NZ707749A - Interlocking Blocks and Tiles for Buildings - Google Patents

Abstract

Disclosed is a mutually interlockable set of components for use in building construction with tongue and groove edges that are moulded in a single step to provide efficient manufacturing of the components. The or each member of the set is a single, moulded component having a width and a height and a thickness; all members of the set having compatible physical dimensions and having interlocking joint formations selected from a range of a tongue and a groove. Each member being completely encased within an outer skin extended over both outer surfaces; the outer skin comprising all surfaces of the joints and comprised of one or more first solid-setting fused thermoplastics materials. The skin encloses an attenuated interior volume comprised of a second foam-setting fused thermoplastics material; the joint formation comprised of either a tongue or a groove being located along a side of a perimeter. The tongue formation includes the second foam-setting fused thermoplastics material passing into an interior of the tongue. Each member of the set thereby being capable, when moulded, of forming interlocking joints with other members of the set. Each member of the set is moulded into the shape of a triangular prism and is capable of being interlocked with other members of the same set by means of moulded interlocking joints around three sides of the perimeter of each member; the joints being capable of being secured by at least one of an adhesive fastening means and a physical fastening means. thickness; all members of the set having compatible physical dimensions and having interlocking joint formations selected from a range of a tongue and a groove. Each member being completely encased within an outer skin extended over both outer surfaces; the outer skin comprising all surfaces of the joints and comprised of one or more first solid-setting fused thermoplastics materials. The skin encloses an attenuated interior volume comprised of a second foam-setting fused thermoplastics material; the joint formation comprised of either a tongue or a groove being located along a side of a perimeter. The tongue formation includes the second foam-setting fused thermoplastics material passing into an interior of the tongue. Each member of the set thereby being capable, when moulded, of forming interlocking joints with other members of the set. Each member of the set is moulded into the shape of a triangular prism and is capable of being interlocked with other members of the same set by means of moulded interlocking joints around three sides of the perimeter of each member; the joints being capable of being secured by at least one of an adhesive fastening means and a physical fastening means.

Description

TITLE: INTERLOCKING BLOCKS AND TILES FOR BUILDINGS.

FIELD: The invention relates to blocks and tiles that can interlock and be used to construct buildings; and in particular the invention relates to interlocking blocks and tiles formed from a plastics material by a rotational moulding process.

DEFINITIONS The outer surface of any one block or tile is herein called “a skin”.

The skin encloses an “interior volume”.

The visible exterior surface of a wall is herein called the “external surface” The invention refers to any one compatible article belonging to the limited range or set of components as being a member of the set.

BACKGROUND The inventor has previously described buildings, such as dwellings, made from a plastics material by a rotational moulding process in a large oven holding a heated mould that is rotated in one axis only, while feeding a flow of a selected type of plastics granule (to set solid or to set as a foam) into the interior of the mould. Such an oven can produce a round building several metres in diameter and several metres off the ground, as a single item.

The inventor has previously described unitary parts for buildings made of fused plastics by rotational moulding techniques but the shapes of the parts were generally dictated by the shape of the rotating oven and retained curved or circular forms, rather than by following the usual building conventions that seek rectangular or cubic modules, like bricks, for assembling rectangular buildings of unlimited size. For example, in WO/2008/133535 the Applicant described “a bell-shaped product capable of conversion into a dwelling is made in this manner inside a metal mould, open at one end and slowly rotating about a horizontal axis in an oven”. That is a 2 metre diameter oven.

The prior-art finished structures retained dimensional limits of the rotating ovens. In WO2010/036130 the present Applicant described a single-axis rotational moulding apparatus which conveniently forms planar or curved three-dimensional shapes of plastics, suitable as modules for buildings. An erectable, demountable building made of such modules may be shipped in the disassembled state and then erected by untrained personnel on a site. The modules may be made of wood or plastics. Preferred modules are made by rotational moulding and include insulation-filled cavities serving as thermal insulation. A further oven is used to fabricate large cylinders. After removal the hot cylinders are flattened into sheets of plastics material for use as flooring.

