Patent Publication Number: US-2019169852-A1

Title: Metal roof above sheathing ventilation system

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to roof ventilation systems, and more particularly, to a ventilated roofing system and method of construction assembled upon a roof structure which enables a flow of air between parallel roofing layers. 
     BACKGROUND 
     Improper building techniques are often the underlying culprit behind high energy costs, structural damage, and even health problems for the building inhabitants. Many of these problems are the direct result of improper ventilation. In the hot summer, direct sunlight overheats the roof, and creates a furnace effect in the attic. The air in the house, especially on the second floor if present, becomes unbearable. Excessive energy consumption from fans and air conditioning drives up electric bills. In the winter, condensation of humid air in the attic can lead to rotting of structural wood, deterioration of insulation, and result in mold and mildew leading to health problems. Finally, a lack of proper roof ventilation results in rapid aging of the roof, which may lead to leaks and home damage. 
     Various attempts have been made to address these problems. These attempts can be seen by example in several U.S. Pat. No. 3,797,180, issued in the name of Grange, discloses a ventilated roof construction system having a continuous corrugated baffle positioned between parallel roofing members. The baffle is provided to allow air flow from the fascia to the ridge to prevent the formation of ice dams. 
     U.S. Pat. No. 4,937,990, issued in the name of Paquette, discloses a ventilation system for roofs comprising an impermeable sheet having a series of openings on its surface and a series of roofing supports to provide a means to dry roofing insulation when there is a break in the vapor barrier protecting the insulation. 
     U.S. Pat. No. 6,780,099, issued in the name of Harper, discloses a roof ventilation system comprising a plurality of roof panels having an internal triangular shaped baffling for facilitating the flow of air from lower edge portions of the roof structure to the upper ridge portion. 
     U.S. Pat. No. 8,281,522, issued in the name of Hawryshko, discloses a roof ventilation system comprising a first sheathing layer and a second sheathing layer divided by a plurality of venting channels that are trapezoidal or angular in shape and each side panels of the vented channels have a plurality of vent openings to facilitate air flow. 
     Other solutions include ridge cap ventilators and roof construction, as can be seen by example in U.S. Pat. No. 5,022,314, issued in the name of Waggoner, which describes a roof ventilation apparatus and ventilation spacers for placement between fascia and roof sheathing, as can be seen by example in U.S. Pat. No. 5,361,551, which describes a ventilation spacer for roof construction. 
     While these devices may accomplish their specific intended purpose, each suffers from one or more disadvantages or deficiencies with respect to design, function, or effectiveness and none address the need for a solution of promoting appropriate ventilation utilizing metal roof panels. Accordingly, there is a need for a means by which roofing can be provided with complete and thorough ventilation in an effort to combat the above-mentioned problems. The development of the present invention substantially departs from the conventional solutions and in doing so fulfills this need. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing background, a spacer designed to be inserted between a roofing panel clip and the sheathing is provided for the purpose of creating a ventilation channel between the sheathing and the roof. The spacer includes a rigid body having a first end, a second end opposite the first end, a top surface extending between the first end and the second end, and a bottom surface extending between the first end and the second end and opposite the top surface, wherein the first and second ends define an outer perimeter around the rigid body that is rounded at each of the first and second ends. 
     The spacer also includes an outer wall extending downwardly from the bottom surface along the outer perimeter to an outer wall edge and an interior wall extending downwardly from the bottom surface to an inner wall edge and spaced inwardly from the outer wall. The outer wall and inner wall each have an exterior surface and an interior surface, with the outer wall edge and inner wall edge extending between their respective exterior and interior surfaces. In one embodiment, the inner wall edge and outer wall edge are coplanar. 
     The spacer further includes a primary fastener opening in the rigid body located between the first end and the second end, with the primary fastener opening extending from the top surface to the bottom surface and defining a primary fastener ridge. The primary fastener opening is sized and shaped to receive a roofing panel fastener. 
     The spacer has a configuration of openings and slots on the spacer to allow it to be used with a wide variety of panel clips. The opening for the fastener, the outer rim, and the walls of the spacer are designed to seal against the sheathing and provide tiers of protection to prevent water from contacting the fasteners. The spacers are designed to have lips, grooves, and recessed areas that coincide with the walls to accommodate stacking to allow for different channel heights without having to stock multiple spacer sizes. Also, the preferred embodiment of the spacer is rounded to prevent water from collecting along the edges of the spacer and instead flow down the slope of the roof. Finally, the spacer is specifically designed to have one spacer per panel clip. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention, reference is made to the following detailed description of embodiments considered in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a top perspective view of a spacer shim constructed in accordance with an embodiment of the present invention; 
         FIG. 2  is a bottom perspective view of the spacer shim shown in  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of the spacer shim shown in  FIG. 1  taken along the line  3 - 3  and looking in the direction of the arrow; 
         FIG. 4  is a top perspective view of two (2) spacer shims stacked together in accordance with an embodiment of the present invention; 
         FIG. 5  is a perspective view of the spacer shim shown in  FIG. 1  being used on roof sheathing and with a metal roof panel clip; 
         FIG. 6  is a cross-sectional view of the spacer shim shown in  FIG. 5  taken along the line  6 - 6  and looking in the direction of the arrow; and 
         FIG. 7  is a top perspective view of a spacer shim in accordance with another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The ensuing detailed description provides preferred exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the herein disclosed inventions. Rather, the ensuing detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments in accordance with the herein disclosed invention. It should be understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention, as set forth in the appended claims. 
