Patent Publication Number: US-2017370091-A1

Title: Modular clearspan building, and modular building sections and construction methods therefor

Description:
PRIORITY CLAIM AND CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority to U.S. Provisional Patent Application Ser. No. 62/354,865 filed Jun. 27, 2016. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to modular buildings and, particularly, to modular building sections and techniques for constructing clearspan buildings. 
     2. Description of the Related Art 
     Modular construction utilizes individual, discrete building components that are manufactured offsite, such as in a factory, and delivered to a building site for final construction of the building. For example, individual wall sections may be manufactured at a factory and driven, via tractor trailers, to a building site to be assembled to form a complete building. Alternatively, individual sections of a house, such as a living room or kitchen, may be assembled offsite and delivered to a building site for assembly into a complete house. 
     Due to size and structural constraints, clearspan buildings, such as gymnasiums or auditoriums, which generally require high ceilings and large open spaces are difficult to construct modularly. Specifically, transporting large sections of such a building such as a portion of the wall and roof, to a building site is difficult. As a result, clearspan buildings are often manufactured using traditional on-site construction methods, or by only partially taking advantage of modular building techniques, with some of the potential benefits of such techniques being lost because of the roof and the walls being manufactured and shipped separately. 
     Moreover, when items intended to be newly housed by a clearspan building are already on the future building site, their removal from the site is often necessary during building construction. Such items may include inventory, vehicles, equipment, etc., which may be stored or in use on the planned building&#39;s floor space. This floor space may, for example, be defined by a concrete pad prepared in anticipation of the building itself being later added onto the pad. Furthermore, a convenient space may be unavailable for temporarily relocating those items during building construction. Regardless, temporary removal of such items during the construction period can be time-consuming, cost-prohibitive, and interrupt business operations. Therefore, it would be desirable to construct a modular clearspan building without necessitating removal from the building site of items the building is intended to house. 
     It would also be desirable to incorporate as many of the completed building&#39;s structural and operational features as is practicable, into the modular clearspan building sections as manufactured and shipped. Doing so can avoid scheduling delays and costs associated with incorporating such features subsequent to arrival or installation of the building sections at the construction site, and allows the building to be more easily and immediately completed. 
     SUMMARY 
     In addition to facilitating modular construction of buildings or rooms having high ceilings and defining large open spaces, a modular clearspan building according to the present disclosure beneficially provides modular building sections and techniques that address the above-mentioned issues. 
     The invention includes, in one form thereof, a modular building section having an installed state in which the building section defines the roof and opposing walls of a modular clearspan building. The building section includes a roof portion extending in a longitudinal direction between opposite first and second ends, and a pair of first and second legs. Each leg has an upper end and a lower end. The first leg is pivotally attached about a first pivot axis to the roof portion proximate the roof portion first end, and the second leg is pivotally attached about a second pivot axis to the roof portion proximate the roof portion second end. The first and second pivot axes are parallel to each other and spaced in the longitudinal direction. Each of the first and second legs has a stowed position in which the leg generally extends in the longitudinal direction and is in superposition with the roof portion, and an expanded position in which the leg depends from the roof portion and generally extends perpendicularly to the longitudinal direction. The first and second legs are moveable independently of each other from their respective stowed positions to their respective expanded positions under the influence of gravity during lifting of the roof portion. 
     In some embodiments of the modular building section, the roof portion is substantially rigid and in their stowed positions the first leg and the second leg are both disposed beneath the roof portion. 
     In some embodiments of the modular building section, the first leg and the second leg in their stowed positions are substantially co-planar. 
     In some embodiments of the modular building section, each leg has a free end at which the leg lower end terminates, and the distance between the pivot axis and the free end of each respective leg is no greater than one half the distance between the first and second pivot axes of the roof portion. 
     In some embodiments of the modular building section, the roof portion is articulated and comprises a pair of roof sections pivotally connected to each other about a roof pivot axis. The building section is adapted for selectively assuming, with the first and second legs in their stowed positions, a roof portion extended condition in which the first and second legs are disposed beneath the roof portion, and a folded configuration in which the roof sections are vertically stacked. The distance the roof portion extends in the longitudinal direction in the folded configuration is approximately one-half the distance that the roof portion extends in the longitudinal direction in the building section installed state, and the length of the building section in the folded configuration is comparatively reduced. Consequently, transportation or storage of the modular building section can be better accommodated. 
