Patent Publication Number: US-2009229209-A1

Title: Single Ply Roofing System

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of the filing of U.S. application Ser. No. 11/925,601, entitled “Single Ply Roofing System”, by Thomas Crego, et al., filed on Oct. 26, 2007, which application claims priority to and the benefit of the filing of U.S. Provisional Patent Application Ser. No. 60/891,367, entitled “Single Ply Metal Roofing System”, by Thomas Crego, et al., filed on Feb. 23, 2007, and the specifications and claims, if any, thereof are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention (Technical Field) 
     The present invention relates to a method and apparatus for a metal roofing system. Particularly, the present invention relates to an improved single ply metal roofing system which permits the use of thicker sheeting than the prior art while solving thermal expansion and contraction issues which plague the prior art systems. 
     2. Description of Related Art 
     Known metal roofing systems permit only a maximum thickness of 30 gauge metal-sheeting to be applied to a roof. Such known systems rely on “hat” channel  2  disposed on a roofing substrate, (see prior art  FIG. 1 ). The sheeting is screwed into the hat channel which fixedly holds the sheeting in place and prevents if from moving. Securing the sheeting to an inflexible member, such as a hat channel, prevents the sheet metal from being able to expand and contract with thermal cycling. Thermal expansion and contraction forces on the sheeting increase as the thickness of the metal increases. Accordingly, known systems cannot apply thicker and more substantial sheeting because thermal expansion and contraction occurs which results in excessive expansion and contraction of the metal. The excessive expansion and contraction of such metal-sheeting results in excessive forces being applied to the fasteners that are driven through it. These excessive forces cause the fasteners to either become loose or cause the sheeting to pull away from the fasteners; either of these scenarios results in a loose fit between the fastener and the sheeting, thus permitting water to pass between the fastener and the sheeting, thereby breaching the surface of the roof. 
     Because the known metal roofing systems are limited to a maximum thickness of only about 30 gauge, those systems are easily punctured. For example, puncturing may occur by a worker simply dropping a screwdriver during installation or dropping a tool while performing any other work on a roof, i.e. repairing a heating, ventilation, and air conditioning unit. Accordingly, a quick patch is not at all uncommon and such patches themselves often result in point of water entry several years later. 
     Yet another problem with known single ply roofing systems is that the roofing sheets are held to the top of the structure by screwing the edges of the roofing sheets onto hat channels that are disposed on the top of the structure. The hat channels themselves are modified, non-flexible, channel-iron members which rigidly and fixedly hold the roofing sheets in place. When the roofing sheets expand and contract, because their edges are held firmly held in place, the roofing sheets must thus bow up in their central region. This continuous rising and falling of the central portion of each of the sheets in response to thermal expansion and contraction, coupled with the row of fasteners around the periphery thereof, results in metal fatiguing of the roofing sheets along the inside edge of the metal fasteners. Over time, the constant cycling of thermal contractions and expansions thus causes the breaks in the roofing sheets which thus enables water to breach the roofing surface. Because even thicker roofing sheeting experiences even greater expansion and contraction cycles, attempts to secure thicker sheeting to the known hat channels results in even more extreme rising and falling of the central portion of the sheets in response to the thermal expansions and contractions. This extreme rising and falling of the sheets results in metal fatiguing of the roofing sheeting in a much more rapid manner than what is typical. 
     Although insulating sheeting can and often is applied between the hat channels immediately below the roofing sheeting, the space beneath the hat channels typically remains un-insulated. Because the air within the un-insulated metal hat channels is exposed to warm and cold temperature cycles, condensation often forms along the inside of the hat channels. This condensation often results in non-protected metal surfaces rusting (i.e. the fasteners that are driven through the hat channels and which hold the sheeting thereto). The rusting of the very components that hold the metal roofing structures together is obviously a very undesirable quality in the known metal roofing structures. 
     Known metal roofing systems also provide undesirable flashing. This is because the flashing that is used to trim outer portions of known roof structures do not have an interlocking structure that adequately prevents water from blowing, splashing, or otherwise traveling therebetween, thus resulting in water breaching the roofing surface. Known metal roofing systems typically rely on a two-piece flashing arrangement wherein the upper portion of the flashing extends slightly beyond the lower portion. This simple overlap joint does not provide an effective seal in all instances. 
