GB2244501A - Relocatable building system and cladding panel - Google Patents

Abstract

A relocatable building is constructed from prefabricated modules (10) comprising a framework, preferably made from horizontal and vertical box-section steel beams (30). Cladding panels (60) are secured to the outside of the modules to form the outer walls. The cladding panels comprise trays of steel or plastics material having peripheral flanges 85 and projections 70 on their outer surfaces to retain the cladding, e.g. bricks or weather boarding. The modules are preferably supported on a network of concrete beams (14) supported on brick or concrete footings. The modules are preferably made up complete at the factory to include doors, windows, internal wall, floor and ceiling coverings, sanitary fittings and fittings for the supply of utilities. The projections 70 may be wooden strips to which weather boarding is secured. <IMAGE>

Description

RELOCATABLE BUILDING SYSTEM AND CLADDING PANEL USED THEREIN This invention relates to relocatable buildings, and more particularly to buildings of the type constructed from modular units and to cladding panels for use in forming exterior surfaces thereof.

There is an increasing need for semi-mobile and relocatable buildings, for example for the provision of schools. Education authorities often find that there is an immediate need for larger accommodation at one school site whereas some accommodation on another site may have become redundant. There is therefore a need for a flexible relocatable building system to enable accommodation units to be moved from one site to another with a high level of material recovery but providing accommodation of superior quality to that afforded by temporary buildings of the type commonly found for example at construction sites.

GB-A-1470161 discloses a prefabricated building unit comprising a box like structure with a rigid framework constructed from intersecting extruded metal members, a wire mesh being attached to the outside of the framework and a coating of concrete being spread over the wire mesh to the desired thickness to form a covering of ferroconcrete,and a plaster skim being applied to the walls and ceiling in the interior of the unit. The unit is provided with openings as required for doors and windows and the unit can be used to provide for example an extension to an existing building, an outbuilding, a site hut or a holiday home.

The present invention aims to improve the provision of such units by using detachable and reusable wall panels to be secured as required around the exterior of a box-like framework to form a relocatable building module.

According to one aspect of the invention there is provided an exterior wall panel for a relocatable building, comprising a substantially flat tray, suitably of metal, timber or plastics material, with flanges along its peripheral edges to retain a cladding material therein, the flanges preferably being substantially at right-angles to the plane of the tray, projections di-stributed across the surface of the tray, on the same side thereof as the peripheral flanges, to act as ties for the cladding material, and means for securing the tray to a frame of a relocatable building.

The cladding material may for example comprise rendered bricks, brickslips or weatherboarding of wood or plastics material.

According to a further aspect of the invention there is provided a relocatable building module comprising a box-like frame made from elongate beams, which are preferably of extruded metal but could for example be of wood, and a plurality of detachable and reusable panels secured to the outside of the frame to form the walls of the module. The module may suitably have its own floor and/or ceiling structures, or may be integrated into a building wherein these structures are otherwise provided.

By means of the invention a relocatable building may be constructed from a plurality of such building modules in any desired configuration, and the modules can subsequently be relocated and assembled in a different configuration of wall panels to suit the particular requirements of the building being assembled on the new site.

A building may suitably be constructed on foundations formed by steel stools or a network of reinforced concrete beams resting on brick or concrete footings. A roof structure may also be made up of reusable modules, preferably using a box-section steel frame with metal or timber rafters and purlins.

Preferred embodiments of the invention will now be described with reference to the accompanying drawings wherein; Figure 1 shows schematically a relocatable building constructed from modules provided with exterior cladding panels in accordance with the present invention; Figure 2 is a schematic plan view of the layout of the foundations for a building in accordance with the invention; Figure 3 is an exploded view showing how the foundations, a rectangular box-section module, a roof module and exterior wall panels fit together in the construction of a building in accordance with the invention; Figures 4 & 5 show foundation caps used to accommodate the ends of the foundation beams.

Figure 6 is a schematic view of some cladding panels in accordance with the invention; Figure 7 is a side elevation of the outer surface of a cladding panel in accordance with the invention; Figures 8a and 8b are respectively a side view and a rear view of a cladding panel in accordance with the invention; Figure 9 is an elevational view of part of a completed building constructed using the cladding panels of the invention; Figure 10 is an enlarged detailed section on the line X-X in Figure 9; Figure 11 is an enlarged cross-sectional view on the line XI-XI in Figure 9; Figure 12 is an enlarged cross-sectional view on the line XII-XII in Figure 9; Figure 13 is a cross-sectional view showing the junction of two modules within the building, at floor level; Figure 14 is a cross-section on the line XIV-XIV in Figure 9.

