Patent Publication Number: US-11646692-B2

Title: Waterproofing mounting system for attaching solar modules to a roof

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. nonprovisional application with Ser. No. 17/096,839 filed Nov. 12, 2020, now granted as U.S. Pat. No. 11,139,774, and which is a continuation of United States nonprovisional application with Ser. No. 16/539,134 filed Aug. 13, 2019, now granted as U.S. Pat. No. 10,868,491, which is a continuation of United States nonprovisional application with Ser. No. 16/380,918 filed Apr. 10, 2019, now granted as U.S. Pat. No. 10,511,252, which is a continuation of U.S. nonprovisional patent application Ser. No. 16/160,504 filed Oct. 15, 2018, now granted as U.S. Pat. No. 10,211,775, which is a continuation of United States nonprovisional patent application Ser. No. 15/803,656 filed Nov. 3, 2017, now granted as U.S. Pat. No. 10,103,683, which is a continuation of United States nonprovisional application with Ser. No. 15/225,704 filed on Aug. 1, 2016 and now granted as U.S. Pat. No. 9,755,572, which is a continuation of United States nonprovisional application with Ser. No. 15/045,434 filed on Feb. 17, 2016 and now granted as U.S. Pat. No. 9,712,106, which is a continuation of United States nonprovisional application with Ser. No. 14/605,368 filed on Jan. 26, 2015, now granted as U.S. Pat. No. 9,813,012, which is a continuation of United States nonprovisional application with Ser. No. 14/166,633 filed on Jan. 28, 2014, now granted as U.S. Pat. No. 8,938,932 and which claims the benefit of provisional patent application with Ser. No. 61/916,046 filed on Dec. 13, 2013. 
    
    
     BACKGROUND OF THE DISCLOSURE 
     Technical Field of the Disclosure 
     The present embodiment relates in general to mounting systems for photovoltaic (PV) modules on roof structures. More specifically, the present disclosure relates to a rail-less photovoltaic (PV) module mounting system for providing a cost-effective means to install a plurality of photovoltaic (PV) modules on a roof structure. 
     Description of the Related Art 
     With the increased use of photovoltaic (PV) roofing systems for generating electricity, a demand for mounting hardware, which attaches frames for the purpose of installing the PV modules to the roof structure or any other support structure, has been developed. In recent years, various kinds of mounting structures have been used which allow the installation of PV modules to the roof structures. Mounting structures come in a variety of sizes and patterns to meet installation purposes. However, most of the mounting structures require increased labor time and cost for installation of the PV modules on the roof structures. 
     Conventional mounting structures for supporting PV modules in frames have considerable drawbacks. For example, many mounting structures utilize rails to mount the PV modules to the roof structure to form a PV array. The use of these rails requires additional materials to support the PV modules. Because of use of the additional material, these traditional mounting structures can result in excess shipping costs. They can also limit the PV array layout possibilities and dramatically increase the time for designing, engineering and installing the mounting structures. Existing devices are expensive, difficult to use and can require additional manpower to install. For example, a typical 5 kW PV mounting system designed to mount 20 PV panels (15.37% efficient) mounted on a traditional rail mounting system requires approximately 302 parts at a total cost of $0.69/W retail for the mounting structure only and weighs over 300 Lbs. Typical installation times for a simple 4×5 (4 rows and 5 columns) PV module rail based mounting system are approximately 49 man-hours. 
     Traditional rail mounting systems require 5 penetrations per mount, 4 mounts per PV module, additional grounding lugs, and requires specifically engineered PV modules. In addition, existing rail mounting systems may have substandard waterproofing for roof penetrations, along with complex grounding, wire management, and increased labor time on the roof structure due to design flaws. Hard and soft balance of system (BOS) may include bypass diodes, blocking diodes, solar controller, wiring system, battery and/or inverter etc. The hard and soft balance of system (BOS) costs for PV rail mounting system are high due to high material costs as well as long system engineering and installation times. Also, the traditional rail mounting systems require long strings that are difficult to break up, causing difficulty in working around roof obstructions (e.g. vents, skylights). 
     One of the existing mounting systems describes an integrated module frame and racking system for a solar panel. The system comprises a plurality of solar modules and a plurality of splices for coupling the plurality of solar modules together. The plurality of splices provide a way to make the connected modules mechanically rigid both during transport to the roof and after mounting for the lifetime of the system; provide wiring connections between modules; provide an electrical grounding path for the modules; provide a way to add modules to the panel; and provide a way to remove or change a defective module. Connector sockets are provided on the sides of the PV modules to simplify the electrical assembly when the PV modules are connected together with splices. However, the frame of the PV module is installed with a groove to attach the mounting bracket and a hole to insert the splice to connect the PV modules, which results in a labor-intensive operation. In addition, it requires one mounting bracket per PV module and multiple holes in the roof structure are required for installation, increasing the risk of leaks. 