     There is thus a present need for a single ply metal roofing system which permits a thicker sheeting to be applied and which avoids metal fatiguing of the roofing sheeting and which further avoids the use of metal structures that permit condensation to form therein. There is also a present need for a metal roofing system that provides flashing which effectively prevents splashing and wind-driven rain from breaching the roof surface. There is yet another present need for a metal roofing system that more adequately resists puncturing of sheet metal while it is being installed and while other roof work is subsequently performed. 
     BRIEF SUMMARY OF THE INVENTION 
     An embodiment of the present invention relates to a roofing system for an existing roofing substrate having at least one flexible support, the flexible support attached to the roofing substrate, and at least one layer of sheeting, the sheeting attached to the flexible support such that the flexible support flexes when the sheeting thermally expands and/or contracts. The insulating materials can be disposed above the roofing substrate and below the sheeting. The insulating materials can have a thickness of about 1 inch or more. In one embodiment, the sheeting is preferably a metal material and most preferably a steel material. 
     In one embodiment, at least a portion of the sheeting can comprise a thickness of from about 31 gauge to about 22 gauge, and most preferably a thickness of about 26 gauge. A waterproofing material can be disposed between overlapping portions of the sheeting. 
     In one embodiment, the roofing system of the present invention comprises at least one fastener which most preferably comprises a stainless steel material. 
     In one embodiment, the roofing system of the present invention preferably comprises a lower flashing component fastened to an upper surface of the sheeting and an upper flashing component fastened to an at least substantially vertical surface. The upper and lower flashing components most preferably interlock to form a slidable connectable therebetween. 
     Embodiments of the present invention also optionally comprise at least one expansion joint. 
     An embodiment of the present invention relates to a method of installing a roofing system on a roofing substrate including attaching at least one flexible support to an upper portion of the roofing substrate and fastening a portion of a first sheeting at least partially onto an upper portion of the flexible support member. The method can also include disposing a portion of a second sheeting at least partially onto an upper surface of the first sheeting and/or disposing one or more insulating materials above the roofing substrate and abutting at least one of the insulating materials to at least one of the flexible support structures. In one embodiment of the present invention, the method can include fastening the lower flashing component to an end portion of the at least one layer of sheeting and fastening the upper flashing component to a wall, which can also further include slidably connecting the lower flashing component to the upper flashing component. Optionally, the method can also include installing at least one expansion joint. 
     The method can also include disposing a waterproofing material between at least some of the overlapping portions of the first and second sheeting. In the method, one or more coatings of material can be applied onto at least a portion of the sheeting. 
     Objects, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The accompanying drawings, which are incorporated into and form a part of the specification, illustrate one or more embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating one or more preferred embodiments of the invention and are not to be construed as limiting the invention. In the drawings: 
         FIG. 1  is a cut-away view drawing of a prior art metal roofing system; 
         FIG. 2  is a cut-away view drawing illustrating an embodiment of the single ply metal roofing system of the present invention; 
         FIG. 3  is an exploded view schematic drawing illustrating an embodiment of the present invention; 
         FIG. 4  is a perspective view of a Z-shaped flexible support according to an embodiment of the present invention; 
         FIG. 5  is a cut-away side view illustrating a blind seam in accordance with an embodiment of the present invention; 
         FIG. 6A  is a cut-away side view illustrating an embodiment of the flashing of the present invention; 
         FIG. 6B  is a perspective view drawing illustrating an embodiment of the flashing of the present invention; 
         FIGS. 6C  and D respectively illustrate top, bottom, views of a most preferred embodiment of the flashing of the present invention; 
         FIG. 6E  illustrates a side view of a most preferred embodiment of the flashing of the present invention, in this most preferred embodiment, both of the left and the right side views of the flashing are the same; 
         FIGS. 6F  and G respectively illustrate front and back views of a most preferred embodiment of the flashing of the present invention; 
         FIG. 7  is a close-up side view illustrating a preferred embodiment of the interconnection between the upper and lower flashing halves; 
         FIG. 8  is a perspective view drawing illustrating an embodiment of the drip edge of the present invention; 
         FIG. 9  is a perspective view drawing illustrating an embodiment of an expansion joint of the present invention; 
         FIG. 10  is a perspective view drawing illustrating an alternative embodiment of an expansion joint of the present invention; 
         FIG. 11  is a drawing illustrating some of the possible design shapes for flexible support members of the present invention; 
         FIG. 12  is a drawing illustrating an embodiment of the roofing system of the present invention wherein a vent is provided; 
         FIG. 13  is a cut-away drawing illustrating an embodiment of the vent of the present invention; 
         FIG. 14A  is a perspective view of alternative embodiments of seam caps according to an aspect of the present invention; and 
         FIG. 14B  is a perspective view illustrating a roofing system with a seam cap in accordance with an aspect of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments of the present invention are directed to a metal roofing system. Particularly, embodiments of the present invention are directed to a metal roofing system which simultaneously provides thicker roofing sheeting and allows for thermal expansion and contraction without the adverse effects which are common to conventional systems. 
