AU2007231818B2 - Roof assembly for a transportable building construction - Google Patents

Description

1 TITLE "A ROOF ASSEMBLY FOR A TRANSPORTABLE BUILDING CONSTRUCTION" FIELD OF THE INVENTION 5 The invention relates to a roof assembly for a transportable building construction. In particular, although not exclusively, the invention relates to a roof assembly for a modular transportable building construction. BACKGROUND TO THE INVENTION Conventional building techniques often employ precast structural 10 elements which are assembled to form modular assemblies prior to transportation to the building site for the construction of the building. This form of construction allows a large proportion of the building construction to be carried out in a factory with the modular building assemblies being transported to the construction site to form the building. This lowers the 15 cost of the construction process and reduces the time taken to form the building. However, one of the difficulties with this form of construction is transporting the modular assemblies from the factory to the construction site. Due to height restrictions when transporting the modular assemblies from the factory to the construction site (e.g. overpasses and legal considerations), it is 20 necessary to design the roof with approximately a 15 degree pitch to allow the modular assembly to be easily transported. This constraint limits the architect's and owner's creative freedom when designing the house and inevitably detracts from the aesthetics of the newly constructed house. 25 2 OBJECT OF THE INVENTION It is an object of the invention to overcome or at least alleviate one or more of the above problems and/or provide the consumer with a useful or commercial choice. 5 DISCLOSURE OF THE INVENTION In one form, although not necessarily the broadest or only form, the invention resides in a roof assembly for a transportable building construction comprising: a plurality of ceiling joists; and 10 at least one roof unit rotatably secured to at least one ceiling joist, the at least one roof unit formed from a plurality of rafters; wherein the at least one roof unit is moveable between a collapsed position whereby the plurality of rafters of the at least one roof unit lie in a plane substantially parallel to a plane that the plurality of ceiling joists lie in, and an 15 erected position whereby each of the plurality of rafters of the at least one roof unit extends entirely to an apex of the at least one roof unit. Further features of the invention will become apparent from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS 20 To assist in understanding the invention and to enable a person skilled in the art to put the invention into practical effect preferred embodiments of the invention will be described by way of example only with reference to the accompanying drawings, wherein: FIG 1 shows an exploded perspective view of a building formed from a 25 plurality of transportable building constructions according to an embodiment of 3 the invention; FIG 2 shows a perspective view of a transportable building construction according to an embodiment of the invention with a roof unit of the modular building construction in an assembled position; 5 FIG 3 shows an exploded partial perspective view of the transportable building construction shown in FIG 2; FIG 4 shows a perspective view of the transportable building construction shown in FIG 2 with the roof unit in a collapsed position; FIG 5 shows a perspective view of the transportable building construction 10 shown in FIG 2 with the roof unit in an intermediate position; FIG 6 shows a perspective view of a roof unit for a transportable building construction according to a further embodiment of the invention, the roof unit being in an assembled position; FIG 7 shows a perspective view of the roof unit shown in FIG 6 in a 15 collapsed position; FIG 8 shows a perspective view of the roof unit shown in FIG 6 in an intermediate position; FIG 9 shows a perspective view of the roof unit shown in FIG 6 in a further intermediate position; and 20 FIG. 10A shows a side view of the roof unit shown in FIG. 6 in a collapsed and erected position with a 33 degree roof pitch; FIG. 10 A shows a side view of the roof unit shown in FIG. 6 in a collapsed and erected position with a 25 degree roof pitch; 4 FIG 11 shows a perspective view of a roof unit for a transportable building construction according to a further embodiment of the invention, the roof unit being in a collapsed position; FIG 12 shows a perspective view of the roof unit of FIG 11 in an 5 intermediate position; and FIG 13 shows a perspective view of the roof unit of FIG 11 in an assembled position; FIG 14 shows a perspective view of the roof unit of FIG 11 in an assembled position; and 10 FIG. 15 shows an exploded perspective view of the roof unit shown in FIG. 14. DETAILED DESCRIPTION OF THE INVENTION FIG 1 shows an exploded perspective view of a building 1000 formed from a plurality of transportable building constructions 100 according to an 15 embodiment of the invention. FIG 2 shows a perspective view of a transportable building construction 100 according to an embodiment of the invention. The transportable building construction 100 is formed from a roof unit 110, a plurality of ceiling joists 120, a plurality of struts 130, wall modules 140 and a plurality of truss end assemblies 20 150. In FIG 2, the roof unit 110 of the transportable building construction 100 is in an erected position as will be discussed in greater detail below. Each wall module 140 is formed from a plurality of studs 141 and a plurality of noggings 142 as is known in the art. An end of each ceiling joist 120 5 is fastened to an upper end of a wall module 140 and extends to, and is fastened to, an opposing wall module 140. A plurality of strut brackets 210 extend from the ceiling joists 120 at intervals. Additionally, a plurality of rafter brackets 220 extend upwardly at 5 intervals along an end ceiling joist 120A, the end ceiling joist 120A extending along a top portion of a wall module 140. The roof unit 110 is formed from a plurality of rafters 111 and a plurality of roof purlins 112 connect the rafters 111. It should be appreciated that the roof purlins 112 may sit on top of the rafters 111 as shown or may sit in between the 10 rafters 111. Additionally, a roof member 113 is fastened