1 TITLE WALL CONNECTION ARRANGEMENT AND METHOD CROSS-REFERENCE TO RELATED APPLICATIONS 5 This application is related to Australian Provisional Patent Application No 2009900780 for the above-titled invention, filed on behalf of the present applicant on 23 February 2009. BACKGROUND OF THE INVENTION 10 Field of the Invention The present invention relates to the construction of buildings, particularly although not exclusively, to the manufacture and assembly of the walls of pre-fabricated domestic buildings suited to flat packaging for transportation purposes. 15 Discussion of the Background Art Pre-fabricated, flat packaged domestic buildings, such as cabins, studios, pool houses, storage sheds and kit houses employ in one form a double tongue and 20 board timber board wall construction. These boards are similar to a conventional floor board, but with an extra tongue and groove, being around 140mm wide and ranging in thickness from 18mm to 70mm depending on the size of the structure. Instead of a conventional timber stud frame for support, external cladding for protection of the stud frame from prevailing weather and internal lining such as 25 plasterboard or plywood, these pre-fabricated buildings involve standing the double tongue and grove boards on edge, similar to a log cabin style construction. One method of construction of such buildings is to half-check or lap the external and internal corners of the timber boards in the style of log cabins. The result being that 30 the boards are locked into one another at the corners, marrying one wall to an adjacent wall via half-check joints. Whilst this is a strong method of construction when it comes to corners, door and windows fixtures are typically only nailed. Accordingly, the building structure is not uniformly tied together, notwithstanding the 2 time and effort expended in joining the corners. Furthermore, the half-checked corner construction may be, in many eyes, not aesthetically pleasing. The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that the referenced prior art forms 5 part of the common general knowledge in Australia. SUMMARY OF THE INVENTION Object of the Invention 10 The present invention aims to provide an alternative to existing arrangements for connecting walls to one another, which is simple, more efficient in construction, strong, cost effective and/or more aesthetically pleasing. Disclosure of the Invention 15 In one broad aspect, the invention resides in a connection arrangement for a wall of a building construction, said connection arrangement comprising: an elongate structural member including at least one longitudinal channel in a first section of the elongate member, said longitudinal channel having a continuous 20 mouth defined by opposed flanges forming a first face in the first section; and a connection formation having a cross-sectional shape substantially complementary to said at least one longitudinal channel, said connection formation including a head portion and a tail portion for fixing to wall element(s); wherein the head portion of the formation is adapted for slidable retention in 25 the longitudinal channel such that the tail portion protrudes between said opposed flanges and outwardly through said mouth; and whereby, in use, wall element(s) may be secured at one end adjacent to the first section of the elongate structural member. 30 The connection formation may comprise, in one form, a series of spaced fasteners, each fastener having a tail or shaft portion and an enlarged head portion. In another form the connection formation may comprise a continuous profile, suitably of substantially "T" shaped cross-section.
3 The wall element(s) suitably comprise a wall panel or a plurality of wall boards, which wall boards are desirably configured for inter-fitting lateral arrangement relative to the elongate structural member. 5 In another broad aspect, there is provided a connection arrangement for a wall of a building construction, said connection arrangement comprising: an elongate structural member including at least one longitudinal channel in a first section of the elongate member, said longitudinal channel having a continuous mouth defined by opposed flanges forming the first face of the first section; 10 a spaced series of fasteners for fixing to a plurality of wall boards, each said fastener having a shaft portion and an enlarged head portion; wherein the enlarged head portion of each fastener is adapted for slidable retention within the longitudinal channel such that the shaft portion protrudes between said opposed flanges and outwardly through said mouth; and 15 whereby, in use, the plurality of wall boards may be secured at one end adjacent to the first section of the elongate structural member. Desirably said opposed flanges include outer flanges and inner flanges, wherein the inner flanges are provided for engagement by the enlarged head portions of the 20 fasteners and the outer flanges, which outer flanges may be substantially normal to or parallel with said inner flanges, and at least one of the outer flanges is provided for engagement by at least one major surface of each of the plurality of wall boards. In one particularly preferred form, the inner flanges are arranged in edge-wise opposing relation and the outer flanges are arranged in face-wise opposing relation to one 25 another. Preferably a second section of the elongate structural member includes another longitudinal channel, wherein the elongate structural member forms a corner post or an intermediate/joining post for walls. If required, the elongate structural member 30 can include a third section having a further longitudinal channel, wherein the elongate structural member forms a wall intersection post.