     To aid in describing the invention, directional terms may be used in the specification and claims to describe portions of the present invention (e.g., upper, lower, left, right, etc.). These directional definitions are merely intended to assist in describing and claiming the invention and are not intended to limit the invention in any way. In addition, reference numerals that are introduced in the specification in association with a drawing figure may be repeated in one or more subsequent figures without additional description in the specification, in order to provide context for other features. 
       FIGS. 1 and 5  show, respectively, a roof above sheathing spacer shim (“spacer”)  100  in accordance with an embodiment of the present invention, and the spacer  100  used in an exemplary manner with a roof panel  136 , roof panel clip (“clip”)  140 , sheathing  138 , and a fastener  148 . As seen in  FIG. 1 , the spacer  100  is made from a single piece of material (e.g., composite, aluminum, steel, or other metal). The spacer  100  is designed to be inserted between the panel clip  140  and the sheathing  152  to create a ventilation channel  144  between the sheathing  152  and the roof. 
     More specifically, the spacer  100  of  FIG. 1  has a top surface  102  and a bottom surface  124 , with a configuration of openings and slots extending between the top and bottom surfaces  102 ,  124  to allow the spacer  100  to be used with a wide variety of panel clips  140 . Since the spacer  100  is specifically designed to have one spacer per panel clip  140 , the fastener  148  is preferably going to utilize the primary fastener opening  112 . The centrically aligned primary fastener opening  112  is designed with the consideration that in use in conjunction with a fastener  148 , the spacer  100  will not only be securely seated against the sheathing  138  but also will provide a fully supportive base for the entire dimensions of the panel clip  140 . 
     However, the preferred embodiment of the invention is further designed to be used in conjunction with a variety of panel clips  140  that may or may not have a centrically located opening for a fastener  148 . The spacer  100  has an elongated and typically but not limited as an oval shaped primary fastener opening  112  which extends depth-wise from the top surface  102  to the bottom surface  124  and centrally from the approximate middle of the spacer  100  to the side to allow for adjustment and proper seating of a clip  140  in conjunction with the clip&#39;s fastener opening. The preferred embodiment of the spacer  100  also has an alternate fastener opening  106  that is adjacent to the primary fastener opening  112  but on the opposite side to which the primary fastener opening  112  extends toward the outer wall  116  of the spacer  100 . The alternate fastener opening  106  serves as an additional option to allow the spacer  100  to be used with a variety of panel clips  140  that may or may not have a centrically located placement for the fastener  148 . Further, the spacer  100  has a minimum of two elongated slots  118  that are preferably but not limited to be located along the longitudinal central axis of the spacer  100 . The slots  118 , like the alternate fastener opening  106 , serve as additional options to allow the spacer  100  to be used with a variety of clips  140  that may or may not have a centrically located placement for the fastener  148  or have additional fasteners  148  that can be used for additional attachment and proper seating of the clip  140 . 
     The spacer  100 , as shown in  FIG. 1 , preferably has unobstructed openings  106 ,  112  and slots  118  extending from the top surface  102  to the bottom surface  124 . But it would be prudent to appreciate alternate embodiments of the invention that either possess openings and slots that are covered with a light plastic film or similar material or in the alternative, the openings  106 ,  112  and slots  118  are molded to completion wherein an amount of material from which the spacer is molded is left as a top surface of the openings  106 ,  112  and slots  118  to further promote the spacer&#39;s  100  design function of protecting the fastener  148 . 