to the roof purlins 112 to complete the roof unit 110. Roof member 113, in the form of a corrugated metal sheet, is shown in cut away in FIG 1. Struts 130 support the roof unit 110 at the desired roof pitch. Each strut 130 has an end rotatably secured to a respective strut bracket 210 and an 15 opposing end is securely fastened to a respective rafter 111. As shown in FIG 2, a series of struts 130 extend from respective strut brackets 210 located on each ceiling joist 120. The length of each series of struts 130 on each adjacent ceiling joist 120 increase in proportion to the distance the roof unit 110 is to be spaced from the ceiling joists. It should be 20 appreciated that by a person skilled in the art that the number of struts 130 utilised may be varied according to strength requirements in the design. Additionally, each rafter 111 is rotatably fastened to a rafter bracket 220 as will be discussed in greater detail below. Referring to the exploded perspective view of FIG 3, the transportable 25 building construction 100 further comprises a plurality of truss end assemblies 6 150 with each truss end assembly 150 being securely fastened to, and extending outwardly from the end ceiling joist 120A. Truss end assembly 150 has an upright support member 152 and a base support member 153. A top member 151 extends between the upright support 5 member 152 and the base support member 153. Also shown in greater detail in FIG 3, rafter brackets 220 extend upwardly at intervals along end ceiling joist 120A. As shown, each rafter bracket 220 has a slot 222 formed between two opposing arms 224 and a seat 223. A respective rafter 111 is received within the slot 222 of a respective rafter bracket 220. The 10 respective seat 223 is attached to the ceiling joist 120A to hold the rafter bracket 220 in position. Furthermore, each rafter bracket 220 has a series of fastening apertures 221 extending through opposing arms 224 of the slot 222. A bolt (not shown) is located through corresponding fastening apertures 221 on the opposing arms 15 and through the respective rafter 111 in order that rafter is rotatably mounted to the rafter bracket 220 and hence the ceiling joist 120A. Suitably, the bolt (not shown) may be located through different fastening apertures to change the distance between end ceiling joist 120A and the respective rafter 111. FIG 4 shows a perspective view of the transportable building construction 20 100 with the roof unit 110 in a collapsed position for transportation. As shown, the rafters 111 are positioned adjacent with the ceiling joists 120. Each rafter 111 is rotatably mounted to a respective rafter bracket 220. Furthermore, each strut 130 is rotatably mounted to a respective strut bracket 210. However, each strut 130 is not securely fastened to a respective 25 rafter 111 and, as such, each strut 130 lies adjacent ceiling joists 120. In this 7 way, the roof unit 110 has a substantially horizontal roof pitch when the roof unit 100 is in the collapsed position which allows the transportable building construction 100 to be conveniently and safely transported from a factory to a construction site. 5 FIG 5 shows a perspective view of the transportable building construction 100 with the roof unit 110 in an intermediate position between the collapsed position and the assembled position. As shown, each rafter 111 of the roof unit 110 is rotated about its respective rafter bracket 220 such that the roof unit 110 demonstrates a roof pitch greater than the designed roof pitch for the modular 10 building assembly 100. This allows each strut 130 to be rotated about a respective strut bracket 220 to allow each strut 130 to be orientated vertically. The roof unit 110 is then rotated by rotating each rafter 111 about a respective rafter bracket 220 such that each rafter 111 is positioned adjacent a top end of the respective struts 130. 15 Each rafter 111 is then securely fastened to a respective strut 130 and each rafter 111 is securely fastened to a respective top member 152 as previously discussed. Hence, the roof unit 110 is securely positioned in the erected position with each rafter 111 extending from adjacent a respective rafter bracket 220 to an 20 apex of the roof unit 110 as shown in FIG 2. The roof unit 110 of the transportable building construction 100 of the invention is rotatably with respect to the ceiling joists 120 in order that the roof unit 110 is moveable between a collapsed position for transportation as shown in FIG 4. and an erected position shown in FIG. 2. The transportable building 25 constructions 100 of the present invention may be designed with greater roof 8 pitches than conventional modular building assemblies. Greater roof pitches are able to be achieved through the use of the rafter brackets 220 that allow the roof unit 100 to lie in a plane that is parallel to a plane that the ceiling joists 120 lie in when the roof unit 110 is in the collapsed position. Furthermore, as each rafter 5 111 extends entirely from adjacent a respective rafter bracket 220 to an apex of the roof unit, it is possible to fix the roof member 113 to the roof unit 110 prior to transportation. This minimises labour and time requirements on site as it the roof unit 110 is fully assembled in a factory or the like. FIG 6 shows a perspective view of two roof unit 110A, 110B for a 10 transportable building construction according to a further embodiment of the invention, the roof unit 110 being in an assembled position. In this embodiment, the roof unit 110A is formed from roof rafters 111A extending from respective rafter brackets 220A whilst roof unit 110B is formed from roof rafters 111B extending from respective rafter brackets 220B. Roof 15 rafters 111 A and roof rafters 111 B about adjacent their joint apex. Furthermore, in this embodiment of roof units 110A, 110B, the struts 130A, 130B are rotatably fastened to respective rafters 111A, 111 B and securely fastened to respective strut brackets 210A, 210B extending from ceiling joists 120A, 120B. 20 Again, each set of rafters 111A, 111 B extend substantially from respective rafter brackets 220A, 220B to the apex. FIG 7 shows a perspective view of the roof units 11 0A and 11 OB shown in FIG 6 in the collapsed position. As before, each strut 130A, 130B and each rafter 111A, 111B lie in a plane substantially parallel to the ceiling joists 120 for 25 transport purposes.