     Although the present invention is particularly directed toward metal roofing systems, the teachings of the present invention are not limited strictly to metals and can provide desirable results when used with other materials including but not limited to coated metals, metal alloys, composites, plastics, rubbers, fiberglass, other solid materials that are water resistant, combinations thereof, and the like. Accordingly, the terms “sheeting” and “flexible support” as used throughout the specifications and claims is intended to include all of these materials. 
     As used throughout the specification, the term “wall” is not limited strictly to the conventionally-defined wall, but rather, includes any surface or structure which a user wishes to bridge to the sheeting of the present invention with one or more flashings. 
     As used throughout the specification, the term “flexible support” includes all structures that flexibly bend and give in a manner which accommodates expansion and contraction of sheeting fixed thereto and can include any of the shapes illustrated on  FIG. 11  and the like. As illustrated in  FIG. 11 , the flexible supports of the present invention preferably comprise an upper surface which extends beyond and thus overhangs one or more supporting upright portions thereof. Accordingly, the term “flexible support” does not include a hat channel disposed with its opening facing a roofing substrate as is used in the prior art. 
     As illustrated in  FIGS. 2 and 3 , an embodiment of the present invention is directed to roofing system  10 , which is most preferably a single ply roofing system. Roofing substrate  12  preferably has flexible support  14 , which is also preferably metal, attached thereto. While roofing substrate  12  is most preferably a solid and flat surface, roofing substrate  12  can be formed from spaced apart beams. Attachment of flexible support  14  can be made to roofing substrate by fasteners and/or fastening methods known to those skilled in the art, including but not limited to, welding, riveting, screwing, nailing, gluing, combinations thereof, and the like. Flexible support  14  preferably has a plurality of fastener holes disposed along a length thereof for attachment to roofing substrate  12 .  FIG. 4  illustrates a most preferred embodiment of flexible support  14  which preferably has two fastener holes  15  about 1″ from a first edge of flexible support  14  and another set of two fastener holes  15  about 6″ from the same edge of flexible support  14 , thereafter, flexible support  14  is most preferably fastened to roofing substrate  12 , through holes  15 , about every 6″ along its length. Providing two or more holes at predetermined distances along a primary length of flexible support  14  enables an installer to attach flexible support  14  to substrate  12  more securely in that installers are less likely to install a single row of fasteners, which could otherwise enable flexible support  14  to rock back and forth, thus eventually loosening a single row of fasteners. Further, providing holes at predetermined distances helps to ensure that an installer of the roofing system will insert fasteners at the location of the holes and thereby helps to ensure that the fasteners are installed through the flexible supports at specified locations, thus improving installation consistency and quality. While not essential, one or more insulating materials  16  are preferably disposed above substrate  12  and abut flexible support  14 . In a most preferred embodiment, insulating materials  16  preferably comprise an expanded or extruded polystyrene foam material. In yet another preferred embodiment, insulating materials  16  are preferably at least 1 inch thick or have a thickness of about the height of flexible support  14 . Insulating materials  16  can also preferably include a lap joint or some other type of joint so each insulating piece locks together or partially overlaps one another, which avoids butting two pieces of insulation together which can result in a small gap at the joint that has no insulation. 
