System for enhancing the thermal resistance of roofs and walls of buildings

A system for insulating a building comprising a first layer of rolled insulation disposed atop a longitudinally extending upper chord of a roof truss, a purlin or a girt of a wall. Discrete insulating spacer members are intermittently disposed atop the first insulation layer and along the longitudinally extending chord, purlin or girt. A three sided bridge with a plurality of tab elements overlaying and contiguous with the insulating spacer members. A second layer of rolled insulation disposed atop the bridge and panel clips secured with a fastener extending through each of the second layer of insulation, bridge, insulating spacer member, first layer of insulation and upper chord.

TECHNICAL FIELD

This disclosure relates generally to the field of insulating roof and wall structures and related methods. More specifically, the disclosure relates to the field of insulating metal roofed and metal walled structures in both new and retrofit construction.

BACKGROUND

For decades insulation has been used in metal buildings to retard thermal transfer through the roof as well as the wall structures. Typical roof and wall insulation configurations use blanket insulation. The thermal resistance offered by the insulation is compromised when it is compressed or packed down. In conventional metal roof and wall insulation systems, when the roof structure is applied to the tops of the roof purlins, or the wall structure is applied to the gifts, the thick layer of blanket insulation is compressed, thus reducing the thermal resistance of the insulation system. In some areas of the conventional roof and wall systems, the compression of the insulation is so severe that a thermal short is created, thus substantially degrading the insulation properties of the insulation system.

The above references to the background art do not constitute an admission that the art forms part of the common general knowledge of a person of ordinary skill in the art. The above references are not intended to limit the application of insulating systems as disclosed herein.

SUMMARY

According to a first aspect, the present disclosure provides a system for insulating roofs and walls, the insulating system include a first layer of rolled insulation disposed atop a longitudinally extending roof purlin upper chord of a roof truss or wall girt. Disposed atop the first layer of insulation are discrete insulating bridge blocks or brackets, also referred to as spacer members, intermittently disposed atop the first insulating layer and along the longitudinally extending upper chord. Atop the insulating bridge blocks or brackets is a supplemental insulating element continuous with the longitudinally extending upper chord disposed atop the intermittently disposed insulating bridge blocks or brackets. Adjacent the supplement insulating element is a bridge that may include a plurality of upwardly extending tab elements, the bridge overlaying and contiguous with the supplemental insulating element.

A second layer of rolled insulation disposed atop and contiguous with the bridge is then interwoven into the roof insulating structure. A plurality of panel clips are then secured with fasteners through each of the second layer of insulation, bridge, supplemental insulating element, discrete bridge blocks or brackets, first layer of insulation and upper chord, the panel clips being intermittently disposed along the longitudinally extending upper chord.

A comparable configuration of insulating elements including layered insulation, discrete spacer members and a plurality of panel clips or fasteners are utilized to secure a wall panel to horizontally spaced building girts thereby providing a system that eliminates thermal transfer short circuits in the walls. Likewise, this disclosed configuration may also be utilized to retrofit an existing roof or wall structure with only slight modification.

DETAILED DESCRIPTION

A building roof and wall insulating system10, as seen inFIG. 1, comprises the installation of insulating elements within the roof and wall structural features of a building12. A roof structure14including roof decking or sheeting16that are supported by purlins18. Purlins are structural members in a roof that span parallel to the building eave20, and support the roof decking or sheeting16. Sandwiched between the purlins18and the roof decking16are insulating elements, of various embodiments, that will be described in greater detail below.

The insulating system10detailed herein is equally applicable to insulating a wall panel22of a building12to limit the transfer of heat. The structural features disclosed herein may also be utilized to retrofit an existing roof or wall to enhance the thermal resistance of the building. Supporting the wall panels22are girts24that work in conjunction with columns26and the wall panels22. The girts24are horizontal structural members in a framed wall that provide lateral support to the wall panels22, primarily to resist wind loads and to assist in the attachment of the wall panels22.

FIG. 2illustrates a first embodiment of a purlin18mounted insulating system10without including the installation of the insulating material.FIG. 2provides a view, without rolled insulation in place, of the components used to mount the roof clip28to the metal bridge30and the bridge in turn to the purlin18. As previously noted, the purlin18is a longitudinally extending horizontal structural member in a roof system. Secured to the upper horizontal flange34of the purlin18is an embodiment of a bracket32, also generically referred to as a spacer member, that separates the metal bridge30by a specified distance from the upper horizontal flange34of the purlin18. The separation distance provided by the bracket, or spacer member, provides an open space for uncompressed rolled insulation thereby maximizing the thermal efficiency of the insulating elements. When fully installed, two layers of insulation will be incorporated as shown inFIGS. 10 and 11.