In the prior art, moulded plastic blocks are known –such as US 5904019 to Kooij and US 5933245 to Kline. These blocks are made by injection moulding and each comprises two parts with a base and sides that are joined together in order to make a hollow block containing air. The preferred material is a transparent plastics material, such as polycarbonate, in order to emulate glass bricks. The joints around the edges are not 40 strong and do not include any thermally insulative material.

PROBLEM TO BE SOLVED: Rotational moulding ovens have limited dimensions, smaller than many buildings. In order to overcome this problem, the invention aims to provide modular blocks conforming to a set of standard dimensions, using the inventor’s prior-art process. These allow 45 structures, such as buildings, to be constructed in the same way that bricks or concrete blocks can be assembled.

OBJECT An object of the present application is to provide a set of components for constructing a building at a site, or at least to provide the public with a useful choice. 50 SUMMARY OF INVENTION In a first broad aspect, the invention provides one or more members of a mutually interlockable set of components for use in building construction, wherein the or each member is a moulded component having a width and a height and a thickness; all members of the set having compatible physical dimensions; each member having an outer 55 skin comprised of one or more first solid-setting fused thermoplastics materials; the skin enclosing an attenuated centre comprised of a second foam-setting fused thermoplastics material; each member of the set including complementary, integral, moulded interlocking joints comprised of either a tongue or a groove along a side of a perimeter; the tongue formation including the second foam-setting fused thermoplastics material; each member 60 of the set thereby being capable, when in use, of joining to adjoining members; said interlocking joints being capable of being held together by at least one of adhesive fastening means and physical fastening means.

In one major option each member of the set is moulded into the shape of a triangular prism and is capable of being interlocked with other members of the same set by means of 65 moulded interlocking joints around three sides of the perimeter of each member.

In a more conventional major option each member of the set is moulded into the shape of a cube and is capable of being interlocked with other members of the same set in two perpendicular axes by means of interlocking joints around four sides of the perimeter of each member; two adjoining sides being configured as either a tongue or a groove. 70 In a related aspect, each member is a wall panel selected from a range comprising: rectangular wall panels having a domed external surface and rectangular outer wall panels having an environmentally resistant external surface and rectangular panels having a domed and environmentally resistant external surface.

In an option, a portion of the externally directed skin of the component is comprised of a 75 fused mass formed by heating and melting a second selected non-foaming type of thermoplastics granule within a heated mould while not fully rotating the mould.

In an option, at least some members of the set are rectangular wall panels having a height equal to a height of the wall.

In another option, at least one member is a wall panel providing at least one aperture; the 80 member being selected from a range including window apertures and door apertures.

In a further option, at least one member is a corner pillar having a height equal to a height of the wall and including interlocking joints along both long edges.

In a yet further option, at least one member is an elongated roof tile including interlocking joints along both long edges and having an outwardly concave exterior skin. 85 In a second broad aspect the invention provides a polyhedral construction or building wherein the construction or building is comprised of prism-shaped members of the set as previously described in this section.

In a third broad aspect the invention provides a cubic or rectangular construction or building characterised in that the walls of the construction are comprised of cube-shaped 90 members of the cubic set as previously described in this section; each wall being joined to other walls at corners by corner pillars as previously described in this section, and covered by a roof comprised of roof tiles as previously described in this section.

Preferably the components are held together at the tongue and groove joints using at least one of the following fastening means: 95 a) Physical fasteners which traverse the joint, thereby holding the components to each other, b) Physical fasteners moulded into the joints, selected from a range including mating lugs and sockets, c) Adhesives or glues selected from a range including solvent glues, two-part glues 100 such as epoxies, and glues which become active when dried, d) Localised application of heat, thereby locally melting the components on to each other, including heat from a heat gun, from an ultrasonic generator, from an included hot wire, or from a reversibly penetrating hot object.

Preferably the physical fasteners are capable of being undone, so that after a period of use 105 a fabricated building may be disassembled and removed.