4 Suitably the wall boards are adapted to extend laterally from said elongate structural member wherein spaced fasteners are secured in respective ends of said wall boards. The wall boards are preferably of cooperating tongue and groove configuration, more preferably of double tongue and double groove configuration. 5 In a further preferred form, one or more sections of the elongate structural member may include primary and secondary longitudinal channels, wherein the primary channel is provided for retaining a first series of fasteners fixed to external cladding and the secondary channel is provided for retaining a second series of fasteners 10 fixed to internal wall lining. Suitably the primary and secondary channels are in substantially parallel relation with one another. In further broad aspect, there is provided a connection arrangement for a wall of a building construction, said connection arrangement comprising: 15 an elongate structural member including at least one longitudinal channel in a first section of the elongate member, said longitudinal channel having a continuous mouth defined by opposed flanges forming a first face in the first section; a connection profile of substantially T-shaped cross-section for fixing to an edge of a wall panel, said connection profile having a tail portion and a head portion; 20 wherein the head portion of the connection profile is adapted for slidable retention within the longitudinal channel such that the tail portion of the profile protrudes between said opposed flanges and outwardly through said mouth; and whereby, in use, the wall panel may be secured at one end adjacent to the first section of the elongate structural member. 25 In a further preferred form wherein the wall panel comprises external cladding and internal lining, the T shaped profile is continuous and includes at its tail portion a fixing arrangement; the fixing arrangement providing an obverse surface for fixing to the external cladding and providing a reverse surface for fixing to the internal wall 30 lining. Most preferably, the fixing arrangement includes a tubular profile integrally formed with the T shaped cross-section of the continuous profile whereby a void may be provided between the external cladding and the internal lining of the wall panel.
5 The elongate structural member preferably takes the form of a post or a frame for a door or window jamb, is suitably tubular and composed of a metallic substance formed by extrusion, most suitably of aluminium. The post may be any one of an intermediate connecting post, a corner post or a wall intersection post, wherein the 5 intermediate connecting and corner posts include two sections, whilst the wall intersection post includes three sections. In another aspect of the invention there is provided a wall of a building construction, said wall comprising: 10 at least first and second elongate structural members in upright spaced relation to one another; each elongate member including at least one longitudinal channel in a first section of a respective elongate member, said longitudinal channels each having a continuous mouth defined by opposed flanges forming respective faces of the first 15 and second elongate structural members; a plurality of wall elements adapted for spanning the spaced elongate structural members; connection formations for fixing to each end of the wall elements, the connection formations having a tail portion and a head portion; 20 wherein the head portion of the connection formations is adapted for slidable retention in the longitudinal channel such that the tail portion protrudes between said opposed flanges and outwardly through said mouth; and whereby the wall elements are secured at each end adjacent to respective faces of the first and second elongate structural members. 25 In one form, the connection formation comprises a series of spaced fasteners for fixing to each end of a wall element, each said fastener having a shaft portion and an enlarged head portion. In this form, the wall elements suitably comprise a plurality of wall boards. 30 In an alternative form, the connection formation comprises a connection profile, suitably of substantially "T" shaped cross-section. In the alternative form, the wall 6 elements suitably comprise wall panels preferably including external cladding and internal lining. In yet another aspect there is provided a method for constructing a wall for a building, 5 said method including the steps of: providing a plurality of elongate structural members, each member including at least one longitudinal channel in a first section of a respective member, said longitudinal channels each having a continuous mouth defined by opposed flanges forming a face in the first section of respective elongate structural members; 10 anchoring at least first and second elongate structural members of said plurality in an upright spaced relation, whereby said faces of the upright elongate structural members are opposite one another; providing a wall panel adapted to span the space between said first and second elongate structural members; 15 fixing a connection profile to first and second ends of said wall panel, each profile having an exposed tail portion and a head portion; sliding the head portions of the respective first and second connection profiles downwardly into open ends of the respective first and second channels of the spaced elongate structural members, wherein the head portion of each connection profile is 20 retained in the longitudinal channel such that the associated exposed tail portion protrudes between said opposed flanges and outwardly through said mouth; and whereby the wall panel is secured at each end adjacent to respective faces of first sections of the first and second elongate structural members in order to span the upright elongate structural members. 