     Another existing mounting system discloses a photovoltaic (PV) module framing and coupling system which enables the attachment of PV modules to a roof or other mounting surface without requiring the use of separate structural support members. The system provides a parallel coupling for securely interlocking the outside surfaces of parallel frame members together in a side-to-side arrangement to form an array with improved structural load distribution. The coupling member may attach to a slot in the frame at substantially any position along the length of the frame thereby enabling the interconnection of adjacent PV modules along both an x and y-axis. The system may further provide a rotating portion and locking portion for coupling to the frame attachment, mounting brackets for direct connection to a mounting surface, grounding teeth for the automatic creation of a reliable two axis grounding matrix, and a rapid twist-lock engagement means for reliably interlocking and aligning PV modules in the array. However, this embodiment includes a side-to-side arrangement to form an array and an additional groove/slot is formed on the frame to engage coupling member, which enables the interconnection of frames of adjacent PV modules. In addition, the parallel couplings are extended beyond corner regions of PV modules. 
     Various other mounting systems currently available are impossible to retrofit to existing roofs without cutting the shingles. The removal of a single PV panel from the PV array installed using some of these aforementioned mounting structures is difficult and can result in re-work thereby increasing labor and material costs. Some other systems do not allow for the capability to independently remove a single PV panel without deconstructing an entire row of PV panels, which significantly increases maintenance costs. 
     Therefore, there is a need for a rail-less roof mounting system that would provide a cost effective and improved means for PV module installations. Such a rail-less roof mounting system would provide an efficient means of installation that does not require any additional material or structure to support the rail-less roof mounting system. Such a rail-less roof mounting system would provide a corner-to-corner coupling arrangement enabling the bridging of a PV module corner directly with adjacent PV module corner. Such a needed device would provide reduced shipping and hardware costs, labor and installation time and cost; reduce the dead load on the roof structure along with design engineering costs; and hard and soft balance of system (BOS) cost. This rail-less roof mounting system would provide a single grounding lug and a single point of penetration with an elevated seal portion for waterproofing the roof structure. Such a rail-less roof mounting system would typically be designed for implementation on composition shingle roofs, tile roofs, metal roofs, low slope roofs, or any roof that would benefit from being waterproof. This mounting system would also provide simple grounding, wire management, and structural quality. This system would be simple, inexpensive, and lightweight. This system would provide an improved engineering design to accommodate high snow and wind loads. Further, this rail-less roof mounting system would allow an installer to easily work around roof obstructions like vents, skylights, and other roof protrusions. This system would also minimize the number of parts and tools needed to assemble and install the PV module. This rail-less roof mounting system would provide the ability to increase vertical leveling adjustability; to independently remove a single PV module without deconstructing an entire row of the PV array; and allow for easy mounting height adjustment after PV modules are installed. Finally, this rail-less roof mounting system would require less manpower to install and rework. 
     SUMMARY OF THE DISCLOSURE 
     To minimize the limitations found in the prior art, and to minimize other limitations that will be apparent upon the reading of the specifications, preferred embodiment of the present invention provides a rail-less roof mounting system for installing a plurality of photovoltaic (PV) modules on a roof structure. The rail-less roof mounting system comprises a base mount assembly attached to the roof structure. The base mount assembly includes a base member having a top surface and a bottom surface, a block slider having an elevated seal portion and a vertical engaging portion, and a top slider having a top portion and a bottom portion, and a clamp assembly having a clamp member and a plate member. 
     The top surface of the base member is attached with a waterproof means and the bottom surface of the base member is engaged with the roof structure. The elevated seal portion, having a borehole formed therethrough to receive the waterproof means, engages with the base member and the roof structure, utilizing at least one tightening means that is inserted through the borehole. The vertical engaging portion has a vertical groove along a surface thereof. The top slider having a track with a horizontal groove at the top portion and a sliding seal member with a sliding groove and an opening at the bottom portion. The sliding seal member slides over the vertical engaging portion through the sliding groove and secures, utilizing at least one fastening means that inserts through the vertical groove on the vertical engaging portion. The base mount assembly further includes a covering means that is adaptable to securely cover the at least one tightening means on the elevated seal portion for providing waterproof sealing between the base mount assembly and the roof structure. 