PREFERRED EMBODIMENT The description of the invention to be provided herein is given purely by way of example and is not to be taken in any way as limiting the scope or extent of the invention. 110 Throughout this specification unless the text requires otherwise, the word "comprise" and variations such as "comprising" or "comprises" 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. Each document, reference, patent application or patent cited in this text is expressly incorporated herein in their entirety by reference. 115 Reference to cited material or information cited in the text should not be understood as a concession that the material or information was part of the common general knowledge or was known in New Zealand or in any other country.

DRAWINGS Fig 1: shows an oblique perspective view of part of a building including illustrative 120 members of the mutually interlockable set.

Fig 2: shows a different aspect of that part of a building.

Fig 3: (as Figs 3a, 3b and 3c) illustrates an example half-height block. Fig 3d shows a block in cross-section.

Fig 4: shows detail of a screwed joint. 125 Fig 5: shows detail of a roof tile; lateral view.

Fig 6: shows detail of a roof tile; underneath view.

Fig 7: shows detail of a roof tile, from the downward side.

Fig 8: shows detail of a corner pillar from the groove joint side.

Fig 9: shows a triangular wall block having two tongue sides and one groove side. 130 Fig 10: shows part of a polyhedral enclosure suitable for use as a dwelling and made of tiles such as shown in Fig 9.

Fig 11: shows an isometric view of full panel height components.

Fig 12a and 12b show in elevation and plan a small building constructed from full panel height components of the types shown in Fig 11. 135 Fig 12c illustrates the building of Figs 12a and 12b in exploded view.

EXAMPLE 1 Each member of the set of mutually interlockable components for use in the construction of a building is, according to the invention, comprised of fused thermoplastics material. 140 Preferably all parts are manufactured by forming in a single-axis rotational moulding type process within moulds. Movements other than simple single-axis rotation may be used.

The interlockable components provide a set of rectangular or cubic interlockable wall blocks rather like bricks or concrete blocks, including a set of standard sized blocks, a set of half-sized blocks, a set of corner pillars, and a set of roof panel tiles that are intended 145 for use in the construction of a building. Each component has a length, a width, and a thickness and conforms to a set of mutually standardised dimensions at least with respect to an interlocking or joining portion of each component. It is also convenient for those standardised dimensions to conform to local building practices. It is preferred that all parts in the range can be joined together at compatible interlocked joints. They share a common 150 coupling means or joint mechanism, having consistent dimensions. The parts may be approximately square or rectangular as bricks or concrete blocks are, or may be elongated such as those shown in Figs 11 and 12 - a, b and c; subject to the internal dimensions of a manufacturing oven. Note that the preferred elongated roof tiles are not truly “cubic” because each tile includes a dished cross-section. The tiles are intended for side-by-side 155 and joined-together assembly with the channel along the median axis of each dish directed along a downwards slope.

