This claims the benefit of U.S. Provisional Patent Application Ser. No. 61/310,346, filed Mar. 4, 2010, and hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to water management systems for reducing water intrusion in structures. More specifically, the invention relates to such systems and configurations for above grade installation in wall assemblies. 
     Fungus and other molds having known health risks associated with them have been found growing within the walls of homes and buildings. Such molds can, and have, caused a recognized and serious health threat to home owners and building occupants. The growth of such molds can be facilitated by moisture seeping within the walls of homes and buildings. Conventionally, keeping moisture out of human-built structures has been an ongoing goal. Since mold spores have been found to be a serious health risk of late, due to increased incidence of moisture ingress in newer construction systems, preventing moisture from entering the walls of homes and buildings is considered much more serious and widespread concern than it has previously. 
     Wherever changes in wall planes exist, for example where there is a vertical to horizontal transition or a gap between wall components, supporting a membrane flashing at the transition or gaps has been mostly ignored by the associated trades. The areas where the walls of a building meet the foundation or a ledge, particularly in wood frame construction and the gaps between walls and fixtures, have been recognized as areas where water can enter unsupported membrane flashing gaps and therefore fail, because a construction joint of some type typically is provided there. For these and other reasons, the problem of moisture ingress is well recognized in the trades and in the field of architectural design. 
     The common solution for this problem is to install unsupported membrane flashing. However, this solution is costly because it is labor intensive. Further, if the flashing is not properly installed, such as by a careless or unskilled worker, water can leak at a sagged and failed flashing and into the open upper end of the frame member. 
     One identified problem is where there would be a negative pitch back toward the interior side of the flashing assembly caused by construction irregularities. Currently a cant is typically formed with materials that are mixed, applied and shaped, and then harden to support a membrane. While this method is used extensively below grade, the trades involved with installing flashing above grade often dispense with the mixed version of the cant in favor of none at all because of timing sensitivity in completing the installation and construction. 
     Thus, there is a need for a system that supports flashing at changes in wall planes and between gaps in materials where the solution is not labor intensive and can be easily and effectively installed by unskilled labor. 
     SUMMARY OF THE INVENTION 
     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 builders, who will have fewer costly repairs to new construction, and to homeowners, who will have less costly repairs after a builder&#39;s warranties have expired, will be realized by more reliably excluding water from the structure. 
     This invention addresses these and other problems in the art. In various embodiments, this invention is designed to create a cant or sloped plane for water management at the transition of vertical to horizontal components in a wall and bridging gaps between wall components to maintain the directional flow of water from the wall assembly. 
     In one embodiment, this invention is a cant member made from a corrugated metal or polypropylene sheet that has eight slits or scores across the front face and two slits or scores across the back face of the sheet that are parallel with the corrugations. The slits allow for bending of the member at a number of selected, predetermined locations. The back or inner face of the member has adhesive strips, covered with a release sheet, for adhesion of the member to the related substrate. The invention can be utilized in a number of different installation environments. As used herein, a cant member is a member having an inclination from a vertical or horizontal plane such as a sloped, slated, tilted or oblique member. 
     In various embodiments, the cant member is metal or polypropylene which will be preformed into 45-degree angle between a upper portion and an adjacent 3-inch section. It is anticipated the 3-inch section of the metal piece will be corrugated the same as a polypropylene piece in an alternate embodiment. This will provide a similar bending ease along the corrugations in the metal as with the polypropylene version. 
     The method of attachment for the cant member is, in one embodiment, a peel and stick adhesive or fasteners suitable for attachment to the substrate. The method of attachment will hold the cant member in place long enough to be covered by a membrane flashing. 
     Overall, the benefits to a user of this invention include a lower possibility of a negative pitch, and to keep water moving in an outward direction from the structure, and to support an otherwise weak membrane at a gap. An unsupported membrane flashing will fail over time. Additionally, the cant member of this invention can be rotated to accommodate a variety of different applications and as such simplifies construction and purchasing. 