     In some embodiments of the modular building section, the roof portion is supported proximate the roof pivot axis during lifting of the roof portion, and in the building section installed state the roof sections define a roof portion apex along the roof pivot axis. 
     In some embodiments of the modular building section, the modular building section has an expanded state in which the first and second legs are in their expanded positions, and further includes a pair of expanding flanges. Each of the pair of expanding flanges is disposed proximate to one of the roof portion first and second ends and is engageable with the respective first or second leg and the roof portion. Each expanding flange is biased into an open position in which movement of the respective leg from its expanded position towards its stowed position is prevented through abutting engagement of the expanding flange, and each expanding flange is moveable from its open position through sliding engagement of the expanding flange into a depressed position in which movement of the respective leg into its expanded position is permitted. Consequently, the modular building section is retained in the expanded state. 
     In some embodiments of the modular building section, each expanding flange is pivotally connected to the roof portion, and is adapted to have abutting engagement and sliding engagement with the respective leg. 
     In some embodiments of the modular building section, each expanding flange has a free edge abuttingly engageable with the respective leg in the leg expanded position. 
     In some embodiments of the modular building section, each leg is pivotally attached to the roof portion at a location between the leg upper and lower ends, and the expanding flange abuttingly engages a portion of the respective leg between the upper end and the pivot axis. 
     In some embodiments of the modular building section, with the modular building section in an expanded state, each leg has a fully expanded position into which the leg is secured relative to the roof portion. 
     Another embodiment takes the form of a modular clearspan building comprising at least one aforementioned modular building section in an installed state. 
     In some embodiments of the modular clearspan building, the at least one modular building section has lateral edges, and the modular clearspan building comprises a plurality of laterally adjacent modular building sections in an installed state, the modular building sections interconnected along superposed lateral edges thereof. 
     Another embodiment takes the form of an aforementioned modular building section wherein, prior to the building section being in an installed state, the first and second legs comprise substantially finished wall portions of a modular clearspan building. 
     In some embodiments of the modular building section, the building section is manufactured and configured for transportation to a construction site with the roof portion and the legs defining substantially finished roof and wall portions, respectively, of a completed modular clearspan building. 
     In some embodiments of the modular building section, the roof portion and/or wall portions of the modular building section as delivered to a construction site include structural and/or operational features of a completed modular clearspan building. 
     In some embodiments of the modular building section, the structural and/or operational features are defined by componentry of the modular building section as delivered to a construction site and are selected from the group consisting of: interior siding, exterior siding, insulation, finished doors, windows, window trim, receptacles for part of an electrical system, wiring for part of an electrical system, fixtures for part of an electrical system, pipes for part of a plumbing system, fittings for part of a plumbing system, sprinkler system components, ducts for part of an HVAC system, registers for part of an HVAC system, and lighting system components. 
     In some embodiments of the modular building section, the modular building section includes a pair of ground-engaging wheels at least temporarily attached to and supporting the lower ends of the first and second legs during lifting of the roof portion, whereby dragging contact of the leg lower ends on the ground during lifting of the roof portion is prevented. 
     The invention also includes, in another form thereof, a method for constructing a modular clearspan building including the steps of: lifting a roof portion of a modular building section; allowing a pair of legs attached to the roof portion to pivotally move relative to the roof portion about parallel pivot axes independently of each other under the influence of gravity during the step of lifting, from substantially stowed positions beneath and substantially parallel with the roof portion to expanded positions in which the legs depend from the roof portion; slidably engaging an expanding flange pivotally connected to the roof portion with an upper portion of each respective leg during pivotal movement of the leg to move the expanding flange against a biasing force from an open position to a depressed position with the leg upper end; moving each leg upper end past a free end of the respective expanding flange in its depressed position and into an expanded position and allowing the biased expending flange to return to an open position; and automatically locking each leg in its respective expanded position by facilitating abutting engagement between the respective expanding flange free end in its open position and the leg upper end. 
