Abstract:
Disclosed is a system for improving the condensation resistance of metal roof penetrations. When environmental conditions are right, the curbs associated with metal roof penetrations can experience condensation on metal parts for which there is no thermal break. The disclosed system provides a mechanism to implement a thermal break to prevent the formation of condensation.

Description:
RELATED APPLICATION 
     This application claims the benefit of priority to U.S. Provisional Application No. 61/909,724 filed on Nov. 27, 2013. The disclosure of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to improving the condensation resistance of a metal roof penetration in accordance with principles of the present disclosure. 
     BACKGROUND 
     With the current design of metal roof curbs the sidewall configuration of the curb tends to have a thermal short circuit into the inside area of the building. This is caused by the continuance of the metal through the sidewall section from the outside to the inside. This can cause the inside surface of the metal curb to remain at a temperature below the dew point temperature that can lead to condensation forming on the inside surface, causing what appears to water leaks within the building. The current method of addressing this problem is to trim and retain the surrounding roof insulation which does not present a thermal-break in the curb wall. This method is labor intensive and the foam retaining rod used to secure the surrounding roof insulation can become dislodged. Moreover, the use of the retaining rod, in this fashion, often times does not result in a pleasing visual experience for the finished installation. 
     For the foregoing reasons, there is a need to eliminate the loss of heat from the interior surfaces so the surfaces remain at a temperature above the dew point so that condensation does not occur on any surface. 
     For the foregoing reasons, there is a need for an inexpensive alternative to trimming off of the excess roof insulation. 
     For the foregoing reasons, there is a need for an alternative to the trimming off of the roof insulation that provides a more aesthetically appealing appearance upon completion of the installation of the insulation. 
     SUMMARY 
     Curbs are constructed on metal roofs around skylights and mechanical equipment such as heating or air condition units, to divert rain precipitation around the unit. The curbs are usually constructed as a rectangle whose side walls are parallel to corresponding sides of the roof. 
     In an exemplary embodiment a system is disclosed to provide a thermal break to eliminate a thermal short circuit in the system to maintain a minimum surface temperature above the dew point for the conditions present, to provide a system to retain the surrounding roof insulation that is cost effective and provides for the above mentioned thermal break; to provide a cleaner, more aesthetically pleasing appearance to the surrounding roof insulation, to utilize an insulating retaining rod configured to secure the surrounding roof insulation within the configuration of components that eliminates the possible inadvertent release of the retaining rod and the insulation as presently experienced with existing systems. In addition, the disclosed embodiment provides an easier to install application of the foam retaining rod over current designs as well as a design that can be used with any metal roof curbs used to support mechanical units including HVAC units, fans, as well as other applications of skylights and roof hatches. 
     Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawings in which like numerals represent like components. The contents of this summary section are provided only as a simplified introduction to the disclosure, and are not intended to be used to limit the scope of the appended claims. 
     The contents of this summary section are provided only as a simplified introduction to the disclosure, and are not intended to be used to limit the scope of the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a cutaway view of an embodiment of a roof curb sidewall section; 
         FIG. 2  illustrates a cutaway view of an embodiment of a roof curb sidewall section detailing an insulation termination method; 
         FIG. 3  illustrates a cutaway view of an embodiment of a roof curb sidewall section detailing an alternative insulation termination method; 
         FIG. 4  illustrates an embodiment of the assembly of the thermal break and the side rail; and 
         FIG. 5  illustrates a cutaway view of an embodiment of the insulating assembly detailing the disclosed technology. 
     
    
    
     DETAILED DESCRIPTION 
     The following description is of various exemplary embodiments only, and is not intended to limit the scope, applicability or configuration of the present disclosure in any way. Rather, the following description is intended to provide a convenient illustration for implementing various embodiments including the best mode. As will become apparent, various changes may be made in the function and arrangement of the elements described in these embodiments without departing from the scope of the appended claims. 