Each member is made by rotational moulding techniques within moulds and hence is comprised of a compatible thermoplastics material. An example fusible plastics material is a polyethylene plastics material; for example ICORENE 3840 made by ICO Polymers, Inc 160 of 6355 Farm Bureau Rd, Allentown, PA 18106, USA. This is a Linear Medium Density Polyethylene plastic material. Various resins with different characteristics may be used, such as alloys based on the same ethylene with varied co-monomer (hexene, butene or octene) raw materials, as is known to those skilled in the art. Such materials are obtainable in both solid-setting and foam-setting versions. Preferred moulding temperatures are 165 between 180 and 280 degrees Celsius. The preferred single-axis rotational moulding process has been described in at least (WO/2008/133535), in which the present applicant has developed the capabilities of the generic rotational moulding process towards making large, flattened or angled sheets of materials including more than one layer of plastics. A typical component that has been made in this way has a hollow or 170 attenuated centre surrounded by a tough, formed skin which had been in contact with the walls of the mould and is suitable for internal or external exposure. The hollow or attenuated centre is preferably occupied by thermal insulation which may be filled with a less dense, foamy yet rigid fused thermoplastics material made from a foam-generating type of granules. The centre may be comprised of a space. The space may contain a stored 175 liquid. Of course, components made by other processes or made from natural products such as wood may be incorporated with the rotationally moulded components. Optionally each tile is provided with internal insulation means selected from a range including a more foamy plastics material, animal or vegetable fibre, or rock or glass wool. 180 WALL COMPONENTS Figs 1 and 2 show oblique perspective views of part of a building 100, made from components created in a rotational moulding machine. The roof 102 is incomplete, for the purpose of illustration. There is a channel 106 (fig 2) that provides a footing or foundation for the wall, which might be formed in concrete or in metal. The walls 101 (and 101A in 185 Fig 2 only) are comprised of an array of interlockable rectangular blocks for example 110, 110a and 110b as detailed below, which are fitted tightly together during assembly by sliding tongue 113 projections into grooves 114 in order to create joints, (details of which are given below) in order to make a sufficiently large plane surface wall. Fig 1 shows an opening 103 for a door and another opening 104 for a window. The door has a lintel 190 comprised of a half-height block 111. That block has tongues on each side (not shown).

Preferably, all borders of the door are groove joints, as shown in Figs 1 and 2. A corner pillar 105 – see also fig 8 - is a length of material fitted with sufficient tongue joints along one side and groove joints along another side to accommodate the joints of several blocks; such as a three-high stack. As such the corner pillar is a member of the mutually 195 interlockable set of rectangular components. The corner pillar separates wall 101 from another, end wall 101A in a perpendicular plane. Half-width blocks 115 are used alternately to commence every second course of wall blocks since the usual method of construction, like a brick wall, uses overlapping courses of unit blocks in order to provide strength. This assembly as described does not include internal vertical concrete and iron 200 bar reinforcing although holes could be bored through the hollow or attenuated centres and parallel to the outer walls, for insertion of steel or other tensile rods if required by a building code. The wall is seated upon a channel member 106. A roof 102 is comprised of an array of elongated roof units, as detailed below.

Fig 3 (as Figs 3a, 3b and 3c) provides dimensional details and detailed orthogonal views 205 of an example half-width (800 x 400 mm) block. It should be noted that the dimensions (given here in millimetres) corresponding to a series of standard blocks presenting an exposed surface of 800 x 800 mm are by way of example only, and do not in any way limit the range of sizes to be provided for by the invention. For instance dimensions may be arranged to correspond with the popular 1.2 metre multiples commonly used by 210 builders, although the 800 mm size conforms to a typical door width. The popularity of any one size may in part be dictated by the cost (which may be affected by a rejection rate) of manufacturing individual units. The depth or height of the tongue and groove joints is partially affected by a desired final assembly strength. Preferably the depth of a groove is slightly greater than the height of a tongue. 215 One preferred style of block is moulded so as to be substantially hollow.

Details of a preferred joint arrangement will now be described. Fig 3 includes example measurements in millimetres for parts 3a and 3b. Fig 3(a) is an edge elevation view of an interlockable block version along one edge, wherein 301 is a groove or recess across the face extending towards a viewer out through the plane of the drawing. 220 The dimensions given, by way of example only, in this drawing show: An 800 x 400 (usable area) block which has a thinner tongue extending from two adjacent edges by 70 mm. The thickness of the block is 170 mm; the thickness of the tongue is 148 mm, leaving 10-11 mm on each “tongue cover” around the 70 mm deep recesses on the other two adjoining edges. These tongue dimensions are adequate for the material from which 225 the blocks have been constructed – namely a fused thermoplastics material.