     The invention also includes, in yet another form thereof, a method for constructing a modular clearspan building, including the steps of: providing at a construction site a plurality of modular building sections, each building section having a roof portion and pivotally legs defining substantially finished roof and wall portions, respectively, of a completed modular clearspan building, each building section including componentry defining structural and/or operational features of the completed clearspan building; lifting the roof portion of a first modular building section of the plurality of modular building sections; allowing a pair of legs attached to the roof portion of the first modular building section to pivotally move relative to the roof portion about parallel pivot axes independently of each other under the influence of gravity during the step of lifting, from substantially stowed positions beneath and substantially parallel with the roof portion to expanded positions in which the legs depend from the roof portion and define opposing walls of the completed clearspan building; installing the first building section by securing it into its intended position on the construction site; lifting the roof portion of a second modular building section of the plurality of modular building sections; allowing a pair of legs attached to the roof portion of the second modular building section to pivotally move relative to the roof portion about parallel pivot axes independently of each other under the influence of gravity during the step of lifting, from substantially stowed positions beneath and substantially parallel with the roof portion to expanded positions in which the legs depend from the roof portion and define opposing walls of the completed clearspan building; installing the second building section by securing it into its intended position on the construction site adjacent the first building section; and securing the first and second building sections together. 
     In some embodiments of the method for constructing a modular clearspan building, the method also includes the step of interconnecting at least some componentry of the first and second building sections that define structural and/or operational features of the completed clearspan building. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The various objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings. Although the drawings represent embodiments of the disclosed apparatus or system, the drawings are not necessarily to scale or to the same scale and certain features may be exaggerated or omitted in order to better illustrate and explain the present disclosure. Moreover, in any accompanying drawings that show sectional views, cross-hatching of various sectional elements may have been omitted for clarity. It is to be understood that this omission of cross-hatching is for the purpose of clarity in illustration only. 
         FIG. 1  is a perspective view of a modular building section according to a first exemplary embodiment according to the present disclosure; 
         FIG. 2  is a perspective view of the building section of  FIG. 1 ; 
         FIGS. 3-7  are perspective views depicting various steps in an exemplary process of erecting the building section of  FIGS. 1 and 2 ; 
         FIG. 8  is a schematic view of an exemplary embodiment of a locking mechanism having an expanding flange; 
         FIG. 9  is a side view of a modular building section according to a second exemplary embodiment according to the present disclosure in a folded configuration; 
         FIG. 10  is a side view of the modular building section of  FIG. 9  in an unfolded configuration wherein the articulated roof portion is in an extended condition; 
         FIG. 1  is a side view of the building section of  FIG. 9  as it is being elevated and partially erected, and approaching the building section expanded state; 
         FIG. 12  is a side view of the building section of  FIG. 9 , showing the building section in its expanded state; 
         FIGS. 13 and 14  are side perspective views of a modular building section according to a third exemplary embodiment according to the present disclosure; 
         FIG. 15  is a side view of a portion of the modular building section shown in  FIGS. 13 and 14 ; 
         FIG. 16  is a lower side perspective view of the modular building section shown in  FIGS. 13 and 14 ; 
         FIG. 17  is a lower interior perspective view of the modular building section shown in  FIGS. 13 and 14 ; 
         FIGS. 18 and 19  are views of the modular building section according to the third embodiment with legs in their stowed positions; and 
         FIGS. 20-22  are interior perspective views of the modular building sections shown in  FIGS. 17-19 , showing included structural and operational features for a finished building. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate preferred embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENT(S) 
     The invention is adaptable to various modifications and alternative forms, and the specific embodiments thereof shown by way of example in the drawings is herein described in detail. The exemplary embodiments of the present disclosure are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of the present disclosure. It should be understood, however, that the drawings and detailed description are not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. 