     Metal buildings with metal roofs have become popular for commercial, industrial and warehousing uses. These buildings often require roof openings for skylights, fans, air conditioning units and the like. The installation of such equipment requires a roof curb for support. 
     Traditionally, roof curbs have been designed specifically and custom made to provide a relatively horizontal mounting structure for a particular rooftop appliance given the shape and pitch of a particular roof. Designing and building these traditional roof curbs, often formed from a singular piece of metal to uniquely accommodate a particular roof pitch, has been a laborious and time consuming task for roof curb manufacturers and rooftop appliance installers. 
     Turning now to  FIG. 1  which reveals a curb section  20  with reference to the interior and exterior of the curb and building structure. The roof curb sidewall section  24  is positioned past the cut edge  25  of the roof structure  26 . The roof insulation  28  wraps beneath the curb sidewall section  24  and is held in position by a clip element  30  at the curb sidewall section  24 . A layer of insulation  32  is also disposed against the interior surface  34  of the roof curb sidewall section  24 . A skylight  36  is positioned over the curb section to allow access of daylight and to prevent intrusion of moisture. This particular design, when environmental conditions are aligned will support the formation of condensation on metal surfaces proximate C 1 . When the condensation forms at this point many occupants of the building will characterize this as a leaking roof and seek roof repairs when in reality with the design identified under  FIG. 1  little can be done to prevent the formation of condensation other than to prevent the interior temperature and humidity from reaching the point where condensation forms. 
     Turning now to  FIG. 2  which reveals an alternative configuration which also suffers from the deficiency that condensation may form at C 2 . This design is similar in most respects as regards the metal roof curb  20  and skylight  36  detailed in  FIG. 1 , but instead employs an insulation retainer  40  to hold the roof insulation in position. 
       FIG. 3  illustrates a current method of trimming and retaining the surrounding roof insulation  28  which is quite labor intensive. In addition, this particular methodology results in an appearance that is less than desirable as roof insulation can fall out of the slot  42  that retains a flexible insulating rod  44  and the end of the insulation  46 . This configuration is also deficient in that it does not provide a thermal break and condensation can form at C 3 . 
     Turning now to  FIG. 4  which details an exemplary embodiment of an insulating assembly  50  comprising a side rail  52  inter-engaged with a thermal-break  54  segment for preventing the formation of condensation on roof curb installations. The thermal break element  54  is preferably comprised of an engineered plastic such as polyvinyl chloride (PVC), that is interlocked with a side rail  52  preferably comprised of an extruded aluminum. The thermal break element  54 , just as the name suggests, is an insulator and serves to limit the transfer of heat away from the interior to the exterior of the structure. 
     The thermal-break  54  horizontal segment  60  includes a slot  62  that engages and interlocks with an upwardly extending flange  64  on the first segment  66  of the side rail  52 . In addition, the second segment  68  of the side rail  52  includes a hard stop  70  that abuts the first terminating edge  72  of the thermal-break  54 . The vertical wall  74  of the thermal break  54  terminate at an upper edge  76  and in conjunction with the oppositely disposed upwardly extending second segment  68  of the side rail  52  forms a pocket  80  for positioning of a longitudinally extending insulating rod  84  (seen in  FIG. 5 ). The insulating rod  84  serves to limit the transfer of heat between the interior space of the structure and the ambient environment and in conjunction with the thermal-break  54  can substantially reduce the potential for the formation of condensation. The second segment  68  of the side rail  52  terminates at a bend  86  of greater than 90 degrees and traverses into the third segment  88  of the side rail. When installed, the third segment  88  will be penetrated by self-tapping screws that secure the insulating assembly  50  to the skylight or other feature installed on the curb  90 . The third segment  88  is bent downwardly at a corner  92  to form a fourth segment  94 . The fourth segment  94  at approximately mid-span includes a plurality of through holes  98 . The through holes  98  are used for passing mounting hardware  100  through the fourth segment  94  and to anchor the faced insulation  104  in place as best seen in  FIG. 5   
     The fourth segment  94  extends downwardly to a termination point  108  and turns outwardly at approximately a 90 degree angle to form a fifth segment  112 . The fifth segment  112 , like all of the prior segments, may be of any desired length to accommodate the desired configuration of the structure being secured to the curb. The fifth segment  112  extends to a termination point  116 . A sixth segment  118  extends downwardly from the termination point  116  at a preferred angle of approximately 75 degrees; however, other angles of departure are also appropriate depending upon the configuration of the structure secured to the roof. The sixth segment  118  further includes a plurality of longitudinally displaced through holes  120 . The through holes allow passage of securement hardware  124  to attach the entire side rail  52  and the entire insulating assembly  50  to the ribs  130  of, for example, standing seam metal roof panels  132 . 