9 As shown, rafters 111A are pivotally mounted to respective rafter brackets 220A of roof unit 110A at a distance from ceiling joist 120 less than a distance from which rafters 111 B of roof unit 11 OB are pivotally mounted to respective rafter brackets 220B. That is, the rafters 111A have a pivot point on the brackets 5 220A which is lower than a pivot point on rafter brackets that mount rafters 111 B. This arrangement allows respective rafters 111A of roof unit 11OA and rafters 111B of roof unit 11OB to each lie in a plane substantially parallel to a plane of the ceiling joists 120. FIG 8 shows a perspective view of the roof unit shown in FIG 6 in a first 10 intermediate position and FIG 9 shows a perspective view of the roof unit shown in FIG 6 in a further intermediate position. As before, the rafters 111A, 111 B are rotated about respective rafter brackets 220A, 220B until each respective roof member 11 OA, 11 OB meets the required roof pitch and struts 130A, 130B are rotated until they are orientated substantially vertically. 15 The struts 130A, 130B are then securely fastened to respective strut brackets 21 OA, 21 OB. The roof units 11 0A and 11 OB are thus securely fastened in the erected position. FIG. 10A, 1OB and 1OC show a side view of a roof units 110A and 11OB for a transportable building construction as shown in FIG.6 with the roof units 20 110A and 11OB having different roof pitches. Each of the FIG. 1OA, 1OB and 10C shows the roof units 11OA and 11OB in both the collapsed and erected positions. FIG. 10A shows the roof units 110A and 11OB having a roof pitch of 33 degrees with respect to the ceiling joist 120. In order to obtain this pitch, the 25 rafter 111 B is rotatably mounted to a top aperture of the rafter bracket 220B.

10 This allows the roof member 113 to abut against the facia board 300B. Further, this allows the roof member to be located adjacent the gutter 301B. Similarly, rafter 111A is rotatably mounted to rafter bracket 220A. The roof member 113 abuts against the facia board 300A. Further, the roof member 5 is located adjacent the gutter 301A. FIG. 1OB shows the roof units 110A and 11OB having a roof pitch of 25 degrees with respect to the ceiling joist 120. In order to change the roof pitch from 33 degree to 25 degrees, rafter 111 B is moved from the top aperture of the rafter bracket 220B to the middle aperture of the rafter bracket 220B. This allow 10 the pitch to be changed but also to allow the roof member 113 to abut against the facia board 300B and the roof member 113 to be located adjacent the gutter 301 B. In order to change the pitch of the roof rafter 111A, the facia board 300A and gutter 301A is moved with respect to the truss end assembly. This allows 15 the roof rafter 11 1A to abut against the facia board 300A. Further, this allows the roof rafter 111A to be located adjacent the gutter 301A. It should be noted that the position of roof rafter in bracket 220A remains unchanged. This allows the roof member 113 to abut against the facia board 300B. Further, this allows the roof member to be located adjacent the gutter 301 B. 20 FIG 11 shows a perspective view of a roof unit 110 for a transportable building construction according to a further embodiment of the invention, the roof unit 110 being in an erected position. FIG 12 shows a perspective view of the roof unit 110 in an intermediate position and FIG 13 and 14 shows a perspective view of the roof unit 110 in an erected position.