     In various embodiments, this invention includes a wall assembly having an inner generally vertical wall having a wall face, an outer generally vertical wall confronting and being spaced from the wall face, and a generally horizontal ledge extending perpendicularly to and between the inner and outer walls. A cant member is installed on the wall assembly and has an inner wall or upper portion, a ledge or lower portion and a cant portion intermediate the upper and lower portions. The inner wall upper portion is juxtaposed in face-to-face relation and adhered or fixed to the wall face and the lower portion is juxtaposed and adhered or fixed in face-to-face relation to the ledge with the cant portion extending between the upper and lower portions such that the cant member may support a flashing member mounted to direct moisture toward the exterior wall and away from the wall assembly. 
     The invention also extends to a cant member as described in various embodiments herein as well as a method of constructing a wall assembly and the resulting wall assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of one environment in a cavity wall in which this invention may be used; 
         FIG. 2  is a front plan view of one embodiment of a cant member according to this invention; 
         FIG. 2A  is a perspective view of the cant member of  FIG. 2  bent into an exemplary installation configuration; 
         FIG. 3  is a perspective view of a cant member being installed onto an exemplary installation similar to that of  FIG. 1  under construction; and 
         FIG. 4  is a perspective of a cant member installed onto a ledge of a cavity wall installation according to another embodiment of this invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1 , an exemplary fixture installation  10  in a wall assembly  12  is shown. The exemplary fixture installation  10  includes a perimeter window frame  14 , one or more window panes  16 , and a window opening  18  in the wall defined by a pair of jambs  20  and a header  22  above and a sill  24  below the window frame  14 . Although one example of a window installation and a wall assembly  12  is shown in  FIG. 1 , this invention is readily applicable for a variety of other construction wall environments, including, but not limited to, door installations, installations including a transition of the wall assembly from vertical to horizontal planes and bridging gaps between vertical wall components. 
     As shown more clearly in  FIGS. 3-4 , one embodiment of the wall assembly  12  for the exterior of a building is comprised of an exterior wall of masonry or brick veneer  26  and an interior wall  28 . The brick veneer exterior wall  26  is constructed from a plurality of bricks or blocks  30  arranged in a vertical pattern. Each brick  30  is of a substantially rectangular shape having a uniform length, height and depth. The brick veneer  26  is built up by placing one layer of bricks  30  over another layer, with the upper layer vertically offset from the lower layer by a distance of approximately one-half the length of a brick  30 . Thus, as shown in  FIGS. 1 and 3 , a brick  30  on one layer is positioned directly over the space between two bricks  30  on the layer immediately beneath it. The spaces between adjacent bricks  30  and between adjacent layers of bricks are filled with mortar  32 . Alternatively, the veneer  26  may be stone, stucco or other components. 
     The interior wall  28  includes wood framing studs  34 , dry wall, plywood or the like  36 , and an outer sheathing material (not shown). Other materials may be used as is well known in the art. For example, a liner board (not shown) as disclosed in U.S. Pat. No. 7,421,826, issued Sep. 9, 2008 and hereby incorporated by reference, may be used on the interior wall  28 . In any event, the wall assembly  12  is constructed so that there is a small cavity or airspace A between the back side of the exterior wall  26  and a wall face  38  of the interior wall  28  confronting the outer wall  26 . The airspace A between the back side of the outer wall  26  and the wall face  38  of the interior wall  28  is usually at least about one to two inches deep, although the exact dimension may vary depending upon the nature of the construction. 
     A first embodiment of a cant member  40  is shown in  FIG. 2  and as installed in the wall assembly  10  of  FIG. 3  to provide a proper transition from the wall  12  to a fixture, one example of which is the window frame  14 . The cant member  40  is installed at the header  22  of the fixture opening  18  in cooperation with the corresponding portions of the fixture frame  14  to provide a transition from the vertical wall  28  to a ledge. As shown in  FIG. 3 , a steel or other material angle member  42  is typically provided at the header  22  above the frame  14  adjacent the interior wall  28  and extending along the outer wall face  38  of the interior wall  28 . The angle member  42  has a horizontal portion  44  extending forwardly from the interior wall  28  to form the header  22  and a vertical portion  46  forms one embodiment of a ledge and extending upwardly along the wall face  38 . The vertical portion  46  is typically spaced from the interior wall  28 . A drip edge  48  is typically positioned distally on the horizontal portion  44  to extend forwardly at its terminal edge of the exterior wall  26 . 