25 In still another aspect of the invention, there is provided a method for constructing a wall for a building, said method including the steps of: providing a plurality of elongate structural members, each elongate member including at least one longitudinal channel in a first section of a respective member, 30 said longitudinal channels each having a continuous mouth defined by opposed flanges forming a face of respective elongate members; 7 anchoring at least first and second elongate structural members of said plurality in an upright spaced relation, whereby said first faces of the upright elongate structural members are opposite one another; providing a plurality of wall boards adapted to span the space between said 5 first and second elongate structural members; fixing a series of spaced fasteners to first and second ends of said plurality of wall boards, each fastener having an exposed shaft portion and an enlarged head portion; sliding the enlarged head portions of the respective first and second series of 10 fasteners downwardly into open ends of the respective first and second channels of the spaced elongate structural members, wherein the enlarged head portion of each fastener is retained in the longitudinal channel such that the associated exposed shaft portion protrudes between said opposed flanges outwardly through said mouth; and 15 whereby the plurality of wall boards are secured at their ends adjacent to respective faces of the first sections of the first and second elongate structural members in order to span the upright elongate structural members. In the specification the term "comprising" shall be understood to have a broad 20 meaning similar to the term "including" and will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the term "comprising" such as "comprise" and "comprises". 25 BRIEF DETAILS OF THE DRAWINGS In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate preferred embodiments of the invention, and wherein: FIG. 1 is an exploded and fragmented perspective view of a portion of a wall 30 construction illustrating a first embodiment of a connection arrangement for a wall construction; FIG. 1A is an enlarged side elevational view of part of a wall board comprising the wall construction of FIG. 1; 8 FIG. 1B is a cross-sectional view of an elongate structural member comprising the wall construction of FIG. 1; FIG. 2 is a fragmented perspective view of a wall and window fixture of a building construction utilizing the connection arrangement of FIGs 1, 1A and 1B; 5 FIG. 2A is a cross-sectional view of a further elongate structural member for use with the window fixture of FIG. 2; FIG. 3 is a fragmented perspective view of a wall and window fixture of a building construction utilizing a variant of the further elongate structural member having an integral jamb section; 10 FIG. 4 is an exploded and fragmented perspective view of a portion of a wall construction illustrating a second embodiment of a connection arrangement for panel type wall construction; FIG. 5 is an exploded and fragmented perspective view of a further portion of the panel type wall construction of FIG. 4, illustrating a third embodiment of a 15 connection arrangement; FIG 5A is a cross-sectional view of an elongate structural member comprising the wall construction of FIG 5; FIG. 6 is a cross-sectional view of another elongate structural member for a further embodiment of the connection arrangement of the invention; and 20 FIG. 7 is a perspective view of a building including the panel type wall construction shown in the fragmentary views of FIGs 4 and 5. DESCRIPTION OF EMBODIMENTS OF THE INVENTION An elongate structural member in the form of a corner post 100, here a hollow 25 extrusion composed from aluminium preferably of grade 6106 T6, is shown in FIGs 1 and in cross-section in FIG. 1B. The corner post includes two integral sections 110, 120 arranged generally perpendicular to one another. Each section of the post has a compound channel 112, 122 for interconnection with a wall element, such as wall board 150. The compound channels will be conveniently described in relation to the 30 channel 112 in the first section 110, the channel 122 in the second section 120 having a similar configuration.