     The clamp assembly comprises the clamp member that is coupled with the plate member. The clamp member includes a plurality of apertures on an inner surface thereof and a plurality of holes to receive a plurality of screws and the plate member that includes a plurality of slots. The plurality of apertures and the plurality of slots are oriented along a common longitudinal path to receive the at least one securing means. The at least one securing means is slid through the horizontal groove and inserted through the plurality of slots on the plate member and the plurality of apertures on the inner surface of the clamp member. Thus, the clamp member, the plate member and the top slider are secured to each other utilizing the at least one securing means. Thus, the plurality of PV modules are interlocked in a way to provide a corner-to-corner coupling arrangement which enables the connection of PV module corners to adjacent PV module corners by sandwiching above and beneath the frame members of the PV modules. 
     A first objective of the present invention is to provide a corner-to-corner coupling arrangement, enabling the bridging of a PV module corner directly with adjacent PV module corner. 
     A second objective of the present invention is to provide an efficient means of installation that does not require any additional material or structure to support the rail-less roof mounting system. 
     A third objective of the present invention is to provide a cost-effective means for PV modules installation. 
     A fourth objective of the present invention is to provide a rail-less roof mounting system that reduces dead load on a roof structure along with design engineering costs and hard and soft balance of system (BOS) costs. 
     A fifth objective of the present invention is to provide a rail-less roof mounting system that is lightweight and to provide improved engineering design to accommodate high snow and wind loads. 
     A sixth objective of the present invention is to provide a rail-less roof mounting system that allows an installer to easily work around roof obstructions like vents, skylights, and other roof protrusions. 
     A seventh objective of the present invention is to provide a rail-less roof mounting system that minimize the number of parts and tools needed to assemble and install the PV module. 
     An eighth objective of the present invention is to provide a rail-less roof mounting system that provides the ability to increase vertical leveling adjustability. 
     A ninth objective of the present invention is to provide a rail-less roof mounting system that independently removes a single PV module without deconstructing an entire row of the PV array. 
     Another objective of the present invention is to provide a rail-less roof mounting system that allows height adjustment of the rail-less roof mounting system after the installation of PV modules. 
     Yet another object of the present invention is to provide a rail-less roof mounting system that has a single grounding lug and a single point of penetration with an elevated seal portion for waterproofing the roof structure. 
     Still yet another object of the present invention is to provide a rail-less roof mounting system that retrofits into existing roofs without the need to cut shingles. 
     Yet still another object of the present invention is to provide a rail-less roof mounting system that eliminates the need to transport to the jobsite, configure and cut long heavy rails for installation purposes. 
     Still yet another object of the present invention is to provide a rail-less roof mounting system that can cantilever PV modules in portrait orientation, landscape orientation or a combination of both. 
     Yet still another object of the present invention is to provide a rail-less roof mounting system that employs a plurality of wire clips to work in multiple locations to minimize wire management issues. 
     These and other advantages and features of the present invention are described with specificity so as to make the present invention understandable to one of ordinary skill in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Elements in the figures have not necessarily been drawn to scale in order to enhance their clarity and improve understanding of these various elements and embodiments of the invention. Furthermore, elements that are known to be common and well understood to those in the industry are not depicted in order to provide a clear view of the various embodiments of the invention, thus the drawings are generalized in form in the interest of clarity and conciseness. 