     In the exemplary embodiments described herein, a plurality of individual modular building sections are to be provided and connected together at a construction site to form a modular clearspan building. Some modular building section embodiments according to the present disclosure are manufactured and shipped with their roof portions providing a finished roof. The roofs of some such embodiments include roofing material, such as a continuous sheet of rubberized material, that extends over and is adhered to planar roof deck portions. Each roof deck portion may comprise a base layer of corrugated sheet metal affixed to the supporting rafters. Atop the corrugated sheet metal base layer is a first layer of wooden fiberboard sheet, atop which is a layer of 4 inch thick structural foam board. The roof decks of building section embodiments for use in modular clearspan buildings to be constructed in high wind regions preferably include a second layer of wooden fiberboard sheets secured atop the foam board. These layers are surrounded by a 2×6 inch wooden frame across which the above-mentioned roofing material extends between the eaves at opposite ends of the roof portion. Modular building sections manufactured and shipped with finished roofs will define a narrow gaps therebetween after being installed. Each gap is sealably covered with a continuous strip of roofing material that overlaps and is adhered to the roofs of adjacent building sections near their lateral edges, with the strip preferably extending the entire length of the gap. 
     Each building section according to the various embodiments herein described includes a roof portion including rafters which support a roof that, in some embodiments, is a roof substantially as described above. Each building section embodiment herein described also includes a pair of opposing, foldable legs pivotably connected to the roof portion near each longitudinal end of the building section. Each leg generally extends laterally the width of its building section and is pivotably connected to rafters that define part of the roof portion structure. The rafters support the roof of the building section, and are pivotably coupled to the legs at pivot points located near the eaves. 
     Referring to  FIG. 1 , a first exemplary building section embodiment manufactured in accordance with the present disclosure is shown generally at numeral  10 . Building section  10  is one of a plurality of modular building sections that are adjacently installed laterally side-by-side and connected to one another to form the roof and wall structure of a modular clearspan building. In  FIGS. 1 and 2 , building section  10  is shown in a collapsed state in which its opposing pair of legs  12  is folded beneath the substantially rigid roof portion  13  in a stowed position. Legs  12  are pivotally attached to rafters  14  of roof portion  13 , which support its roof  16 . At each end of the elongate roof portion  13 , legs  12  are pivotally attached to rafters  14  at laterally spaced pivot points  18 , through which a pivot axis  19  extends. 
     By rotating the legs  12  of the building section  10  inwardly about the parallel pivot axes  19 , the legs  12  are folded into their stowed positions wherein their interior sides interface the interior side of the roof portion  13 . In their stowed positions, legs  12  lie beneath and are substantially parallel with the roof portion  13 . The exterior side of the roof portion  13  defines the roof  16  of the building section  10 . Roof  16  has a roof ridge  28  that extends in a direction generally parallel with the pivot axes  19  and is generally centered therebetween. The pitch of the roof  16  (e.g., ¼ inch per foot) provides a roof portion  13  that is generally flat. The roof portion  13  is also elongate (e.g., usually at least 34 feet and up to a transportation limited maximum of 80 feet) and generally narrow (e.g., up to a transportation limited width of 16½ feet). 
     The distance between the free end  40  of each leg  12  and its pivot axis  19  is no greater than one half the distance between the two pivot axes  19  of the roof portion  13 , so that both legs  12  of a building section  10  substantially lie in a plane when they are folded into their stowed positions. The legs  12  are secured to the rafters  14  with removable brackets  42  into their stowed positions for storage and shipping of the building section  10 . With the legs  12  in their stowed positions, each individual building section  10  has a substantially flat, thin profile that allows for a plurality of the individual building sections  10  to be vertically superposed when loaded onto a trailer for transport via known tractor-trailer rigs. 
     During construction, the legs  12  of building section  10  are unsecured from their stowed positions by removing brackets  42  and are unfolded downwardly, away from the interior side of the roof portion  13  by allowing the legs  12  to rotate about their pivot axes  19  as the roof portion  13  is raised, as by forklifts  20  or a crane (not shown) through attached cables, as shown in  FIG. 3 . During elevation of the roof portion  13 , the legs  12  move downwardly about pivot points  18 . 