Figure 15 is a partial section on the line XV-XV in Figure 9; Figure 16 is a cross-section on the line XVI-XVI in Figure 9; Figure 17 is a cross-sectional view through one side of a building showing the relationship between the foundations, the basic modules and the roof structure; Figure 18 is a schematic perspective view showing how a roof module fits onto the box structure of a building module in accordance with the invention; Figures 19 and 20 show steel stools which may be used as supports for a building in accordance with another embodiment of the invention; Figure 21 shows the inner sides of cladding panels in accordance with a further embodiment of the invention, with cross-sectional views of strengthening and attachment members;; Figure 22 is a vertical cross-section similar to those of Figures 10 and 11, illustrating a further embodiment of the invention using the panels of Figure 21; Figure 23 is a horizontal cross-section similar to that of Figure 12, illustrating further aspects of the embodiment of Figure 22; Figure 24 is a horizontal section through a corner of the building of Figures 22 and 23; and Figure 25 is a detail of the attachment of the panels of Figure 21.

Referring first to Figure 1, this shows schematically a building constructed from a plurality of relocatable modules, including rectangular modules 10, which between them make up the accommodation space, and roof modules 12. The rectangular modules 10 comprise box section steel frameworks which will be described in more detail below. These frameworks are connected together and are provided with floors, ceilings, internal and external walls as required. The external walls are formed by cladding panels such as 60 which are bolted on and which can accommodate doors and windows such as 16.

The roof modules 12 also comprise box-section steel frameworks which may support conventional roof timbers.

In the building shown, the rectangular modules surround a central open area which is topped by a square roof unit which may suitably comprise transparent panels.

The rectangular modules are supported on a foundation grid 14, which is shown in more detail in Figure 2. The foundation grid is made up of preformed steel or reinforced concrete beams 20 which extend between concrete or brick footings 22 on which they are supported.

The ends of the beams interlock with foundation caps 24, 25 which are bolted to the tops of the concrete footings 22.

Figure 3 shows in more detail a rectangular module 10 which is constructed from horizontal and vertical boxsection steel beams 30. These form a rectangular base section 31 on which extend six vertical beams 38 which support a rectangular upper section 33. These upper and lower sections support transverse floor and ceiling joists 32 on which conventional floors and ceilings can be formed.

Figure 3 also shows in more detail the foundation beams 20 and the foundation caps 24, 25 in which they engage.

The building shown in Figure 3 is a single-storey building in which rectangular accommodation modules 10 support roof modules 12 immediately above them. It will be appreciated however that rectangular accommodation modules could also be stacked one above the other to form a twostorey or multi-storey building.

The roof module 12 is also constructed from boxsection steel beams 34, and is shaped to form a pitched roof. It will be appreciated that flat roofs may also be constructed with the system of the invention. The steel framework supports purlins 35 and rafters 36, which may comprise conventional timber beams. The framework has a base of the same area as the rectangular module which supports it, so that beams are positioned directly above one another and can be bolted together.

The external walls of the building are formed by cladding panels 60 which are bolted to the vertical columns 38. These panels will be described in more detail below.

Figure 4 shows in detail a foundation cap 24, suitably made of galvanised steel. This comprises a base plate 40 with bolt holes 41 to secure it to the top surface of a concrete footing. Welded to the upper side of the base plate are vertical plates shaped to engage with the ends of foundation beams. These comprise a central wall 45 and a pair of end walls 42 at right-angles thereto, forming an H-shaped section into which the adjacent ends of two longitudinally aligned beams engage.

Extending from the ends of the end walls 42 are four vertical flanges 44, parallel to the central wall 45, defining two further bays which can receive respective ends of two further longitudinal aligned beams, at right-angles to the two first mentioned.

Figure 5 shows another form of foundation cap, accommodating the ends of the beams at the corners of the building, as shown in Figure 3. Like the foundation cap 24, this can be made from galvanised steel and comprises a base plate 50 which in this case is square. Welded to the base plate are vertical steel walls defining a central square with flanges 54 extending from its corners to define four bays 55 to receive the beam ends.