The brackets32may be fabricated in varying heights to accommodate different thicknesses of insulation that are positioned between the bottom36of the metal bridge30and the upper horizontal flange34of the purlin18. In colder climates it may be preferred to increase the thickness of the insulation and therefore taller brackets32may be employed to accommodate the increased thickness.

As seen inFIG. 2the bracket32is a Z-shaped component with a lower flange38, a connecting span40and an upper flange42(obscured beneath the metal bridge30). The lower flange38includes at least one through hole, and preferably several, allowing for threaded attachments44to pass through the lower flange and into the upper horizontal flange34of the purlin18. The procedure for attaching the lower flange38of the bracket32to the upper flange of the purlin18is best seen inFIG. 13. In that Figure, an extension46on an electric drill48passes through a cutout50in the bridge30to allow the socket52to engage the threaded attachment44and to draw the threaded attachments44down tight against lower flange38, the first layer of insulation116(causing local deformation of the rolled insulation) and the upper horizontal flange34of the purlin18. Once the nut44is fully tightened, the socket and extension46are withdrawn back through the cutout. Prior to installing the metal bridge30in position atop the purlin18the upper flange42is secured to the metal bridge30with a plurality of threaded fasteners, or alternatively, the upper flange42is connected to the bridge30at the factory during fabrication by welding or by other means of mechanical fastening. As seen inFIG. 2, all bracket32designs preferably utilize one or more stiffener gussets33stamped into the bracket material at the junction of the connecting member40and the upper and lower flanges42,38.

FIG. 3reveals the first embodiment of the bridge bracket32, also shown inFIG. 2, whileFIG. 4reveals a second embodiment of the bracket60that includes two connecting spans66,68. This embodiment includes a lower flange62with a plurality of openings64as well as two horizontal upper flanges70,72. This embodiment can provide increased crush resistance as compared to the embodiment shown inFIG. 3, for the roof when heavy loads, from snow, are anticipated.FIG. 4also reveals a bridge30with upwardly extending tabs140that ensure the roof clips28are positioned so that a fastener passes through the base126of the roof clip28, the bridge30and then the upper flange42of the bracket32.FIG. 5reveals a third embodiment of the bridge bracket74that is triangular in shape for mounting to a wide upper flange34of a purlin18. This embodiment provides additional load carrying capacity as compared to the first bracket embodiment32. This third bracket embodiment74includes a triangular connecting span76along with upper and lower flanges78,80for mounting to the bridge30with threaded fasteners and to the purlin upper flange34at the bridge bracket's lower flange80. A fourth embodiment is shown inFIG. 6and details a bracket82with a bipod configuration. Two legs84,86support the bracket82and are fabricated with side flanges88,90that are secured to the upper flange of a purlin18(not shown).

In lieu of metal brackets, as discussed immediately above, an alternative to separating the bridge30and providing space for placement of the rolled insulation, which retains the roof clip28in position, from the purlins18is an insulating block, also generically referred to as a spacer member. Insulating blocks are preferably fabricated from high quality insulating materials, such as ASTM C578-Type VI extruded polystyrene. As seen inFIG. 10, the insulating blocks,96,104which can be of any specified height, are positioned atop the first layer of insulation116, thereby causing localized deformation of the rolled insulation, which is placed over the upper flange34of the purlin18. Atop the insulating block96rests the metal bridge30. Atop the bridge30is laid a second layer of insulation124that is locally compressed by the base126of the roof clip28.

FIG. 7details an embodiment of a portion of the insulating system10employing a plurality of clips28secured through a standard metal bridge30to other features of the insulating system and into the structural elements of the building. Also shown inFIG. 7is an insulating element96disposed beneath the metal bridge30and effectively surrounded on three sides by the top surface98of the bridge as well as the two side surfaces100,102. The insulating element96is preferably comprised of a foam type material with very low heat transfer characteristics but also possessing a sufficiently high resistance to compressive loads. An exemplary insulating element96is fabricated from extruded polystyrene satisfying the requirements of ASTM C578-Type VI to include approximately a 40 psi compressive strength and a thermal resistance of R-5/inch. Other materials with comparable characteristics may also satisfy the operational requirements for the insulating system10.