11 In this embodiment, there are three roof units 110A, 11OB and 110C. As before, each rafter 111A, 111 B and 111 C extends substantially adjacent from an end ceiling joist to an apex when the roof units are in the erected position as shown. 5 As shown, rafters 111A are pivotally mounted to respective rafter brackets 220A of roof unit 110A at a distance from ceiling joist 120 less than a distance from which rafters 111B and 111B of respective roof unit 11OB and 111C are pivotally mounted to respective rafter brackets 220B and 220C. . That is, the rafters 111A have a pivot point on the brackets 220A which is lower than a pivot 10 point on rafter brackets 220B and 220C that mount rafters 111B and 111C. This allows each roof unit 110A, 11OB and 110C lie in a plane substantially parallel with a plane of the ceiling joists 120 when the roof unit 110 is in the collapsed position. FIG 15 shows a more details view of hip beams 400 that join roof units 15 110A and 11OB and roof units 110A and 110C. The hip beams 400 are formed from two hip beam portions 401A and 401B. Each of the hip beam portions 401A and 401B are U-shaped so that they are able to be connected easily to respect rafters 111A, 111B and 111C. As the hip beams 400 are split into two hip beam portions 401A and 401B, the roof units are able to be moved from 20 between a collapsed position to an erected position easily. As discussed, as the roof unit forming part of the transportable building construction is rotatable between a collapsed position, for transport, and an assembled position, the roof pitch of the roof unit may be designed to be greater than conventional modular building assemblies as no consideration as to 12 transport issues needs to be entered into when determining roof pitch when designing a building. This provides builders and home owners with greater flexibility and choice as to their desired roof pitch and increases the aesthetic qualities of buildings 5 constructed using modular building assemblies that are transported from the factory to a construction site. Throughout the specification the aim has been to describe the invention without limiting the invention to any one embodiment or specific collection of features. Persons skilled in the relevant art may realize variations from the 10 specific embodiments that will nonetheless fall within the scope of the invention. It will be appreciated that various other changes and modifications may be made to the embodiment described without departing from the spirit and scope of the invention.

Claims (5)

1. A roof assembly for a transportable building construction comprising: at least one ceiling joist including a first end and a second end; and a first roof unit and a second roof unit, each roof unit formed from a 5 plurality of rafters; wherein each roof unit is moveable between a collapsed position whereby the plurality of rafters of each roof unit lie in a plane substantially parallel to a plane in which the at least one joist lies in, and an erected position whereby each of the plurality of rafters of each roof unit extends entirely to an apex of each roof 10 unit; and wherein the first roof unit is rotatably mounted to the first end of the at least one ceiling joist at a first fixed pivot point above the at least one ceiling joist and the second roof unit is rotatably mounted to the second end of the at least one ceiling joist at a second fixed pivot point above the at least one ceiling joist, 15 the first pivot point being lower than the second pivot point.

2. The roof assembly of claim 1, each roof unit has a plurality of roof purlins extending transversely across at least two rafters, each roof unit further comprising a roof member securely fastened to the plurality of roof purlins. 20

3. The roof assembly of claim 1, wherein each rafter is rotatably secured to an end of a ceiling joist by way of a respective rafter bracket extending upwardly from the end of each ceiling joist. 25

4. The roof assembly of claim 3, wherein each rafter bracket is formed from a 14 seat and slot and a series of fastening apertures extending through opposing arms of the slot such that a respective rafter is receivable within the slot and rotatably mounted therein by way of a fastener extending through corresponding fastening apertures and the rafter. 5

5. The roof assembly of claim 1, wherein the plane in which the first roof unit lies when the roof unit is in the collapsed position is between the plane in which the second roof unit lies and the at least one ceiling joist. 10