     Sheeting  18  is preferably disposed at least partially on top of flexible support  14  and is fastened thereto via one or more fasteners  20 . As previously discussed, sheeting  18  can be a constructed from virtually any rigid, semi-flexible, or flexible material depending upon the particular environment, application, and results to be achieved for a particular location as will be apparent to those skilled in the art. In a most preferred embodiment, however, sheeting  18  preferably comprises a metal and even more preferably a steel material. Sheeting  18  can comprise virtually any gauge of thickness, depending upon the application and environment as will become apparent to those skilled in the art upon studying this application. Sheeting  18 , however, preferably comprises a thickness of from about 11 gauge to about 36 gauge, and more preferably from about 22 gauge to about 32 gauge. In a most preferred embodiment, sheeting  18  comprises a thickness of about 26 gauge. Although sheeting  18  is illustrated in  FIG. 2  as having a patterned surface, sheeting  18  can comprise a flat smooth surface, a rough and/or textured surface, a patterned surface, or another surface, in a most preferred embodiment, sheeting  18  preferably comprises ribs or bends also known as “mesas”, disposed along the width of sheet  18 , which are about 1/32 of an inch to about ⅜ of an inch in height and which are most preferably about 3/32 of an inch in height. 
     In a most preferred embodiment, waterproofing material  22 , such as for example butyl-tape, rubber stripping, roofing tar, and the like, which preferably has a width of about one inch to about 6 inches, and more preferably has a width of from about 1 inch to about 4 inches, and most preferably a width of about 2 inches, is preferably sandwiched between successive overlapping edge portions of sheeting  18 , as best illustrated in the exploded view of  FIG. 3 . Each consecutive edge portion of sheeting  18  preferably made to overlap directly above flexible support  14 . Waterproofing material  22  is also preferably disposed between the overlapping end portions of sheeting  18  directly above flexible support  14 . Because each of the overlapping edge portions of sheeting  18  and waterproofing material  22  preferably reside directly above flexible support  14 , one or more fasteners  20  can thus be used to secure all of them together. 
     Although those skilled in the art will appreciate that numerous types of fasteners and fastening methods can be used for fastener  20 , in a preferred embodiment, fastener  20  preferably comprises a screw-type fastener, and more preferably a rust-proof screw-type fastener, such as a galvanized screw, a powder-coated screw, a painted screw, and/or a screw made from a rust resistant material. In a most preferred embodiment, fastener  20  comprises a stainless steel screw-type fastener. 
     Because the upper portion of flexible support  14  is not in a rigid and staunch position with respect to the bottom portion, as in the hat channels of the prior art, but can instead easily flex, sheeting  18  attached thereto is thus not rigidly and fixedly secured to roofing substrate  12 . Because of the flexible nature of the flexible supports of the present invention, when sheeting  18  expands and contracts due to thermal cycling, and/or high winds, excessive forces are not applied to or around fasteners  20 . Because excessive forces are not applied to fasteners  20  from sheeting  18 , fasteners  20  do not substantially loosen and thus a water-resistant seal is maintained around them. In addition, because excessive forces are not applied around metal fasteners  20  by sheeting  18 , the holes within sheeting  18 , through which fasteners  20  pass, do not become enlarged, further enabling the present invention to maintain a water resistant seal. In addition, because the sheeting of the present invention is not rigidly held in place as in the prior art, during expansions and contractions excessive fatiguing of sheeting  18  does not occur. 
     In one embodiment, flexible support comprises a multi-axial flexible support which has an upper portion that can flex in more than one direction with respect to its lower portion and which upper portion can most preferably can flex not only from side to side, but also up and down with respect to its lower portion. In one embodiment the flexible support and multi-axial flexible support comprises an upper portion which has an end portion which is disposed a distance away from and thus does not reside directly above a substantially perpendicular supporting member of the flexible support and/or the multi-axial flexible support. 
       FIG. 5  illustrates a blind seam constructed in accordance with an embodiment of the present invention. As those skilled in the art are aware, a blind seam is typically provided in metal roofing when a change in pitch occurs. Accordingly, blind seams often occur along an inner area of a portion of sheeting and not necessarily along an edge portion thereof. As illustrated therein, insulating materials  16  are preferably cut or otherwise provided such that they terminate at or near the desired location of the blind seam. Flexible support  14  is preferably secured to substrate  12  at the desired location of the blind seam. Insulating materials  16  are thus preferably caused to abut flexible support  14 . Waterproofing material  22  is preferably disposed on a top portion of flexible support  14 . Sheeting  18  is then preferably positioned above the location of the blind seam and one or more fasteners  20  are used to attach sheeting  18  to an upper portion of flexible support  14 . 