         FIG.  1    illustrates a perspective view of a rail-less roof mounting system for installing a plurality of photovoltaic (PV) modules on a roof structure in accordance with the preferred embodiment of the present invention; 
         FIG.  2    illustrates an exploded view of a base mount assembly in accordance with the preferred embodiment of the present invention; 
         FIG.  3    illustrates an exploded view of a clamp assembly associated with the base mount assembly in accordance with the preferred embodiment of the present invention; 
         FIG.  4    illustrates a first mounting position of the rail-less roof mounting system interlocking the plurality of PV modules to form a corner-to-corner coupling arrangement in accordance with the preferred embodiment of the present invention; 
         FIG.  5    illustrates a second mounting position of the rail-less roof mounting system interlocking the plurality of PV modules to form the corner-to-corner coupling arrangement in accordance with the preferred embodiment of the present invention; 
         FIG.  6    illustrates the rail-less roof mounting system interlocking two PV modules in an arrangement in accordance with an alternate configuration of the present invention; 
         FIG.  7    illustrates installation of the rail-less roof mounting system on the roof structure in accordance with the preferred embodiment of the present invention; 
         FIG.  8    illustrates the base mount assembly configured to adjust mounting height of the rail-less roof mounting system in accordance with the preferred embodiment of the present invention; 
         FIG.  9    illustrates a perspective view of a PV array skirt providing a snap-fit engagement with the rail-less roof mounting system in accordance with the preferred embodiment of the present invention; 
         FIG.  10    illustrates a profile view of the PV array skirt providing the snap-fit engagement with the rail-less roof mounting system shown in  FIG.  9   ; 
         FIG.  11    illustrates a perspective view of interlocking of two PV array skirts in accordance with the preferred embodiment of the present invention; and 
         FIG.  12    illustrates one embodiment of a clamp assembly in accordance with the present invention and; 
         FIG.  13    illustrates an alternative embodiment of a skirt assembly in accordance with the present invention; 
         FIG.  14    illustrates an alternative embodiment of a skirt assembly in accordance with the present invention; 
         FIG.  15    illustrates an alternative embodiment wherein the corner-to-corner coupling arrangement is supported above the roof by the frame members of the PV modules; 
         FIG.  16    illustrates a plan view of multiple PV modules according to an embodiment of the invention, with multiple circles and corresponding figure numbers  19 A,  19 B,  20 A and  20 B identified as enlarged views; 
         FIG.  17    illustrates a plan view of multiple PV modules according to an embodiment of the invention, with multiple circles and corresponding figure numbers  21 ,  22 ,  23  and  24  identified as enlarged views; 
         FIG.  18    illustrates a plan view of multiple PV modules according to an embodiment of the invention, with multiple circles and corresponding figure numbers  19 A,  19 B,  20 A,  20 B,  21 ,  22 ,  23  and  24  identified as enlarged views; 
         FIGS.  19 A and  19 B  illustrate the enlarged portion shown in  FIGS.  16  and  18   ; 
         FIGS.  20 A and  20 B  illustrate the enlarged portion shown in  FIGS.  16  and  18   ; 
         FIG.  21    illustrates the enlarged portion shown in  FIG.  17   ; 
         FIG.  22    illustrates the enlarged portion shown in  FIG.  17   ; 
         FIG.  23    illustrates the enlarged portion shown in  FIGS.  17  and  18   ; and 
         FIG.  24    illustrates the enlarged portion shown in  FIGS.  17  and  18   . 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     In the following discussion that addresses a number of embodiments and applications of the present invention, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and changes may be made without departing from the scope of the present invention. 
     Various inventive features are described below that can each be used independently of one another or in combination with other features. However, any single inventive feature may not address any of the problems discussed above or only address one of the problems discussed above. Further, one or more of the problems discussed above may not be fully addressed by any of the features described below. 
     Turning now to  FIG.  1   , a perspective view of a rail-less roof mounting system  100  for installing a plurality of photovoltaic (PV) modules  170 ,  172 ,  174  (See  FIG.  4   ) on a roof structure  176  (See  FIGS.  7 ,  13 ,  14  and  15   ) in accordance with the preferred embodiment of the present invention is illustrated. The rail-less roof mounting system  100  comprises a base mount assembly  102  that is associated with a clamp assembly  144  to bridge the plurality of PV modules  170 ,  172 ,  174  and to install the plurality of PV modules  170 ,  172 ,  174  on the roof structure  176 . The base mount assembly  102  attached to the roof structure  176  comprises a base member  104  having a top surface  108  and a bottom surface (not shown), a block slider  110  having an elevated seal portion  112  (See  FIG.  2   ) and a vertical engaging portion  114  and a top slider  124  having a top portion  126  and a bottom portion  128 . 
     The clamp assembly  144  includes a clamp member  146  that is fixed with a plate member  148 . The rail-less roof mounting system  100  can be easily disassembled and hence provides a compact means of storage when not in use. The bottom surface (not shown) of the base member  102  is engaged with the roof structure  176 . The block slider  110  is connected with the base member  104  and with the bottom portion  128  of the top slider  124 . A track  130  having a horizontal groove  132  is included at the top portion  126  of the top slider  124  and a sliding seal member  134  having a sliding groove  136  and an opening  138  are included at the bottom portion  128  of the top slider  124 . The sliding seal member  134  is secured to the block slider  110  utilizing at least one fastening means  140 . The clamp member  146  and the plate member  148  are attached with the track  130  utilizing at least one securing means  150 . The clamp member  146  includes a plurality of apertures  154  (See  FIG.  10   ) on an inner surface  156  thereof and a plurality of holes  157  to receive a plurality of screws  178 . The plate member  148  includes a plurality of slots  152  to receive the at least one securing means  150 . The clamp member  146  is shown in further detail in  FIGS.  19 A,  19 B,  20 A,  20 B,  21 ,  22 ,  23 , and  24    as well as their position within the solar array in  FIGS.  16 ,  17  and  18   . 