       FIG. 5  illustrates an embodiment of the insulating assembly  50  in position beneath a domed skylight  140 . In application of the insulating assembly, first an appropriately sized opening is cut into the roof panels  132  of the structure. For example, in a standing seam roof the roof panel  132  will be cut on the interior side of the seams. Once the opening in the roof structure has been created, installation of the insulating assembly  50  can commence with the passage of securement hardware  124  through the longitudinally displaced through holes  120  in the sixth segment  118  of the insulating assembly  50 . This securement hardware  124  serves to not only secure the insulating assembly to the roof panels  132  but also to secure a flexible weather-seal  144  in position beneath the fifth and sixth segments  112 ,  118  to prevent intrusion of water into the structure. Multiple units of the securement hardware  124  secure the sixth segment  118  along the entire longitudinal length of the sixth segment  118 . Passing the hardware through the sixth segment  118  and into the rib  130  of the roof panel  132  facilitates a watertight seal and rigidly secures the insulating assembly to the roof structure. The fifth segment  112  preferably rests atop the panel ridge  148  and the weather-seal  144  thereby providing further support for the insulating assembly  50 . 
     Extending upwardly from the fifth segment  112  is the fourth vertical segment  94  through which attachment hardware  100  is passed to anchor the faced insulation  104  in position when installed. The faced insulation  104  must be adequately anchored in position or with the passage of time and minor building movements it will loosen and drop from its position thereby reducing the thermal efficiency of the dome installation. Prior to the installation of the domed skylight  140  an insulating rod  84  is positioned into the pocket  80 . The diameter of the insulating rod  84  is slightly greater than the width of the longitudinally extending pocket  80  thereby creating a compression fit for the insulating rod  84 . Once the domed skylight  140  is installed, the top of the insulating rod  84  will interfere with the skylight flange  160  and will compress slightly forming an airtight seal that will prevent the intrusion of outside air. 
     Next, the installer of the domed skylight  140 , or other roof feature, passes a threaded fastener  156  through the flange  160  of the dome  140  and into the third segment  88 . Positioned beneath the flange  160  of the dome  140  is a weather seal  164  that prevents the intrusion of air, and water, into the interior of the building. The passage of the threaded fasteners  156  will secure the weather seal  164  into position and prevent the intrusion of ambient air and moisture. 
     As previously noted, during installation of the domed skylight  140 , or other roof component, as seen in  FIG. 5 , an edge of the faced insulation  104  is wrapped upward for engagement with the securement hardware  100  through the fourth segment  94 . The insulation  104  is then wrapped tightly around the edge  180  of the roof panel that has been cut for the skylight opening and continues to run beneath the remaining roof panels to enhance the thermal efficiency of the structure. 
     Having shown and described various embodiments of the present invention, further adaptations of the methods and systems described herein may be accomplished by appropriate modifications by one of ordinary skill in the art without departing from the scope of the present invention. Several of such potential modifications have been mentioned, and others will be apparent to those skilled in the art. For instance, the examples, embodiments, geometries, materials, dimensions, ratios, steps, and the like discussed above are illustrative and are not required. Accordingly, the scope of the present invention should be considered in terms of the following claims and is understood not to be limited to the details of structure and operation shown and described in the specification and drawings.