     According to one exemplary construction method, the building section  10  with its legs  12  secured in their stowed position is maneuvered into a position generally over the eventual footprint of its installed position, and rested on the floor space. In this position, the legs  12  are unsecured from their stowed positions and the roof portion  13  then raised, causing the legs  12  to swing downwardly under the influence of gravity. Referring to  FIGS. 4-6 , as the crane or forklifts  20  continue to raise the roof portion, legs  12  will continue to pivot downwardly under their own weight and the building section  10  will enter a building section expanded state in which legs  12  are generally vertically oriented. 
     In certain embodiments, wheels  44  (shown in  FIGS. 13-15 ) are removably attached to the free end  40  of each leg  12  at opposite lateral edges of the leg  12 . At each leg&#39;s free end  40 , the wheel&#39;s circumference extends beyond the leg&#39;s bottom edge and exterior side, thereby preventing damage to the legs  12  that might otherwise occur by their free ends  40  being dragged along the ground or the concrete pad while the legs are being unfolded or the building section  10  is being maneuvered in its expanded state. The wheels  44  may be installed at the factory prior to shipping the building section  10 , or installed at the construction site prior to unsecuring the legs  12  from their stowed positions. The wheels  44  may be detached from the legs  12  when placing the building section  10  into its installed position. 
     Once the building section reaches the building section expanded state and the legs  12  are substantially vertical, the legs  12  may be secured to a building pad or other supporting structure. The legs  12  may thereafter be secured into their expanded states, in which they are fixed relative to the roof portion  13 . Alternatively, the legs  12  may first be fixed into their extended positions, and leg free ends  40  thereafter placed and secured into their installed positions. 
     According to another construction method, the building section  10 , assuming its expanded state under the influence of gravity alone or with its legs  12  fixed into their extended positions, is lifted by a crane and positioned generally above its eventual footprint on the building floor space, on which items to be housed by the building are located. By this construction method, removal of the items from the footprint, much less the construction site, is unnecessary. The building section  10  is lowered into place over the items, and secured into its installed position as described above. In a variation of this construction method, the building section  10 , assuming its expanded state under the influence of gravity or with its legs  12  fixed into their extended positions, is supported by a crane above the floor space and moved laterally towards its installed position along the floor space and, in a straddling manner, over the items to be housed by the finished building. This variation of the construction may be preferable when constructing a clearspan building having relatively tall walls or which is to house tall items, while the items to be housed remain on the building floor space. 
     Building sections  10  can be secured into their installed positions by bolting the leg free ends  40  to spaced stanchions set into and projecting from the concrete pad. The legs  12  of adjacently installed building sections  10  can also be bolted together through their abutting lateral edges. 
     In certain embodiments, one or more expanding flanges  24  pivotably attached to the roof portion  13  is used to lock each leg  12  at least partially if not fully into its expanded state and temporarily prevent the leg from closing (i.e., folding inwardly) until the building&#39;s plurality of building sections  10  is fully secured into their respective installed positions and to each other. In one such embodiment, shown schematically in  FIG. 8 , each expanding flange  24  is biased open to prevent its associated leg  12  from closing. Specifically, referring to  FIG. 8 , each expanding flange  24  is biased to an open position by a respective biasing mechanism  22 . In certain embodiments, biasing mechanism  22  is a spring. Biasing mechanism  22  may be secured to the roof portion  13  to secure biasing mechanism  22  in position. Biasing mechanism  22  exerts a biasing force on its expanding flange  24  to force the expanding flange  24  to its open position, as indicated above. 
     In operation, as legs  12  pivot about pivot points  18 , the uppermost end  52  of each respective leg  12  contacts its associated expanding flange(s)  24 . As the leg  12  continues to rotate about its pivot point  18 , the weight-induced force exerted by the leg  12  against the expanding flange(s)  24  overcomes the biasing force of biasing mechanism  22 , depressing expanding flange(s)  24  in a direction toward roof  16  and allows leg  12  to pass by expanding flange free end(s)  26 . Once leg  12  has passed by its expanding flange free end  26 , biasing mechanism  22  forces expanding flange  24  back into the open position, shown in  FIG. 8 , thereby capturing the leg  12  in a position that prevents its pivoting, closing movement. The interactions of expanding flange free ends  26  with leg upper ends  52  prevent legs  12  from moving toward their stowed positions and helps retain building structure  10  in or near its fully expanded state. 