       FIG.  2    illustrates an exploded view of the base mount assembly  102  in accordance with the preferred embodiment of the present invention. A waterproof means  106  is attached on the top surface  108  of the base member  104 . In the preferred embodiment, the base member  104  is made from an aluminum flashing. The bottom surface (not shown) of the base member  104  is engaged with the roof structure  176 . The elevated seal portion  112 , having a borehole  116  formed therethrough to receive the waterproof means  106 , engages with the base member  104  and the roof structure  176 , utilizing at least one tightening means  118  that is inserted through the borehole  116  and the waterproof means  106 . Then, the at least one tightening means  118  comes from the borehole  116  and the waterproof means  106  is drilled into the roof structure  176 . The base mount assembly  102  includes a covering means  142  that is adaptable to securely cover the at least one tightening means  118  on the elevated seal portion  112  for providing waterproof sealing between the base mount assembly  102  and the roof structure  176 . 
     The at least one tightening means  118  is of the type typically known in construction/installation and may comprise a structural screw having a head portion  218 . Specifically, the at least one tightening means  118  is a T-30/hex washer head lag screw. A sealing washer  158  is utilized for fitting on the at least one tightening means  118  and adapted to seal the borehole  116  in the elevated seal portion  112 , through which the at least one tightening means  118  is fitted, so as to prevent seepage of water. Preferably, the sealing washer  158  is an annular disc, which is deformable to create a tight seal. In one embodiment, the sealing washer  158  comprises a disk  258  of rigid material such as steel, with a section  259  or outer layer of deformable material that may be selected from a group consisting of: fluorinated silicone, polyurethane and rubber. Additionally, the sealing washer  158 , which is most likely to experience wear, is a simple, inexpensive part that can be replaced individually, as needed. 
     The vertical engaging portion  114  of the block slider  110  has a vertical groove  120  along the surface  122  thereof. The sliding seal member  134  of the top slider  124  slides over the vertical engaging portion  114  through the sliding groove  136  on the top slider  124  and secures to the block slider  110 , utilizing the at least one fastening means  140  that is inserted through the vertical groove  120  on the vertical engaging portion  114  and the opening  138  on the sliding seal member  134 . Preferably, the at least one fastening means  140  can be in the form of, for example, a cap screw or similar structures. The at least one fastening means  140  is securely tightened utilizing a lock nut  162 . Typically, the lock nut is a serrated flange hex nut. The base mount assembly  102  further includes a plurality of wire clips  163  for holding/retaining one or more wires (not shown) from/for each PV module  170 ,  172 ,  174  that is mounted to a building surface by the clamp member  146 . 
       FIG.  3    illustrates an exploded view of the clamp assembly  144  associated with the base mount assembly  102  in accordance with the preferred embodiment of the present invention. The clamp assembly  144  comprises the clamp member  146  that is coupled with the plate member  148 . The clamp member  146  includes a plurality of apertures  154  (See  FIG.  10   ) on an inner surface  156  thereof and a plurality of holes  157  to receive a plurality of screws  178 , and the plate member  148  includes a plurality of slots  152 . The plurality of apertures  154  and the plurality of slots  152  are oriented along a common longitudinal path to receive the at least one securing means  150 . 
     The clamp assembly  144  is assembled with the base mount assembly  102  when in use. The at least one securing means  150  is slid through the horizontal groove  132  and inserted through the plurality of slots  152  on the plate member  148  and the plurality of apertures  154  on the inner surface  156  of the clamp member  146 . Thus, the clamp member  146 , the plate member  148  and the top slider  124  are secured to each other utilizing the at least one securing means  150 . The at least one securing means  150  may comprise a cap screw. Preferably, the at least one securing means  150  is a stainless steel 5/16 “Ø×2” grade 18/8 machine bolt. While securing the clamp assembly  144  with the base mount assembly  102 , an engaging nut  160  and a plurality of retainer rings  161  are utilized with the at least one securing means  150  to provide a tight seal. Preferably, the plurality of retainer rings  161  is made of plastic and the engaging nut  160  is a hex nut. It is noted that the engaging nut  160  utilized with the at least one securing means  150  replaces the conventional brake and provides a tight, secure attachment between the clamp assembly  144  and the base mount assembly  102 . The least one securing means  150  is securely tightened utilizing the lock nut  162 . Specifically, the lock nut  162  is a serrated flange hex nut. 