FIG. 8details yet another configuration of the insulating system shown inFIG. 7. This portion of the insulating system details a plurality of blocks104disposed beneath and monolithic with the insulating element96. The blocks104are configured to extend downwardly on an intermittent basis providing gaps106for through passage of insulation (not shown).FIG. 8reveals an insulating block104with a flat bottom108and canted sides110. The flat bottom108of the insulating block104will rest against and compress a layer of rolled insulation that is positioned over the upper flange34of a purlin18. The upper surface112of the insulating block104will rest against a lower surface of the insulating element96.

In the embodiment detailed inFIG. 9, block114comprises a rectangular configuration. The rectangular insulating blocks114are of a lesser dimension than the block embodiment104detailed inFIG. 8and locally compress less of the rolled insulation; however, the block embodiment shown inFIG. 9also has a reduced capacity to carry roof loads due to the lesser footprint surface area of the insulating blocks114. Likewise, the insulating blocks114are intermittently disposed providing gaps115for through passage of uncompressed insulation (not shown).

FIG. 10reveals a cross sectional view of the insulating system10. The cross sectional view shown inFIG. 10reveals a purlin18with an upper flange34. Positioned atop the upper flange34is a rolled layer of insulation116. This insulation preferably has thermal resistance of at least R-19 and preferably employs a downward looking face layer118. The layer of insulation116is positioned between the flange34of the purlin18and the bottom surface120of the insulating block104. Positioned atop and also covering the two sides100,102of the insulating element96is the metal bridge30.

Positioned atop the upper surface98of the metal bridge is a second layer of insulation124. This layer of insulation preferably has a thermal resistance equivalent to at least R-25. The layer of insulation124experiences localized compression between the base126of the clip28and the top surface98of the metal bridge30and to a lesser extent immediately adjacent the base126. The entire assembly of dual layers of insulation116,124, insulating block108and insulating element96is secured in position by passing a threaded fastener47through the base126the upper layer of insulation124, the insulating element96the block104, the lower layer of insulation116and into the upper flange34of the purlin18. When these components are fully installed as detailed above the roof panels16are secured to the roof clip tab130of the roof clip28to complete the roof installation.

Importantly, in place of the insulating block104and the insulating element96shown inFIG. 10, the brackets32,60,74,82may be employed to provide separation between the upper flange34of the purlin18and the base126of the clip28. As previously discussed, the brackets32,60,74,82may be of many different configurations and sizes to accommodate the desired thermal characteristics of the building.

FIG. 11details a perspective view of the insulating system10fully configured atop a building with the roof panels16secured in position.FIG. 11details the purlins18in position as roof structural features. Resting atop the upper flange34of the purlin18is the lower layer of insulation116. Resting atop the lower layer of insulation are intermittently spaced insulating blocks134. The blocks134depicted inFIG. 11utilize a triangular configuration that minimizes the amount of surface contact with the lower insulation layer116. This narrow line contact between the block134and the insulation serves to minimize the heat conduction path and increase the thermal efficiency of the building. Monolithic with, and disposed atop the insulating block134, is the insulating element96that can vary in thickness from less than inch to several inches depending upon the desired thermal efficiencies of the building.

Resting atop the insulating element96is the metal bridge30that provides further structural support to the insulating system10. The upper layer of rolled insulation124is positioned atop the metal bridge30and is rolled in a direction perpendicular to the purlin orientation, as best seen inFIG. 11. The roof clip28fastener47passes through the upper insulation124, the metal bridge30, insulating element96, insulating block134and lower insulation116and is secured to the purlin flange34.

FIG. 12provides another perspective view of the insulating system10showing the standing seam roof panels16engaged with the roof clip28and also detailing the two layers of insulation116,124, the metal bridge30, the insulating element96and the insulating block144.FIG. 13provides a perspective view of the insulating system10being installed. As detailed inFIG. 13, the metal bridge30utilizes basic Z-shaped brackets32. The brackets32are preferably attached to the underside of the metal bridge30during fabrication by welding or other means of mechanical fastening and come as an assembled unit in various bridge lengths with a four foot length being standard. As seen inFIG. 13, some bridges30utilizes a plurality of upwardly extending tabs140for quick and accurate placement of the roof clip28and to facilitate securing the roof clip28, the bridge30and the upper flange42of the bracket32together by passing a fastener through all three aligned components. Because the metal bridge30will often be overlain with the upper insulation layer124the installer may have difficulty locating the precise attachment point for the roof clip28. The tabs140allow for a precise methodology for alignment of the clips so that the roof clips28are located directly above the bridge supports (be they insulating blocks or metal brackets) and the roof panels16remain fully aligned across the span of the roof.