Figure 6 shows in more detail the cladding panels 60 which comprise steel trays with outwardly extending peripheral flanges to accommodate the cladding material such as brick slips or weatherboarding. These trays are generally of rectangular shape, and their length may suitably correspond to the width of the steel framework of one of the rectangular building modules 10, which preferably also corresponds to half the length of one of these modules, so that the panels can be secured at their ends to two columns 38 at respective corners of the module, or between one corner and a column 38 halfway along the length of the module. The lowermost panels can also be secured to the base beams of the module and the uppermost panels to the top beams. The height of the panels suitably comprises one half or one third of the height of a rectangular module.

On the inner sides of the panels, i.e. on the opposite side to that which accommodates the cladding, there are provided means for securing the panels to the module frame. These may suitably be in the form of steel angle members 62, welded to the rear of the panel and shown in dotted lines in Figure 6. Also shown in dotted lines are horizontal steel plate stiffeners 64 and vertical stiffeners 36, intersecting in a grid pattern so as greatly to increase the rigidity of the panel.

Figure 7 shows a typical arrangement of brick ties 70 on the outwardly facing surface of a tray used to form a cladding panel 60. The ties 70 may suitably be in the form of metal angle pieces welded to the surface of the tray.

Other types of support may be provided, depending on the particular form of cladding material to be accommodated in the tray.

Figures 8a and 8b are respectively an edge elevation and a rear view of a shorter panel, for use for example where a door or window is to be incorporated into the side of the module. This again comprises a steel tray having a peripheral flange 85 around its edge on its outwardly facing side to accommodate cladding material. On the rear side shown in Figure 8b, horizontal steel plate stiffeners 64 are provided, as in the panel of Figure 6.

Adjacent the lower edge a steel angle member 82 is welded to the tray, for use in securing it to a beam of a module frame, and vertical angle members 84 are provided adjacent the opposite side edges of the tray for securing it to the vertical columns of a module frame or for connection to a door or window frame.

The building in Figure 9 is a single-storey building typical of what can be constructed using the system of the invention. The section shown in Figure 9 is the length of two rectangular modules, corresponding to the length of four cladding panels arranged end to end. The cladding panels include three which have a brick cladding 90 and others provided with weatherboarding 92. Windows 93, which may be of conventional design, are incorporated in some of the modules and a roof 96, constructed of modules such as those shown in Figure 3, is supported on the rectangular accommodation modules. The roof modules support conventional guttering 95.

Figure 10 shows a cross-section of part of the foundations and floor as well as the lower part of a wall of the building shown in Figure 9. The outer part of the wall is formed by a cladding tray 60 as disclosed in Figures 6 - 8 and containing a cladding of brick slips 90 supported by the flange 85 and brick ties 70 which comprise angle members welded to the outer surface of the tray 60.

The brick slips are also held by a cement filling 101.

On the rear side of the tray 60 is a steel angle member 62 welded to the tray and secured to a square section beam 31 forming part of the base of an accommodation module as described above. The angle member is secured to the beam by means of a bolt 102. The beam may be filled with injected insulating material.

The beam 31 rests on a concrete beam 20 which forms part of the foundations. The beam 20 is topped by a dampproof course 100 and a further damp-proof membrane 103 extends from the upper side of the beam 31 around its outer and lower sides, between the beam and the damp-proof course 100, and under the floor so as to provide comprehensive damp-proofing for the floor.

Floor joists 32 are supported at their ends on brackets 104 which in turn are supported by the beam 31.

Under the floor joists and above the damp-proof membrane 103 is a marine ply lining 105 which may be factoryfitted to the module before delivery to the site. The joists support a floor 106, suitably made from flooring grade chipboard.

The wall is lined with an insulating material 107, having an outer damp-proofing layer 110. On the inner side of the wall is a layer of plasterboard or the like 108. A removable skirting board 109 gives access to the bolt 102 securing the outer wall panel.

Figure 11 shows a section through a lower part of a window frame and an upper part of a wall section supporting the window frame. The wall section again comprises a cladding tray 60 provided with horizontal stiffeners 64 and peripheral flanges 85. In this case the cladding is in the form of interlocking strips of plastics weatherboarding 111 secured to timber battens 112 by means of screws such as 124. An internal lining of building paper is provided between the timber battens and the metal tray 60.

The wall is again provided with a layer of insulation 107, located between the outer damp-proofing layer 110 and the inner wall 108 of plasterboard.

At the top of the wall section is a stud 113, preferably of timber, to which the upper edge of the dampproofing membrane 110 is secured. A further damp-proofing layer 123 extends from the top of the stud 113 around the top edge of the tray to the top of the weatherboarding which is held in place by an aluminium cill section 120.