     In one embodiment as shown in  FIGS. 2-2A , the cant member  40  of this invention is a corrugated metal or polypropylene sheet with one or more adhesive layers  50 ,  52  on a back, inner face  54  thereof that are covered with separate silicone-faced release layers  56 ,  58 . The cant member  40  may have a thickness of 2 mM (85 mil) and an indeterminate length so that it can be cut to length to fit the installation requirements. The embodiment of the cant member  40  shown in  FIGS. 2-2A  is of indeterminate length as shown by the broken lines in those drawings. In one embodiment, the width of the cant member  40  is approximately five inches and the width of the upper portion  62  is approximately three inches and the widths of the cant and lower portions  66 ,  64  are approximately one inch each. The cant member  40  will be cut to length as required for the desired wall assembly  12  installation. Where more than one piece of the cant member  40  is needed, the ends of adjacent pieces can be cut to complimentary, mating configurations, if needed, and the ends of those pieces butt together to form the cant installation. While not shown herein for clarity, various flashing members may be mounted on top of the cant member  40  in practice and the cant portion  66  provides a stable support for such flashing members at the transition region from the interior wall  28  to the ledge in the form of a vertical portion  46  ( FIG. 3 ) or a horizontal ledge  22   a  ( FIG. 4 ). 
     The cant member  40  according to the shown embodiment includes an outer face  60  spaced from and generally parallel with the inner face  54 . The cant member  40  has a number of spaced membranes (not shown) extending between the inner and outer faces  54 ,  60  and forming a number of corrugations extending longitudinally along a length of the cant member  40 . The inner face  54  of the cant member  40  is adapted to confront and be juxtaposed in face-to-face relation with the various components of the wall assembly  12 . The outer face  60 , or at least portions thereof, is adopted to support various flashing members installed on top of the cant member  40 . The cant member  40  includes a wall or upper portion  62  extending longitudinally, a lower portion  64  likewise extending longitudinally and spaced from the upper portion  62  and a cant portion  66  also extending longitudinally and positioned intermediate and joining the upper and lower portions  62 ,  64  on the member  40 . As the names imply, the wall or upper portion  62  is intended to be oriented generally vertically and juxtaposed to the interior wall  28  of the wall assembly  12  when the cant member  40  is installed and, likewise, the lower portion  64  is adapted to be oriented generally horizontally and juxtaposed against the generally horizontal ledge  22  of the wall assembly  12  or a vertical portion of the wall assembly  12 . The cant portion  66  between the wall and lower portions  62 ,  64  of the flashing member  40  is intended to extend between the wall and vertical or horizontal portions and to be oriented generally at a 45° or other angle oblique to the interior wall  28 , vertical portion  46  or ledge  22 ,  22   a  of the wall assembly  12  in this embodiment. 
     The cant member  40  includes the layer of adhesive  50  on the inner face  54  of the upper portion  62  to secure the cant member  40  to the interior wall  28 . The layer of adhesive  50  is covered by a layer of release paper  56  adapted to be removed from the adhesive layer  50  ( FIG. 2A ). Additionally, a second layer of adhesive  52  is positioned on the inner face  54  of the cant member  40  in the lower portion  64  which is likewise covered by a layer of release paper  56 . 
     The outer face  60  of the upper portion  62  of the cant member  40  includes a series of generally parallel scores or slits  68  extending longitudinally. The slits  68 , eight of them in one embodiment, permit a portion of the cant member  40  to be shaped to conform to the configuration of the interior wall  28  for proper positioning and adhesive application to the interior wall. A pair of scores or slits  70  are formed on the inner face  54  of the cant member  40 , one at the juncture between the upper portion  62  and the cant portion  66  and another at the juncture between the lower portion  64  and the cant portion  66  to allow for easy manipulation of the cant member  40  for configuration into the orientation shown in  FIG. 2A  from the generally planar orientation shown in  FIG. 2 . A slit or score may also be provided on the outer face  60  at the juncture between the cant and lower portion  64 ,  66  to enable the cant member  40  to bend into the configuration shown in  FIG. 3 . 