     Referring now to  FIGS. 6A-6G , a preferred embodiment of metal flashing  24  is illustrated. As illustrated therein, lower flashing component  26  is preferably fastened to an end portion of sheeting  18 . While numerous manners of attachment will become apparent to those skilled in the art upon studying this application, a preferred embodiment of the present invention provides flexible support  14 , fastened to substrate  12  via one or more fasteners  20 , abutted next to insulating material  16  wherein sheeting  18  is disposed on top of an upper surface of flexible support  14  and wherein waterproofing material  22  is preferably disposed on an upper surface of sheeting  18 , substantially above flexible support  14  and wherein a lower end portion of lower flashing component  26  is disposed thereabove. One or more fasteners  20  are most preferably provided which fasten lower flashing component  26  through waterproofing material  22  and sheeting  18  to flexible support  14 . Upper flashing component  28  is preferably fastened to wall  30  of a structure which lies near an end portion of sheeting  18 . Most preferably, waterproofing material  22  is disposed between wall  30  and an upper end portion of upper flashing component  28 . One or more fasteners  20  are preferably used to fasten upper flashing component  28  to waterproofing material  22  to wall  30 . In a most preferred embodiment, lower flashing component  26  is preferably slidably connectable to upper flashing component  28 .  FIG. 7  is a close-up drawing illustrating a preferred interconnection between upper component  28  and lower component  26 . Because of the wraparound connection configuration, not only are the upper and lower portions of metal flashing  24  able to move freely due to thermal expansions and contractions associated with it, the roof, and the wall, but it is also virtually impossible for water to pass therethrough. Accordingly, flashing  24  of the present invention provides a water-resistant seal even when faced with splashes and wind-driven rains. 
     In one embodiment, a primer is applied to one or more surfaces of the metal components of the present invention before a finishing coating is applied. Although any finishing coating, which can be applied to the one or more metal surfaces and which provides rust resistance, will provide desirable results, a most preferred finishing coating is Valspar&#39;s WeatherX™ coating. 
       FIG. 8  is a drawing illustrating a drip edge according to an embodiment of the present invention. As illustrated therein, near an end portion of roof substrate  12 , flexible support  14  is preferably attached thereto with one or more fasteners  20 . As illustrated in  FIG. 8A , a drip edge of the present invention preferably comprises a j-shaped piece of material for flexible support  14 , of course, numerous other shaped pieces of material can be utilized and will produce desirable results as will be recognized by those skilled in the art upon studying this application. Insulating material  16  is preferably disposed atop a lower portion of flexible support  14 . Drip strip  32  preferably comprises one or more bends which enable an upper portion of drip strip  34  to be sandwiched between an upper portion of flexible support  14  and weatherproofing material  22 . As further illustrated in  FIG. 8 , sheeting  18  is preferably secured to an upper portion of weatherproofing material  22  via one or more fasteners  20 . Fasteners  20  not only secure sheeting  18  and weatherproofing material  22 , but also secure an upper portion of flexible support material to an upper portion of drip strip  32 . 
       FIGS. 9 and 10  illustrate embodiments of expansion joint  34  of the roofing system of the present invention. Although expansion joints  34  can produce desirable results at virtually any spacing, expansion joints  34  are preferably provided about every 20 to about every 350 feet along roofing substrate  12 . Expansion joints  34  are more preferably provided about every 50 feet to about every 200 feet along roofing substrate  12 . In a most preferred embodiment, expansion joints  34  are preferably provided about every 100 to about every 150 feet along roofing substrate  12 . While  FIGS. 9 and 10  illustrate expansion joints comprising particular configurations, those skilled in the art will appreciate that expansion joints can be provided in various shapes, sizes, and configurations and desirable results will still be achieved. As illustrated in the  FIGS. 9 and 10 , expansion joint  34  is preferably formed by disposing expansion strip  36  between two portions of sheeting  18 . Weatherproofing strip  22  is preferably sandwiched between expansion strip  36  and sheeting  18  via one or more fasteners  20 . An upper portion of one or more flexible support members  14  is preferably secured to sheeting  18  and expansion strip  36  via one or more fasteners  20 . A lower portion of flexible support member  14  is preferably secured to roofing substrate  12  via one or more fasteners  20 . As illustrated in the figures, insulating material  16  is preferably disposed on each side of and/or between the one or more flexible support members  14  to which expansion strip  36  is connected. As previously discussed, flexible support members  14  can comprise numerous shapes, as illustrated in  FIG. 9 , flexible support members  14  comprise a z-shape, while  FIG. 10  illustrates flexible support member as comprising an upside-down hat channel. 