     The clamp member  146  replaces the conventional brake and eliminates edge bridge/mid edge conflict. This clamp assembly  144  works both on top of the base mount assembly  102  as well as independently. Such clamp assembly  144  is adjustable to fit “off-the-shelf” available PV modules. Moreover, the clamp assembly  144  is adjustable to mount most standard size PV modules. Furthermore, the clamp assembly  144  can fit all types of framed and frameless PV modules. 
       FIG.  4    illustrates a first mounting position of the rail-less roof mounting system  100  interlocking the plurality of PV modules  170 ,  172 ,  174  to form a corner-to-corner coupling arrangement in accordance with the preferred embodiment of the present invention. The clamp member  146  interconnects the frame member  164  of the PV module  170  to the frame member  166  of the adjacent PV module  172 . The clamp member  146  is attached to the frame members  164 ,  166 ,  168  of the plurality of PV modules  170 ,  172 ,  174  by inserting a plurality of screws  178  into the plurality of holes  157  at a middle of a formed PV array. In the first mounting position, the clamp assembly  144  is coupled with the base mount assembly  102 , utilizing one of the securing means  150  that is inserted through one of the apertures  154  in the inner surface  156  of the clamp member  146  and one of the slots  152  on the plate member  148 . 
       FIG.  5    illustrates a second mounting position of the rail-less roof mounting system  100  interlocking the plurality of PV modules  170 ,  172 ,  174  to form the corner-to-corner coupling arrangement in accordance with the preferred embodiment of the present invention. The clamp member  146  interconnects the frame member  164  of the PV module  170  to the frame member  166  of the adjacent PV module  172 . In the second mounting position, the clamp assembly  144  is coupled with the base mount assembly  102  utilizing another securing means  150  that is inserted through another aperture  154  in the inner surface  156  of the clamp member  146  and another slot  152  on the plate member  148 . 
     For instance, the clamp member  146  interlocks corners of the frame members  164 ,  166 ,  168  of the plurality of PV modules  170 ,  172 ,  174  to form a corner-to-corner coupling arrangement as illustrated in  FIGS.  4  and  5   . Although the rail-less roof mounting system  100  is shown in  FIGS.  4  and  5    holding three PV modules  170 ,  172 ,  174 , it is noted that the at least one rail-less roof mounting system  100  can bridge four PV modules at the corners in any row and column configuration. Thus, the plurality of PV modules  170 ,  172 ,  174  are interlocked in a way to provide the corner-to-corner coupling arrangement which enables the connection of PV module corners to adjacent PV module corners by sandwiching above and beneath the frame members  164 ,  166 ,  168  of the plurality of PV modules  170 ,  172 ,  174 . Moreover, the clamp member  146  interlocks top and bottom surfaces of the frame members  164 ,  166 ,  168  of the plurality of PV modules  170 ,  172 ,  174  as shown in  FIGS.  4  and  5   . 
     In the preferred embodiment, the plurality of PV modules  170 ,  172 ,  174  provided is aluminum framed PV modules. However, while the present invention will be described for use with a framed PV module, the present invention is not so limited. Thus, it is within the scope of the present invention that rigid frameless PV modules, i.e. PV modules utilizing glass modules, may also be utilized to practice the present invention. In one embodiment, the corner-to corner coupling arrangement provides connection with other mounting and/or racking components and does not provide attachment or connection with any portion of the roof structure  176  such as waterproofing layers, structural rooftop layers or any/all cosmetic layers. 
       FIG.  6    illustrates the rail-less roof mounting system  100  interlocking two PV modules  192 ,  194  in accordance with an alternate configuration of the present invention. In this configuration, the rail-less roof mounting system  100  interlocks top and bottom surfaces of frame members of two adjacent PV modules  192 ,  194  at an end of a formed PV array. 
       FIG.  7    illustrates installation of the rail-less roof mounting system  100  on the roof structure  176  in accordance with the preferred embodiment of the present invention. The roof structure  176  serves as a mounting surface for the base mount assembly  102 . The base member  104  is placed on the roof structure  176  and the at least one tightening means  118  is inserted through the borehole  116 , the waterproof means  106  and a roof rafter 180 that is positioned just beneath a roofing material  182  and a roofing sheathing  184 . The illustrative installation provides a single point of penetration with the elevated seal portion  112  for providing waterproofing. A minimum embedment depth of 2½ inches is preferred. Typically, the at least one tightening means  118  is a GRK RSS rugged structural screw made of specially hardened steel to provide with high tensile, torque and shear strength. For example, the screw has a 5/16 inch nominal diameter underneath the sealing washer  158 , a minimum of torque screw to 13 ft-lb and may be made of hardened steel preferably with an all weather coating such as Climate™ coating. Furthermore, the roof structure  176  can include pre-stamped and/or pre-drilled pilot holes formed therein through which the at least one tightening means  118  can be inserted. For example, the pilot holes have a diameter of about ⅛ of an inch. More profitably, the rail-less roof mounting system  100  is easily and quickly installed with minimal tools, such as a ½ inch open-end box wrench and a ½ inch socket. 