     When properly positioned in the wall assembly  12 , the inner face  54  of the upper portion  62  should be generally flat against the vertical, interior wall  28  and the inner face  54  of the lower portion  64  should be generally horizontal and flat against the ledge  22  of the wall assembly  12  with the cant portion  66  connecting the upper and lower portions at about a 45° angle. With the cant member  40  generally oriented in this configuration as shown in  FIG. 2A , the release paper  56  from the layer of adhesive  50  on the inner face  54  of the upper portion  62  can be removed while maintaining proper orientation of the flashing member  40  in the wall assembly  12 . Once the position of the cant member  40  is confirmed and alignment with respect to the lower portion  64  is maintained, then the release paper  58  can be removed from the lower portion  64  and the cant member  40  pressed into position in the wall assembly  12  and being adhered thereto by the layers of adhesive  50 ,  52 . Alternatively, flathead or other mechanical fasteners can be used to secure the cant member  40  in place 
     The forward edge of the lower portion  64  relative to the drip edge when initially installed in the wall assembly  12  should be located and any excess of the lower portion  64  extending beyond the drip edge  48  should be trimmed. In an alternative wall assembly installation shown in  FIG. 3 , the orientation of the lower portion  64  may be generally vertical or angled obliquely relative to the horizontal plane so as to conform to the downwardly turned lip of the drip edge  48 . 
     The orientation and installation of the cant member  40  as shown in  FIG. 4  may require miter cut joints of the adjacent portions of the flashing member  40  at the interior and exterior corners of any such installations in the wall assembly  12 . Otherwise, the installation of the cant member  40  is similar to that described herein above with respect to  FIG. 3 . Exemplary, but non-limiting, types of installations according to  FIG. 3  include veneer along shelf angles and veneer heads at non-flanged windows, doors and fixtures. Typically, the horizontal spacing between the vertical components  36  and  46  in  FIG. 3  is at least ⅛″. Alternatively, the cant member  40  can be installed once rotated from top to bottom to accommodate different applications and installation configurations while satisfying construction, inventory and purchasing requirements. 
     The cant member  40  of this invention is intended to be at least partially covered by a flashing member  72  and support that flashing member  72 , particularly along the cant portion  66  of the cant member  40  underlying the flashing member  72  ( FIG. 4 ). An unsupported flashing member  72  will fail over time and the proper use of the cant member  40  inhibits such a failure. Exemplary, but non-limiting, types of installations in which the cant member of this invention as shown in  FIG. 4  include veneer ledges, veneer risers, veneer at a wall to slab interface, veneer sills at flanged windows, doors and fixtures, veneers above lintels, veneers at wall to roof intersections, parapet wall at roof intersection, veneer at deck framing and applied exterior finish sills or thresholds at flanged windows, doors and fixtures. 
     As such, with this invention in anyone of various embodiments, the cant member is adapted for use specifically in above grade through wall flashing installations. It is a supporting component for adhered or non-adhered flashing membranes that are the waterproofing part of a flashing assembly. The cant member itself is not a flashing device, but a device that supports a flashing member at gaps between walls and fixtures, i.e. angle irons, and at transitions from vertical to horizontal or spaced vertical planes typically located at a bottom of a wall section. The cant member also maintains a directional flow of water toward the exterior face of a wall, over the more important flashing parts, namely the membrane and exposed hard surface drip edge. Without the aid of a supporting cant member of this type, the flow of water could be trapped in undulations along the supporting horizontal leg of the flashing or where there would be a negative pitch back toward the interior side of the flashing assembly caused by construction irregularities. This invention avoids the problems associated with known cant devices typically formed with 2-part materials that are mixed, applied and shaped, and then harden to support a flashing membrane. While this method is used extensively below grade, the trades involved with installing flashing above grade often dispense with the prior mixed version of the cant in favor of none at all because of timing sensitivity. This invention is an above grade answer to the inconvenience of mixing, applying, shaping and waiting for a material to harden. 
     While the cant member has been shown herein in various environment and installations, it is not limited to any particular environment such as windows and doors, but is applicable for use at the transition of vertical to horizontal wall assembly components in general and bridging gaps between spaced, vertical wall components. Furthermore, the method of attachment for the cant member is not limited to any particular method, but any method effective to hold the cant member in place long enough to be covered by a flashing member is envisioned. 
     From the above disclosure of the general principles of the present 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.