     As shown in  FIGS. 2 and 3 , the spacer  100  has an inner wall  114 , central wall  104 , and outer wall  116  designed to seal against the sheathing  138  that extend downward from the bottom surface  124  of the spacer  100  and for the purpose of but not limited to providing tiers of protection to prevent water from contacting the fasteners  148 . The outer wall  116  is sized and shaped to be coextensive with the outer perimeter of the spacer  100 , the central wall  104  is spaced inwardly from the outer wall  116  and is sized and shaped to surround the openings  106 ,  122  and slots  118  of the spacer  100 , and the inner wall  114  is spaced inwardly from the central wall  104  and is positioned between the primary fastener opening  112  on one side, and the slots  118  and the alternate fastener opening  106  on the other side. The inner wall edge  115 , the central wall edge  105 , and the outer wall edge  117  are preferably coplanar with a bottom plane  128  to permit the spacer  100  to seat evenly on sheathing  138  and provide protection against water contacting the fastener(s)  148 . Further, the preferred embodiment of the invention shows that the central walls  104  and the outer walls  116  are completely enclosed along their perimeters. In an alternative embodiment, the central walls  104  and the outer walls  116  may have one or more openings, preferably on the downward slope end of the spacer  100  to permit any water that may have entered the spacer to exit. Also, the preferred embodiment of the spacer  100  is rounded to prevent water from collecting along the edges of the spacer  100  and instead flow down the slope of the roof. 
     The spacers  100  as shown in  FIGS. 1 and 3 , are designed to have an outer lip  108  that coincides with the outer wall  116  and an inner wall  114  and a central wall  114  that coincide with a recessed area  120  and a groove  110  respectively, to accommodate stacking (see  FIG. 4 ) and to allow for different channel heights without having to stock multiple spacer  100  sizes. The preferred embodiment of the invention is approximately but not limited to being ⅜ (0.375) inches in height  122  and when two spacers  100  are stacked together (one on top the other as depicted in  FIG. 4 ) the height of the combined spacers is approximately but not limited to ¾ (0.75) inches, which is optimal for above sheathing ventilation. 
     Referring to  FIG. 3 , in the preferred embodiment, the outer wall  116 , central wall  104  and inner wall  114  all have a wall height  150  that is the distance measured from the bottom surface  124  to the bottom plane  128  of the outer wall edge  117 , the central wall edge  115 , and the inner wall edge  105 . The outer wall  116  has an outer wall thickness  152  that is the distance measured between the exterior and interior surfaces of the outer wall  116 , the central wall  104  has a central wall thickness  154  that is the distance measured between the exterior and interior surfaces of the central wall  104 , and the inner wall  114  has an inner wall thickness  156  that is the distance measured between the exterior and interior surfaces of the inner wall  114 . The wall height  150  of the outer, central, and inner walls  116 ,  104 ,  114  is significantly greater than the walls&#39; respective thicknesses (i.e., outer, central, and inner wall thicknesses  152 ,  154 ,  156 ) to allow for ventilation between the outer, central, and inner walls  116 ,  104 ,  114 . Further, in embodiments where the central and outer walls  104 ,  116  have one or more openings to allow water to drain from underneath the spacer  100 , the high wall height  150  lessens the effects of surface tension between the bottom surface  124  and the roof sheathing, thereby further facilitating water drainage and ventilation. In a preferred embodiment, the outer, central, and inner walls  116 ,  104 ,  114  each have a height-to-thickness ratio of 2:1, and more preferably 4:1, to further the advantages discussed above while also ensuring the structural integrity of the spacer  100  and minimizing the amount of material used to make the spacer  100 . 
     As shown in  FIG. 3 , the spacer  100  has a spacer height  122  and a wall height  150  that is less than the spacer height  122 . The spacer  100  also has a thickness that is measured by the distance between the top surface  102  and the bottom surface  124 . Alternatively, the thickness of the spacer  100  may also be measured by the difference between the spacer height  122  and the wall height  150 . In a preferred embodiment, the spacer  100  has a height-to-thickness ratio of at least 4:1 (i.e., spacer height  122 ≥4(spacer height  122 −wall height  150 )) to ensure that there is sufficient ventilation under the bottom surface  124  of the spacer  100 . 
       FIG. 6  shows a cross-sectional view of the preferred embodiment of the spacer  100  being used with a roofing panel clip  140 , with the clip  140  having a centrically located opening for the fastener  148 .  FIG. 6  further shows the exemplary seating of the spacer  100  on the sheathing  138  and how the inner wall edge  105 , the central wall edge  115 , and the outer wall edge  117  are all coplanar (i.e., sharing the same bottom plane  128 ) and seat preferably evenly onto the sheathing  138 , creating the tiers of protection from water contacting the fastener  148 . 
     In the figures, elements that are similar to those of other embodiments of the present invention are represented by reference numerals increased by a value of 100. Such elements should be regarded as having the same function and features unless otherwise stated or depicted herein, and the discussion of such elements may therefore not be repeated for multiple embodiments. 
     Thus, embodiments of a spacer have been provided herein. In at least one embodiment, the inventive spacer may advantageously be functional in a wider range of operating conditions (e.g., roofing, wall, or other construction purpose) as compared to conventionally utilized spacers, thereby providing a spacer having improved functionality in a wider range of applications. 
     While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.