       FIGS. 9-12  depict modular building section  30 , a second building section embodiment according to the present disclosure. Building section  30  includes foldable legs  12  as described above and an articulated roof portion  46 . Except as indicated otherwise, building section  30  is substantially similar in structure and function to, and is erected by the same techniques as, building section  10 ; identical reference numerals have been used to identify their substantially identical or similar, corresponding components. Roof portion  46  of each building section  30  includes a pair of roof sections  32  whose respective rafters  36  are pivotally connected to each another at pivot point  34 , which defines roof pivot axis  48 . A pair of opposing legs  12  is connected to the pair of rafters  36  at pivot points  18  in a manner substantially similar to that described above with respect to building section  10 . 
     Roof sections  32  of building section  30  are relatively moveable components of the articulated (i.e., non-rigid) roof portion  46  that cooperate to reconfigure the building section  30  during construction of a clearspan building. In its installed position, roof portion  46  forms an apex  50  ( FIG. 11 ) at pivot point  34  from which the exterior side of each roof section  32  slopes downwardly along its length from roof ridge  28  towards its eaves, near legs  12 . Creation of the apex  50  is facilitated by bringing a pair of rafter flanges  38 , each located on opposite sides of the roof pivot axis  48  and having an inwardly tapering slope, into abutting contact with one another as shown in  FIGS. 11 and 12 . 
     As shown in  FIG. 9 , building section  30 , with its legs  12  in their stowed positions, can be folded about pivot point  34  into a folded configuration that is about one-half the length of the roof portion  46  as installed. This folded configuration better accommodates the transportation of relatively long building sections  30  on a tractor-trailer rig as described above with respect to building section  10 . Alternatively, building section  30  can be transported in a configuration substantially as shown in  FIG. 10 . Once at a construction site, building section  30  is unloaded from the tractor-trailer rig and, if in its folded configuration, its roof sections  32  are unfolded to place the building section in the unfolded configuration substantially as shown in  FIG. 10 ; i.e., roof sections  32  are unfolded by rotating them relative to each other about roof pivot axis  48 , such that the exterior sides of the roof sections  32  both generally face upward and place the roof portion  46  in an extended condition, with legs still in their stowed positions. The distance between the free end  40  of each leg  12  and its respective pivot axis  19  is no greater than the distance between that pivot axis  19  and the roof pivot axis  48 , so that legs  12  substantially lie in a plane when building section  30  is in the unfolded configuration shown in  FIG. 10  and legs  12  are folded into their stowed positions. Thus, legs  12  may be longer than as shown in  FIGS. 9-12 , resulting in an erected building of correspondingly greater height. 
     Transitioning from the view of  FIG. 10  to that of  FIG. 11 , with the roof portion  46  in its extended condition and legs  12  unsecured from their stowed positions, the roof portion  46  is lifted near pivot point  34  in the direction of arrow A using a crane, for example. Referring to  FIG. 11 , as the roof portion  46  of building section  30  is raised, its opposing roof sections  32  will rotate downwardly about the roof pivot axis  48  until rafter flanges  38  are brought into abutting contact with one another. At this point, further relative pivoting motion between roof sections  32  while lifting roof portion  46  is prevented, and the roof apex  50  becomes fully defined. Although one may choose to affix the abutting rafter flanges  38  to each other at this point, as by bolting them together, once the roof portion  46  of building section  30  is moved into this configuration, both roof sections  32  will rise as a single unit as the roof portion  46  is lifted higher and, the legs  12  will continue to rotate downwardly about pivot points  18  as described above with respect to building section  10 . 
     In  FIG. 12 , building section  30  is shown in an expanded state with legs  12  in their expanded positions. In some embodiments of building section  30 , expanding flanges  24  (described above with respect to building section  10 ) are used to maintain building section  30  partially if not fully in its expanded state. 