9 The compound channel 112 includes an inner channel 114 and an outer channel 116. The compound channel 112 has an outwardly disposed face 118 intermediate the inner and outer channels, which face is formed by edge-wise opposed flanges 118a, 118b. The opposed flanges also define a continuous mouth 119 5 therebetween, which mouth takes the form of a longitudinal slot in this embodiment. The inner channel 114 is further defined by an inner channel wall 115 (see FIG. 1B) which bridges the opposed flanges inwardly of the mouth 119. The inner channel 114 communicates with the outer channel 116 via the mouth 119. 10 The outer channel is defined by the outwardly disposed face 118 and facing wall portions 117a, 117b of the first section 110, which facing wall portions are integral with outermost walls 102, 104 of the corner post 100. The post 100 further includes an internal void 106 (see FIG. 1B) between the first and second sections 110, 120; which internal void may be conveniently used for carrying conduits, cables or the like 15 for utility services such as electricity, gas, water and data services. Stiffening ribs 113, 123 are also provided in the first and second sections 110, 120 for added structural integrity of the corner post 100. The wall board 150 of FIG 1 includes double tongue 152 and cooperating double 20 groove 154 formations on opposite lateral edges thereof. The tongue and groove formations 152, 154 are configured for interlocking lateral stacking of adjacent wall boards, as illustrated in FIG. 2. It will be appreciated that such "V-J" type wall boards can include multiple tongues and grooves, for example a 70mm wide board may have up to 4 tongues for lateral strength. At least one mechanical fastener, here in 25 the form of a hexagonal head screw fastener 160, preferably of #14 gauge, is fixed into an end face 156 of wall board 150. As shown in the enlarged view of FIG. 1A, the fastener 160 includes an enlarged head portion, in the form of a hexagonal head 162 with a peripheral flange 164, and a 30 screw-threaded tail portion 168 for securely fixing into the timber body 158 of the wall board 150. The screw fastener 160 is fixed at a predetermined depth in the timber body, such that there is provided an exposed shaft portion 166 of the fastener 10 between the peripheral flange 164 of the head portion and the end face 156 of the wall board 150. During construction of a wall, wherein the elongate structural member or post 100 is 5 anchored in an upright orientation and an open end of both the inner channel 114 and the outer channel 116 in the first channel section 110 is exposed, the enlarged head portion of fastener 160 is aligned with the inner channel 114 and the body of the wall board 150 aligned with the outer channel 116. The wall board is then lowered such that the head portion slides downwardly into the inner channel, and the 10 exposed shaft portion 166 of the fastener 160 passes along the continuous mouth 119 defined by the edge-wise opposed flanges 11 8a, 11 8b of the corner post 100. Outer longitudinal faces 157 of the wall board are coincidentally received by inner surfaces of the outer flanges 11 7a, 11 7b of the post, and the first face 118 formed by 15 the opposed flanges 118a, 118b guides the end face 156 of the wall board 150. The continuous mouth 119 is dimensioned such that the enlarged head portion cannot pass laterally between the opposed flanges 118a, 118b, thereby effectively securing the wall board 150 in position laterally, whilst allowing it to slide downwardly. 20 In FIG. 2 there is shown a portion of a wall 200 assembled using the corner post 100 as described above and another example of an elongate structural member in the form of a terminating profile 130 for use with a window or door jamb, here a timber window jamb 140. The post 100 is anchored in an upright position in spaced relation with the profile 130 which in turn is fixed to the window jamb by screws 142. Sealant 25 may also be applied and, in alternative embodiments the screws may be augmented, or in some variants replaced, by an adhesive. The window jamb 140 is provided for a metal framed window assembly 145 which includes a metal frame 147 and a glass pane 149. 30 The terminating profile 130 includes a first section 131 having a configuration equivalent to the first (and second) sections of the corner post 100, as will be appreciated by reference to the cross-sectional view of the profile in FIG. 2A. The first section 131 includes a compound channel 132 having an inner channel 134 and 11 an outer channel 136. The compound channel 132 has an outwardly disposed face 138 intermediate the inner and outer channels, which outward face is formed by edge-wise opposed flanges 138a, 138b. The opposed flanges also define a continuous mouth 139 therebetween, which mouth takes the form of a longitudinal 5 slot, similarly to the corner post above. The inner channel 134 is further defined by a continuous inner channel wall 135 which bridges the opposed flanges 138a, 138b inwardly of the mouth 139. The inner channel 134 of termination profile 130 communicates with the outer 10 channel 136 via the mouth 139. The outer channel is defined by the outwardly disposed face 138 and facing wall portions 137a, 137b of the section 131, which wall portions are integral with outermost walls of the profile 130. The outermost walls of the first section 131 terminate in stiffening ribs 133, which also provide a larger surface area facilitating the application of a flowable sealant. Apertures (not shown) 15 are provided at spaced intervals in the opposed flanges of the intermediate face 138 for retaining means such as screws 142 (see FIG 2). A plurality of wall boards 150, as described above, that are pre-sized for spanning the space between the upstanding post 100 and profile 130 are lowered downwardly 20 into position, as shown in FIG 2. The wall boards 150 are secured laterally by way of fasteners 160 pre-fixed in each end surface of the respective boards, the enlarged heads 162 of which fasteners slide in the inner channels 114 and 134 of the first sections of the post 