     A method for installing a plurality of photovoltaic (PV) modules  170 ,  172 ,  174  on a roof structure  176  includes the following steps. Firstly, a rail-less roof mounting system  100  is provided for mounting the plurality of PV modules  170 ,  172 ,  174 . The base member  104  is placed on the roof structure  176  and the block slider  110  is positioned above the base member  104  by inserting the waterproof means  106  through the borehole  116  on the elevated seal portion  112 . The at least one tightening means  118  is inserted through the borehole  116  and the waterproof means  106  to secure the block slider  110  and the base member  104  with the roof structure  176 . The sliding seal member  134  is slid over the vertical engaging portion  114  through the sliding groove  136  on the top slider  124 . The at least one fastening means  140  is inserted through the vertical groove  120  on the vertical engaging portion  114  and the opening  138  on the top slider  124  to attach the top slider  124  to the block slider  110 . The at least one fastening means  140  is tightened utilizing the lock nut  162 . The at least one securing means  150  is slid through the horizontal groove  132  and inserted through the plurality of slots  152  on the plate member  148  and a plurality of apertures  154  on clamp member  146  to attach the clamp member  146  and the plate member  148  with the track  130  of the top slider  124 . The at least one securing means  150  is tightened utilizing the lock nut  162 . 
     Then, the clamp member  146  interconnects the frame member  164  of the PV module  170  to the frame member  166  of the adjacent PV module  172  to provide a corner-to-corner coupling arrangement. Finally, the clamp member  146  is attached with the frame member  164  of the PV module  170  by inserting a plurality of screws  178  into a plurality of holes  157  on the clamp member  146 . Thus, the corner-to-corner coupling arrangement enables the connection of PV module corners to adjacent PV module corners by sandwiching above and beneath the frame members  164 ,  166 ,  168  of the plurality of PV modules  170 ,  172 ,  174 . 
       FIG.  8    illustrates the base mount assembly  102  configured to adjust the mounting height of the rail-less roof mounting system  100  in accordance with the preferred embodiment of the present invention. The height of mounting of the rail-less roof mounting system  100  is adjusted by adjusting the position of the top slider  124  along the vertical engaging portion  114  of the block slider  110 . The top slider  124  can be moved along the vertical engaging portion  114  and can be secured at desired position or height by tightening the at least one fastening means  140  through the vertical groove  120  on the vertical engaging portion  114  and the opening  138  on the sliding seal member  134 . 
       FIGS.  9  and  10    illustrate perspective and profile views of a PV array skirt  186  providing a snap-fit engagement with the rail-less roof mounting system  100  in accordance with the preferred embodiment of the present invention. A PV array skirt  186  is installed on an edge of a PV array. The PV array skirt  186  may provide improved aesthetics, safety and structural performance. The PV array skirt  186  may partially or fully obscure air gap and mounting hardware located beneath the PV array. The PV array skirt  186  may allow for the snap-fit engagement of the PV array skirt  186  to the rail-less roof mounting system  100 . The rail-less roof mounting system  100  may also allow for the snap-fit engagement with the plurality of PV modules  170 ,  172 ,  174 . The snap-fit engagement between the PV array skirt  186  and the rail-less roof mounting system  100  is achieved by inserting an extrusion  188  of the PV array skirt  186  along a grooved edge  147  of the plate member  148 . Thus, the grooved edge  147  provides a seat for the extrusion  188  of the PV array skirt  186  to provide the snap-fit engagement. The snap-fit engagement provides a longer landing ability to the plate member  148  and an ability to easily clean out debris from under the PV array skirt  186 . 