The cill 120 is secured to the lower part of a window frame made up of extruded aluminium sections. These include sections 115 and 116 which are secured to the stud 113 by means of screws 117 and inner frame sections 118 and 119 which interengage with sections 115 and 116. The cill section 120 is screwed to the intermediate frame section 119. The window frame thus formed accommodates a a conventional aluminium double-glazed window 114.

On the inner side of the window is a wooden cill 121, also supported on the stud 113.

Figure 12 is a horizontal cross-section through a junction between two adjacent trays each holding a cladding of brick slips 90. Each of the trays is secured by a vertical angle member 84 and bolt 125 to a vertical column 38 of the frame of a rectangular building module. These columns, like all the box-section components of the module, is preferably filled with an insulating material.

The junction between the two adjacent trays is packed with a suitable waterproof sealant 126 which may be in the form of an extruded strip of mastic or the like or may be applied in situ using for example a liquid polysulphide resin.

As in Figure 11, the wall insulation 107 is retained between a vertical damp-proof membrane 110 and a plasterboard panel 108, the latter being secured in each case to a vertical timber stud 126. The vertical studs 126 are located on each side of the columns 38, a further plasterboard panel 127 extending between them to conceal the columns and give a continuous internal wall.

Figure 13 shows in vertical cross-section the junction at floor level between two adjacent accommodation modules. The adjacent horizontal box-section beams 31 of the two modules are supported on concrete footings 130, with the interpositioning of a damp-proof course 131 overlying the footings and a continuous damp-proof membrane 132 which extends under the whole floor. The beams are connected together by steel plates 134 secured to the beams 31 by bolts 135. As in Figure 10, the beams support timber joists 32 by means of brackets 104, with a marine ply lining 105 underneath and flooring 106 above. An additional flooring section 136 extends above the two beams, this being removable to allow access to the bolts 135. The trimmers 133 extending at right-angles to the joists 32.

Figure 14 is a horizontal cross-section through a junction between respective vertical columns 38 of adjacent accommodation modules 10, supporting windows on each side.

Each of the columns 38 has, on the side facing away from the adjacent column, a strip 143 secured thereto to hold an extruded aluminium window frame section 42 which has a 'U' shaped channel section with projections which snap around corresponding projections 145 on the strip 143. The frame of which the section 142 forms part supports a conventional sealed double-glazing unit 114. Internal cills 121 similar to that shown in Figure 11 are provided on each side of the pair of adjacent columns, and a continuous extruded aluminium cill section 120 extends in front of both windows.

The exposed parts of the columns are concealed by plastic-coated aluminium column caps in the form of continuous strips provided with hook-shaped engaging flanges along each edge to engage corresponding hook-shaped flanges on the vertical window frame sections 142. The internal column caps 141 are similar to the caps 142 except that they have extended side portions, also with hookshaped edges which engage around corresponding hook-shaped flanges 144 on the strips 143. Packing strips 147 are provided between the columns 38 and the inner column cap 141.

Figure 15 shows a partial vertical cross-section through the junction of the roof and the top of one wall, and also showing a lower section of the wall.

The roof module, of which only the eaves section 150 is shown, comprises horizontal box-section beams 34 as described in connection with Figure 3, which are supported on the upper horizontal beams 33 of the accommodation module.

The lower part of the wall shown in this figure is constituted by a wall panel 60 with a brick slip cladding 90 as described above. The upper part of the wall, above horizontal timber stud 113, is formed by weatherboarding 111 which is secured not to cladding trays but to timber battens such as 151 which in turn are secured to the steel frame of the module. Along the bottom edge of the weatherboarding adjoining the upper edge of the cladding tray 60, a strip of metal flashing 152 is provided to allow condensation or any trapped water to drip out from behind the weatherboarding.

Figure 16 is a horizontal cross-section through a junction between adjacent cladding trays, one of which contains a cladding of brick slips 90 and the other of which contains weatherboarding mounted on timber battens 160. The arrangement is similar to that of Figure 12, except that the junction between the two battens is bridged by an extruded plastics strip 162 having on its inner side 2 pair of projections 163 defining a channel within which is engaged a securing strip 161 which engages by friction between the edge flanges 85 of the cladding trays 60 and snap fits into the channel 163. As in the case of Figure 12, the junction may also be filled with a suitable sealant material.