The above discussion is directed to the installation of an insulating system to roof of the structure but is equally applicable to the walls of a structure. The description set forth above and as further detailed below should not be construed as limiting the applicability of the insulating system to just roof structures. The disclosed system is also fully capable of insulating a wall of a structure that does not employ a girt but instead utilizes a substrate such as wood. The same insulating block or bracket system is secured to the building substrate and ultimately secured to a wall or roof panel and the disclosed system should not be viewed as constrained to metal pre-fabricated building components. The same insulating block or bracket system may be used to retrofit or reroof an existing building, and may not be secured directly to an existing roof deck or structural system.

The description of the installation of the insulating system10begins with a roof structure that is comprised of bare purlins18. A layer of rolled insulation116, preferably with facing layer118, is laid transversely across the purlins18. Next, depending upon the specifications of the building owner, a bracket32embodiment or an insulating block104,114embodiment is selected. An exemplary embodiment of a bracket assembly, as seen inFIG. 3is comprised of a bridge30with brackets32pre-welded or fastened with other mechanical means to the underside of the bridge30at the upper flange42of the bracket. The bracket also includes a lower flange38that extends outwardly and includes a plurality of holes for anchoring the bracket to the purlin18. The bridge with the plurality of intermittently spaced brackets32is positioned atop the layer of insulation116and locally compresses the insulation adjacent the brackets. Just beyond the lower flange38the insulation quickly expands to full thickness and also maximum thermal resistance until, moving laterally along the rolled insulation, the next bracket32is encountered where the insulation is again locally compressed. As best seen inFIG. 13, to secure the brackets32and bridge30to the upper flange34of the purlin at least one threaded fastener54is passed through the lower flange38, through the insulating layer116and into the upper flange34of the purlin. A power drill48is preferably employed with a long extension46and a socket52for efficiently rotating the threaded fastener44through the upper flange34of the purlin18. This process is repeated as necessary to secure all of the brackets32to the purlin flange34.

To span the entire roofing structure multiple bridge or bracket assemblies may be required. As seen inFIG. 4each bridge is fabricated with a tab152at one end and a slot150at the opposite end. The tab152of a first bridge engages the slot150of a second adjacent bridge tying the two bridges together and providing for a highly linear path for the roofing panels16when ultimately installed.

Once the bridge and bracket assemblies are installed a second layer of insulation124is laid transversely over the bridge30. This layer of insulation is preferably unfaced. Once this layer of insulation is in position the installer then manually locates the upwardly extending tabs140which may require the installer to manually relocate the insulation proximate the tabs140. The installer is clearing an opening for placement of the clip28. The bridge will preferably have a total of three tabs140at each location where the roof clip28is to be secured. The three tabs140positively locate the roof clip28and also prevent undesired rotation of the clip28that could create installation challenges when the roof clips are secured to the roof panels16. The three tabs140, as discussed above, also facilitate alignment of the through holes in the base126of the clip28with the hole in the upper flange42of the bracket32which is disposed directly beneath the bridge30. A threaded fastener47, as seen inFIG. 13is then passed through the base126of the roof clip28. The threaded fastener47extends through the bridge30thereby securing the roof clip28to the top flange42of the bracket32which in turn is secured to the upper flange34of the purlin18.

Once the clips28are in position the roof panels are then laid in position over the second or upper layer of insulation124. Alternatively an insulating spacer block may be applied over the secondary layer of insulation at the bridge locations adding a thermal resistance and support for the panel. The roof panels are then seamed along with the roof panel tabs130in position. This roof structure is configured to resist the transfer of heat and is also water resistant.

As an alternative to the use of the bracket32configuration, as disclosed inFIG. 10, insulating blocks may be employed immediately above the first layer of insulation116. The insulating blocks104and insulating element96are preferably monolithic in configuration but may optionally be separate and combined as specified. As the insulating blocks104are placed atop the insulation116, the insulation locally compresses adjacent the insulating blocks and expands a short distance away from the blocks returning to full thickness and thermal resistance. The insulating blocks, where the insulation is fully compressed atop the purlin upper flange34, serve to minimize the transfer of heat and increase the thermal efficiency of the roof or wall structure.

The insulating block104and insulating element96and bridge30are then covered by a second layer of insulation124and the roof clip28with associated panel clip tab130are positioned atop the bridge thereby locally compressing the second insulation layer124. The installer, as detailed above, must then pass a threaded fastener47through the bridge30, the base126of the roof clip28, through the insulating element96and insulating block104and into the upper flange34of the purlin18. The threaded fasteners effectively secure the insulating system10to the purlins18of the structure. Once the roof clips28are in position the roof panel tab130may be integrated into the standing seam roof of the structure as is commonly performed in the industry,