     Alternatively or additionally, in some modular building section embodiments the upper ends  52  of legs  12 , located above pivot points  18 , are bolted to rafter members  14 ,  54  to fully draw and securely fix legs  12  into their extended positions, wherein the building section is in a fully expanded state. In such embodiments, interfacing surfaces of each leg&#39;s upper end  52  and a rafter member  14 ,  54  are drawn together into abutting contact and securely clamped together by tightening interconnecting bolts extending therethrough (e.g., bolts  56  of  FIG. 11 ), thereby preventing there relative pivotal motion about pivot axes  19 , and locking the leg  12  into its fully expanded position. 
     Some modular building section embodiments according to the present disclosure are manufactured and shipped with legs  12  defining a skeleton or framework to which building walls may be attached during building construction. Examples of such embodiments are shown in  FIGS. 1-12 . The legs of such embodiments provide a wall-supporting structure, but are manufactured and shipped without walls, which are installed subsequent to installing the building sections. 
     Referring now to  FIGS. 13-22 , third embodiment building section  60  is manufactured and shipped to the construction site with a roof portion  74  providing a finished roof  16  substantially as described above and roof-supporting rafters  14 . Building section  60  also includes a pair of foldable legs  12  as described above. Except as indicated otherwise, building section  60  is substantially similar in structure and function to, and is erected by the same techniques as, building section  10  and/or  30 ; identical reference numerals have been used to identify their substantially identical or corresponding components. 
     Legs  12  of building section  60  as shipped and installed define substantially finished wall portions  62  of the clearspan building. The roof portion  74  and/or wall portion  62  are configured, in various embodiments of building section  60 , to include structural and operational features of the completed building. These features are installed during manufacture of the modular building sections  60  at the factory, and are therefore installed concurrently with the building sections  60 , during construction of the resulting building. 
     The wall portions  62  of an embodiment of building section  60  are defined by interior siding  64  and exterior siding  66  located on opposite sides of legs  12 . Wall portions  62  may be insulated, as by the provision of fiberglass batting or other suitable insulating material between the interior and exterior siding  64 ,  66 . As manufactured, building section  60  carries componentry of systems that comprise structural and/or operational features of the completed building. For example, building section  60  may include receptacles for part of an electrical system  68 ; pipes and/or fittings for part of a plumbing system, finished (e.g., painted) doors  72 , and/or windows and their associated trim; and/or ducts and/or registers for part of an HVAC system, some of which are not shown. 
     The roof portion  74  of an embodiment of building section  60  may include features such as, for example: wiring, components (e.g., lighting components  80 ), fixtures and/or receptacles for part of an electrical system  76 ; pipes and/or fittings for part of a plumbing system  82 ; safety system components (e.g., smoke or CO detectors and wiring, and sprinkler system components  84 ); and/or ducts and/or components for part of an HVAC system, some of which are not shown. 
     Referring to  FIGS. 18 and 19 , the structural and operational features incorporated into the roof portion  74  and/or wall portion(s)  62  of embodiments of building section  60  are positioned between its vertically superposed roof and wall portion(s) when legs  12  are in their stowed positions, as during shipping. Features carried by roof and wall portions  74 ,  62  of an individual building section  60  that comprise part of certain operational systems for the building (e.g., electrical wiring) may be interconnected or placed in an interconnection-ready state during manufacture of the individual building section  60 . Such embodiments of building section  60  can also facilitate the interconnections of certain system features between adjoining individual building sections  60  once they have been secured into their installed positions during construction of the building. 
     According to each of the above-described embodiments, the open ends of the erected clearspan building, between which the installed building sections are located, are closed or capped with a plurality of adjacent, interconnected, vertically-extending, planar end wall sections (not shown) of known configuration, whose heights are typically greater than that of roof apex  50 . These end wall sections may be finished with doors, siding, insulation, wiring, plumbing, and/or other componentry in situ, subsequent to their installation relative to building sections  10 ,  30 ,  60 . Alternatively, such components may be installed during manufacture of the end wall sections, which are shipped to the construction site in a substantially finished condition, with their structural/operational components interconnected as necessary at the time of installation. 
     While this invention has been described as having preferred designs, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.