Figure 17 is a vertical section through the whole of one side of a building, including the foundations. This shows a modified foundation which does not use the foundation caps of Figures 4 and 5. Instead, concrete footings 170 are provided with channels 176 intersecting at right-angles to receive reinforced concrete foundation beams 172 and 173. The beams 172 are of rectangular cross-section, similar to those shown for example in Figure 3. Beam 173 has a more complex shape including a shoulder 176 which supports an outer brick skin 174 extending from ground level to the underside of window cill 120.

The building shown in Figure 17 is otherwise constructed in much the same way as that of Figure 3, a rectangular accommodation module supporting a roof module 12. Also shown in this figure is a ceiling 175 formed in a conventional manner using plasterboard or the like supported by ceiling joists 178 with a layer of insulating material 179.

Figure 18 shows in more detail a roof module 12 and its engagement with an accommodation module 10. It can be seen that the steel beams 34 of the roof frame rests directly on the upper horizontal beams 33 of the accommodation module. At each corner of the roof module is a square projection 180, adapted to be accommodated within the open square section 181 of the corresponding vertical column 38 of the accommodation module.

Figures 19 and 20 illustrate steel stools which may be used in place of the reinforced concrete beams to support the modules of the invention. Each of these stools has a square base 190 with bolt holes 191 by means of which it can be secured to a brick or concrete base. Centrally positioned on the base is a pillar having an H-shaped horizontal cross-section which supports a top plate, the whole assembly being welded together. In Figure 19, the top plate 195 is offset towards one corner and has a single bolt hole 196. The stool shown in Figure 19 is intended to support one corner of a building, one of the base beams of a module being bolted to it. The bolt hole 196 is in the form of an elongate slot to allow for positional adjustment.

The stool of Figure 20 is intended to support a central part of the building, and accordingly its top plate 200 is symmetrically positioned on the pillar 193 and has an elongate bolt hole 206 at each corner.

Figure 21 shows a cladding panel 212 and two panels 210 as positioned on the wall of a building to support and flank a window. The cladding panels are similar in principle to those of Figures 7 and 8, but comprise wooden boards with peripheral steel angle members forming the flanges to surround and support the cladding. Figure 21 shows the inner sides of the panels,-on which are provided vertical strengthening members 214, in the form of steel strips of U-shaped cross-section and, on the longer lower panel 212, diagonal strengthening members 216.

Further U-shaped sections 217 are provided along the upper and lower edges of the panel 212, and similar sections 218 are provided along the upper and lower edges of each of the panels 210.

The side edges of each of the panels are provided with connecting members 213 which are also of U-shaped cross-section (as shown above and below the panels in the drawing), these being provided with support pins 215 which pass through apertures therein and are welded in position.

The function of these pins will be described in more detail below.

Referring to Figure 22, the module shown here has a base formed of steel beams 220 of U-shaped cross-section, which rest directly on steel stools such as 193 and are secured thereto by means of bolts 198. The bolts 198 also hold in position the bottom floor panel 105 which, as in Figure 10, incorporates a damp-proof membrane. A neoprene rubber isolating layer 221 is wrapped around the outer surface of the beam 220.

Supported on the beam 220 is a stud partition section 227 of mild steel to which is secured a steel angle member 231 on which rests an edge of the floor 106. As in figure 10, the floor 106 is supported on joists 32. A layer of insulation may be enclosed between the floor 106 and the bottom floor panel 105.

As in Figure 10, the inner wall is constituted by a panel of plaster board 108 with a skirting board 109.

Above this panel a channel-shaped member 229, supported on wooden battens 224, can be used for example to accommodate a duct for ventilation or electrical cables.

Behind the panel 108 a layer of insulation 107 is enclosed between upper and lower stud partition sections 227. A further stud section 228 is supported above the upper section 227, and an inner window cill 226 is supported on this.

Two further layers of insulation 223 are provided between the layer 107 and the cladding tray 212. A ventilation gap 219 is provided between the cladding tray and the outermost layer of insulation 223. An outer window cill 225 extends above the upper edge of the cladding panel 212.

Figures 23 and 25 show how the cladding panels 212 of this embodiment of the invention are secured to the frame. As in Figure 12, this view shows the adjacent edges of two cladding panels between which is a seal 126, for example a mastic strip. Each of the cladding panels comprises a wooden board 211 with peripheral steel angle members 254 forming the peripheral flanges. Secured to the back of each panel is a connecting member 213, in the form of a U-shaped cross-section steel stud. As can be seen in Figure 23, the adjacent connecting members of the two panels are arranged to face one another so as substantially to enclose a cavity into which a rock wall cavity barrier 224 may be inserted on site.