100 and terminating profile 130, respectively. It will be appreciated that the series of fasteners 160 fixed to end surfaces 156 of the wall 25 boards effectively constitute a connection formation and, depending on the width of the boards, the boards may each include two or more fasteners 160 in each end surface 156. End portions of the wall boards 150 suitably nest snugly in the outer channels 116, 30 136 of the respective first sections 110, 131 for positive location of the wall boards in the connection arrangement of the present embodiment. Upright cyclone rods 202 may also be utilised to vertically tie a stack of wall boards 150, where demanded by applicable building regulations or as specified by the owner. Suitably an aperture for 12 receiving the cyclone rod is provided in the body of the wall boards between the double tongues 152. A further example of an elongate structural member is shown in relation to a wall 5 portion 250, as illustrated in FIG 3. The further example is a combination jamb and wall locking profile 170, which combines the structural features of the terminating profile 130 in a first section 171, and the structural features of the jamb 140 (whether for a window, door or other opening) in a second section 180, combined in a single hollow aluminium extrusion which provides a void 186 for services. 10 The first section 171 includes a compound channel 172 having an inner channel 174 for receiving enlarged heads of a series of spaced fasteners (not visible), and an outer channel 176 in which end portions of the wall boards 150 may nest. Edge-wise opposing flanges 177a, 177b define a mouth in the form of a continuous slot 179 15 between inner and outer channels 174, 176. The face 177 provided by outer surfaces of the opposing flanges is abutted by end faces 156 of the wall boards 150. The second section 180 of the combination profile 170 also has provision for a snap on window frame profile 187, which profile here supports a glass pane comprising 20 window 189. Alternative snap-on profile members of different configurations may be provided for doors of various kinds, including entry and garage type doors. Turning to FIG 4, there is illustrated a connection arrangement 300 of a second embodiment of the present invention. The elongate structural member of this 25 embodiment again happens to take the form of a corner post 100, and accordingly description of its structural features is not repeated here. Alternative elongate structural members for different applications are further described in relation to FIGs 5, 5A and 6, and it will be appreciated that these may be utilised, where required. 30 However, the connection formation of this second embodiment includes a connection profile 310, which has a substantially T-shaped cross-section and is suitably composed of extruded aluminium. For ease of reference an outer portion 312 of the T section is termed its "head" whilst an inner portion 314 of the T section is termed its 13 "tail." The connection profile 310 here illustrated is also integral with an arrangement, formed by a rod member 316 to which wall elements may be fixed. The wall element shown in relation to this second embodiment is a composite wall 5 panel 350 which includes external cladding 352 arranged in close face-to-face spaced relation to internal lining 354. The external cladding and internal lining may be spaced apart by an internal core 358 that may comprise stiffeners, sound or thermal insulation, and/or an expanded plastics or foam core, as required. 10 The integral rod member 316 of the connection profile 310 is tubular and has a square or at least rectangular cross-section which provides an obverse surface 318 and a reverse surface 320 to which surfaces are fixed the external cladding 352 and the internal lining 354 respectively - such as by the screws 322 (visible in relation to the external cladding). End faces 356 of the cladding and lining are suitably coplanar 15 with a face of the fixing rod member 316. When interconnecting the wall panel 350 to the post 100, the connection profile 310 that is fixed adjacent one end of the wall panel is inserted into an open end of the compound channel 112 of the first section 110. During insertion, the head portion 20 312 of the T-shaped profile slides or travels downwardly into the inner channel 114 whilst the tail portion 314 protrudes between the edge-wise opposed flanges 118a, 118b that define a continuous longitudinal mouth 119. The continuous mouth allows communication between the inner channel 114 and the outer channel 116, which outer channel receives one end of the wall panel 300 to which the connection profile 25 310 is fixed. It will be noted that, in the present embodiment, the screws 322 fixing the outer cladding 352 to the connection profile 310 will be concealed behind flange 117b when the end of the wall panel 300 is nested in the outer channel 116 upon assembly of a wall. 30 Depending on the inherent strength of the wall panel, it may extend for the desired full height of the building (as required) or, as depicted in FIG. 7, be one of a matrix of smaller panels 350 secured with the aid of intermediate lateral members 450 which also aid in stiffening upright elongate members (in a manner somewhat similar to 14 noggings). It will be appreciated that alternative embodiments of the composite panel 350 member may include single wall (see FIG. 5), double wall and filled, reinforced or hollow core construction. The lateral members are also of assistance in supporting window frames 185, especially window ledges 188, as also depicted in 5 FIG 7. A third embodiment of an elongate structural member of the invention, which takes the form of an intermediate post 410 for supporting coplanar portions of a wall of building 500, is shown in more detail in FIGs 5 and 5A. The intermediate post 410 includes two sections having oppositely directed 10 compound channels 412, 422. Each section includes an inner channel 414, 424 and an outer channel 416, 426 separated by edge-wise opposing pairs of flanges 418a, 418b and 428a, 428b. As with previous embodiments of elongate structural members, the pairs of opposing flanges define respective continuous mouths 419, 429 which communicate between inner and outer channels of respective sections. 