       FIG. 11  illustrates just a handful of the numerous shapes which flexible support members  14  can comprise. As previously mentioned, the shape of the flexible supports of the present are not limited to just those illustrated, but can include any shape which, unlike the hat channel of the prior art (wherein sheeting is attached to a central upper portion of the hat and the legs of the hat are attached to a roofing substrate), can accommodate thermal expansion and contraction of the sheeting of the present invention. 
       FIG. 12  illustrates an embodiment of the present invention wherein a portion of roofing system  10  comprises vent  40 . As best illustrated in the cut-away view drawing of  FIG. 13 , vent  40  preferably comprises hollow section  42 , flap  44 , and lip  46 , which together form a one-way check valve that allows air to escape through hollow section  42  from the area between roofing substrate  12  and sheeting  18 , but which inhibits the flow of air through hollow section  42  into the area between substrate  12  and sheeting  18 . Although a particular design of a one-way vent is illustrated, any design of a one-way vent will provide desirable results so long as the one-way vent permits air to escape from beneath sheeting  18  and which most preferably inhibits the flow of air beneath sheeting  18 . Accordingly, vent  40  helps keep sheeting  18  in a flattened position and prevents the buildup of air between roofing substrate  12  and sheeting  18  which would tend to cause sheeting  18  to bow upwards and lift away from substrate  12 . In order to prevent rain water and other contaminants from passing through hollow section  42  of vent  40 , cover  48  is preferably provided above hollow section  42 . Although various sizes and spacing of vent  40  can be provided while producing desirable results, in a preferred embodiment, hollow section  42  preferably comprises a cross-sectional area of from about 4 square inches to about 600 square inches and most preferably from about 8 square inches to about 64 square inches and vent  40  is most preferably provided at a spacing of about one for every 500 square feet of sheeting used. 
       FIGS. 14A  and B illustrate seam cap  50  prior to and after installation onto an exposed end portion of seam  52  of sheeting  18  which end portion has been caused to be exposed due to an overlapping joint or another termination of sheeting  18 . An exposed end of factory seam  52  can provide an entry point for water within the roofing system of the present invention, which can be wicked along seam  52  of sheeting  18 . It is thus desirable to reduce or prevent the exposure of an end of factory seam  52 .  FIG. 14A  illustrates an embodiment of seam cap  50  and its alternative embodiment of seam cap  50 ′. As illustrated therein, seam cap  50  is most preferably provided in the shape of an angled piece of material, preferably a thin metal material, having a lower portion and an upper portion. Alternatively, seam cap  50 ′ is provided which has a channel shape. In one embodiment, the lower portion of seam cap  50  is preferably slid under sheeting  18  at the termination portion of factory seam  52 . A water-proofing calking or another water-proofing material can be disposed over and/or around the exposed end of seam  52  and the remaining upward protruding portion of seam cap  50  is bent over sheeting  18  so as to cover the exposed end of factory seam  52  after which time one or more fasteners can be provided through an upper portion of cap  50 , sheeting  18 , and lower portion of seam cap  50  at or near seam  52 , thus sandwiching the exposed end of seam  52  within the water-proofing calking or other material (see  FIG. 14B ). In the embodiment of seam cap  50 ′ a water-proofing calking or other waterproofing material is first either disposed on and around a terminal portion of factory seam  52  or is optionally disposed with the channel seam cap  50 ′. Seam cap  50 ′ is then preferably slid around sheeting  18  at the terminal portion of seam  52 , thus trapping the exposed end portion of factory seam  52  within water-proofing calking or another waterproofing material and seam cap  50 ′ (see  FIG. 14B ). The end result achieved when using either seam cap  50  or seam cap  50 ′ is basically the same. 
     Although the invention has been described in detail with particular reference to these preferred embodiments, other embodiments can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art and it is intended to cover all such modifications and equivalents. The entire disclosures of all references, applications, patents, and publications cited above and/or in the attachments, and of the corresponding application(s), are hereby incorporated by reference.