Each of the connecting members 213 has support pins 215, each projecting outwardly into a slot 255 in a steel support bracket 230. At the bottom of the slot 255 is an alignment notch 256 to assist correct positioning of the support pin 215.

The steel support bracket 230 is adjustably secured to a support flag 232, in the form of a steel flange, by means of two friction bolts 252 which pass through elongate slots 250 to allow adjustment of the position of the support bracket. The opposite edge of the support flag 232 is welded to a vertical box section pillar 38 of the module frame. The two pillars 38 shown in Figure 23 are positioned close to one another, with a sealing layer 225 of mastic or the like between them. A further sealing layer 225 is provided between adjacent edges of the insulating panels 223.

Referring finally to Figure 24, this shows how a further cladding section 240 can be used to enclose a corner of the building. The section 240 has a central stiffening member 246, again in the form of a U-shaped steel stud section, and a pair of U-shaped connecting members 244 secured to its respective vertical edges. The sections 244 are provided with support pins 245, similar to the pins 215 shown in Figures 23 and 25. These engage in corresponding apertures in sections 243 which fit within the connecting members 213 of adjacent cladding panels 212.

These panels are in turn secured, as shown in Figures 23 and 25, to support brackets 230 which are in turn secured, in the same way as described in relation to Figure 25, to support flags 241 which are welded to adjacent sides of a vertical pillar 38 of the module frame and extend at right angles relative to one another.

The accommodation modules 10 are preferably factory built as far as possible, being equipped with doors, windows, floor, ceiling and wall coverings, damp-proof membrane and internal fittings such as electrical wiring, water supply and sanitary fittings before being taken to the site so that only a minimal amount of assembly is necessary on site once the foundations have been laid. If it is desired to relocate all or part of the building, the individual modules can simply be unbolted and transported to the new site, their cladding panels being replaced or repositioned as necessary.

Claims (18)

CLAIMS:

1. An exterior wall panel for a relocatable building, comprising a substantially flat tray with flanges extending from one side thereof along its peripheral edges to retain a cladding material therein, projections distributed across the surface of the tray, on the same side thereof as the peripheral flanges, to act as ties for the cladding material, and means for securing the tray to a frame of a relocatable building.

2. A wall panel according to claim 1 wherein the tray is made of steel.

3. A wall panel according to claim 1 or claim 2 wherein metal stiffening plates are secured to the side of the tray opposite that from which the cladding ties project.

4. A wall panel according to any preceding claim wherein the means for attachment to the building frame comprise metal angle members secured to the side of the tray opposite to that from which the cladding ties project.

5. A wall panel according to any preceding claim wherein the cladding ties comprise a plurality of metal angle members distributed across the surface of the tray.

6. A wall panel according to claim 5 wherein the cladding is in the form of bricks or brick slips.

7. A wall panel according to any one of claims 1 to 4 wherein the cladding ties are in the form of timber battens.

8. A wall panel according to claim 7 wherein the cladding is in the form of wooden or plastics weather boarding.

9. An exterior wall panel for a relocatable building, substantially as herein described with reference to the accompanying drawings.

10. A relocatable building module comprising a box-like frame made from elongate beams and a plurality of detachable and re-usable panels secured to the outside of the frame to form the walls of the module.

11. A module according to claim 10 wherein the elongate beams are made of box-section steel.

12. A module according to claim 10 or claim 11 wherein the box-like frame includes a base section supporting a plurality of floor joists and/or an upper section supporting a plurality of ceiling joists.

13. A module according to any one of claims 10 to 12 having a damp-proof membrane secured to its underside.

14. A module as claimed in any one of claims 10 to 13 wherein the frame comprises upper and lower portions of substantially identical rectangular shape, the upper portion being supported above the lower portion by vertical columns.

15. A module according to any one of claims 10 to 14 wherein the wall panels are secured to the outer sides of the beams to which they are secured, and conceal those beams.

16. A module according to claim 15 wherein an inner wall structure is provided, inner wall panels being supported by the beams on the inner sides thereof and insulating material being held between the inner and outer wall panels.

17. A relocatable building module substantially as herein described with reference to the accompanying drawings.

18. A relocatable building constructed from a plurality of modules according to any one of claims 10 to 17.