15 The outer channels are further defined in the embodiment by facing pairs of flanges 417a, 417b and 427a, 427b whose inner surfaces abut outer faces of major surfaces 353 of the composite wall panel 350. The end faces 356 of the composite panel 350 are engageable with respective outward faces 418, 428 formed by pairs of opposed flanges 418a, 418b and 428a, 428b. 20 The intermediate lateral members 450, suitably of an extruded aluminium construction, are substantially H shaped cross-section including two facing strips 452, 454 bridged by a central web 456. The facing strips are suitably dimensioned to be snugly received within the outer channels 416, 426 of the intermediate post 410 or 25 other elongate structural member and, in turn, to receive end portions of the wall panels 350, as depicted in FIG 5. The lateral member 450 includes at each end thereof a fastener 460 having a hexagonal head 462 with an enlarged flange 464 and a tail portion 468. Each fastener is fixed to the central web 456, such that an exposed shaft portion 466 is provided between the underside of the head 462 and a 30 leading edge of the central web 456. The head 462 of fastener 460 is arranged to slide downwardly into the inner channel 414, 424 of the intermediate post 410, whereby the exposed shaft portion 466 15 protrudes between opposed flanges 418a, 418b or 428a, 428b and through continuous mouth 419, 429. In this way the ends of the intermediate lateral members 450 can be secured between spaced upright elongate members, such as between corner post 100 and the intermediate post 410, or between the intermediate post and 5 combined jamb/wall locking profile 170. Weep holes 458 are provided in flange 454 to enable any excess liquid that may enter the channel to escape. In FIG 6 there is shown a cross-sectional view of still further embodiment of an elongate structural member which takes the form of a T junction post 600. The T 10 junction post includes three (3) sections, wherein first and second sections 610, 620 have respective compound channels 612, 622 that are generally normal to one another, whilst a third section 630 includes a compound channel 632 which is generally normal to second (central) compound channel 622. The T junction post is most suitable employed for major structural dividing walls. It will be appreciated that 15 alternative constructions may use a further elongate structural member, such as illustrated in FIG 2A, fastened directly to an interior surface of a wall in order to erect internal partitions. In FIG 7 there is shown a portion of a building construction 500 which brings together 20 the connection arrangements and elongate members illustrated earlier by way of example. The building has concrete footings 502 protected from weather by flashing 504, in which footings are anchored a corner post 100, an intermediate post 410 and a window jamb and wall locking profile 170. Intermediate lateral members 450 are further provided for securing an array of composite wall panels 350 and will assist in 25 supporting a window 185. Where additional weather sealing is desired, a self adhesive weather strip or bead of sealant compound, perhaps only a few mm in thickness, could be added to the inner surfaces of either or both outer flanges in order to be sandwiched between the flange and any wall panel or board inserted into an outer channel. 30 One or more embodiments of the wall connection arrangement and method of the invention are capable of delivering practical benefits, including one or more of the following: 16 1. speedier manufacturing techniques and methods, and less equipment required thus reducing costs; 2. less chance of damaging square cut wall boards when compared with the conventional half-check boards usually employed, since checking can 5 affect the natural grain of the timber and cause cracking including both during manufacture, transport, assembly and later in service; 3. the improved strength of building joins which use positively retained fasteners or profiled strips; 4. the ability for hollow extruded posts to house utility services, such as 10 electrical cables; and 5. the general ease of construction by end users, the drop-in locking system for corners, windows and doors can save time, require less tools and reduced natural ability for a novice to assemble. 15 It is to be understood that the above embodiments have been provided only by way of exemplification of this invention, and that further modifications and improvements thereto, as would be apparent to persons skilled in the relevant art, are deemed to fall within the broad scope and ambit of the present invention described herein and defined in the following claims. 20