       FIG.  11    illustrates a perspective view of interlocking of two PV array skirts  186  in accordance with the preferred embodiment of the present invention. The two PV array skirts  186  are placed end-to-end and ready to be interlocked together with a plurality of skirt clips  190 . The plurality of skirt clips  190  is adaptable to prevent the PV array skirt  186  from sagging. The PV array skirt  186  may be manufactured from bent metal and may snap onto the rail-less roof mounting system  100  via the grooved edge  147  of the plate member  148 . The rail-less roof mounting system  100  allows for vertical height adjustment therefore allowing for adjustment of height of the PV array skirt  186  above the roof structure  176  thus preventing the debris from entering the underlying air gap. A gap provided between the PV array skirt  186  and the frame member  164  may be sized in order to enable adequate room for installing the plurality of wire clips  163  or any other mounting structures. 
     The embodiments discussed above allow for portrait orientation, landscape orientation or a combination of both. In a portrait orientation, the PV array having each of the plurality of PV modules  170 ,  172 ,  174  oriented, with the longest axis of the plurality of PV modules  170 ,  172 ,  174  extend in a forward-rearward direction, which is typically the south-north direction. The plurality of PV modules  170 ,  172 ,  174  have long edges with length running in cross-slope direction. It is noted, however, that the plurality of PV modules  170 ,  172 ,  174  can alternatively be oriented in a landscape orientation, that is, with the longest axis of the plurality of PV modules  170 ,  172 ,  174  extending in a lateral or side-to-side direction which is typically the east-west direction. Thus, the above-disclosed rail-less roof mounting system  100  can be used for gable roofs, hip roofs and flat and low slope gable roofs. The plurality of PV modules  170 ,  172 ,  174  have short edges with width running in cross-slope direction. Further, the rail-less roof mounting system  100  has the ability to cantilever the plurality of PV modules  170 ,  172 ,  174  for both portrait and landscape orientation, for example, 13 inch cantilever portrait and 19 inch cantilever landscape. 
     The preferred embodiment reduces the number of parts, the size, and the cost of the parts, resulting in a total part count of approximately 151 (a 50% reduction) and a total mounting system hardware cost of $0.30/W retail (a 54% reduction). Further, the labor time to install the rail-less roof mounting system  100  is decreased by a minimum of 35%, which results in the reduction of installation times by over 55% as installation efficiencies grow. When the rail-less roof mounting system  100  is installed for bridging the plurality of PV modules  170 ,  172 ,  174 , it is revealed a decrease of around 47% in non-electrical installation hours. Additional system design and procurement soft-costs are reduced by 67%, when utilizing the system. 
       FIG.  12    illustrates one embodiment of a clamp assembly  196  in accordance with the present invention. The clamp assembly  196  is small in size and adaptable to use for end-clamping the plurality of PV modules  170 ,  172 ,  174 . The clamp assembly  196  includes a clamp member  198  and a plate member  200 . The clamp member  198  includes an aperture (not shown) on an inner surface  202  thereof and a pair of holes (not shown) to receive a pair of screws  204  and the plate member  200  includes a slot (not shown). The plate member  200  further includes a grooved edge  206  to accommodate the PV array skirt  186 . At least one securing means  208  is inserted through the aperture (not shown) of the clamp member  198  and the slot (not shown) of the plate member  200  to engage the clamp member  198  and the plate member  200 . The clamp assembly  196  and related components are shown in further detail in  FIGS.  19 A,  19 B,  20 A,  20 B,  21 ,  22 ,  23 , and  24    as well as their position within the solar array in  FIGS.  16 ,  17  and  18   . 
     The presently disclosed system is advantageous because it provides the corner-to-corner coupling arrangement, enabling the bridging of corners of the plurality of PV modules  170 ,  172 ,  174 . The rail-less roof mounting system  100  provides a single grounding lug for assembling the PV array consisting of 300 PV modules or less. Further, the rail-less roof mounting system  100  includes the plurality of wire clips  163 , which are designed to work in multiple locations to minimize wire management issues. The rail-less roof mounting system  100  allows for more customizability in the PV array shape by allowing the installer to easily work around roof obstructions like vents, skylights, and other roof protrusions This rail-less roof mounting system  100  provides the ability to increase vertical leveling adjustability, for instance, 3 inch to 5 inch. The rail-less roof mounting system  100  has the ability to independently remove a single PV module without deconstructing an entire row of the PV array and allow for easy mounting height adjustment after the plurality of PV modules  170 ,  172 ,  174  are installed. The rail-less roof mounting system  100  can be easily assembled and disassembled and the components can be laid flat for easy storage and shipping. Furthermore, the rail-less roof mounting system  100  would require less manpower to install and rework. 
     The foregoing description of the preferred embodiment of the present invention has been presented for the purpose 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 the above teachings. It is intended that the scope of the present invention to not be limited by this detailed description, but by the claims and the equivalents to the claims appended hereto.