When assembled, each groove or recess 114 would receive a tongue 113 of an adjacent block. Blocks may be glued together although they may also be screwed together for the benefit of easier installation and easier disassembly (see later). 304 is one face, perhaps an exterior face, of the block and 302 is the opposite face. (In some cases, both faces will be 230 interchangeable, although it may be preferred that one face will be adapted for exposure to weathering and will include a dye or pigment, or other additives for extending the life of the block when exposed to weathering. The inventor’s moulding process (see below) provides an optional step for applying a different thermoplastics mixture to each side.) 303 indicates an indexing groove, which may receive an extended width portion of the 235 protruding tongue of another block. This is mainly useful during assembly as a temporary locating means. Fig 3(b) which includes measurements shows a tongue 306 across the face of the opposite edge elevation of a block and extending towards a viewer out through the plane of the drawing.

Fig 3c is a face view of a typical block, showing dimensions, and provision of tongues 240 along two adjoining edges. 302 is one face of the block. 305 and 306 are two tongues.

Fig 3d shows a preferred domed surface 307 on the outer (exposed) surface of a cross- sectioned wall block. This dome, formed by a dished shape in one face of the mould, provides for controlled thermal expansion of the dome when heated, such as by sunlight.

If the outer surface is left flat then expansion and contraction are not controlled and the 245 entire block may bend. Materials thickness may be exaggerated in this section. Other parts are as previously identified. The internal void may be filled or more preferably is filled with a foamed, fused thermoplastics mass.

ROOF TILE COMPONENTS Figs 5, 6 and 7 show a single one of the array of roof tiles 112 that form the partially 250 completed roof 102 of the building in Fig 1. It could be said that the roof tiles comprise members of a different set, since they are visually not truly cubic and their structure is determined by their function. On the other hand, their dimensions are dictated by a requirement to fit, when inclined at an angle, over walls that are comprised of members of the previously described mutually interlockable set of rectangular or cubic components. 255 Fig 5 is a longitudinal section, showing the hollow interior 506 of the roof tile which is adapted for side-to-side joining to other such tiles thereby forming an array, with fastening as described elsewhere in this section. Each of these tiles is intended to span over half a roof from the ridge along the middle and so the length of the selected tile determines the size of the room below. However these tiles can be joined end to end; 260 preferably in a waterproof manner and supported on intermediate purlins parallel to the ridge. Fig 7 shows details of a tile coupling arrangement 502, 505 to be optionally provided on ends of tiles. Conventional flashing along the ridge of the roof is useful, depending on the environment. Each tile includes a transverse groove 503 (see Figs 5 and 6) intended to be placed over and attached to the top course of the wall blocks, near the 265 lower end 505 of the tile 112. The angle of this transverse groove, which is formed obliquely into the underside of the tile, partially determines the angle of the tiles from a vertical plane – since as shown in Fig 1 this groove sits over the top of the wall. Fastening means as described elsewhere in this section is intended to be used to fix the tiles down to the wall, and at free surface 501, to another array of tiles. The surface facing the sky, 502, 270 is dished inward, partly for strength and partly to assist in water collection. (No gutter or spouting arrangement is shown here) The underneath surface shown in fig 6 is dished outward, up from the plane of the drawing. The space underneath the tiles may, during construction, be packed loosely with a fibre such as animal hair or wool that is held in place with (for example) wire netting in order to increase the thermal insulation of the 275 roof.

CORNERS An example of a corner pillar 105 is shown in Figs 1 and 2 at 105, and in detail in Fig 8.

This example is shown from one side – the “groove” side 114. This drawing shows the essentially hollow nature of the corner pillar which structure can be achieved with 280 rotational moulding, thereby providing a relatively light yet strong pillar. The opening 114 might be strengthened for transport with inserted blocks although, once assembled, the edges are held apart from each other by the assembled tongues of the wall tiles (see Fig 3a, 3b or 3c) that are fixed within. The protruding blocks such as 113 are the “tongue” elements intended to mate with corresponding grooves of each of three courses of wall 285 blocks such as 110 in Fig 1.

FASTENERS For purposes of construction, the components are held together with one or more of the following preferred fastening means: a. Physical fasteners which traverse the joint, thereby holding the components to 290 each other. This option allows deconstruction after the building has been used in one place, in anticipation of it being needed elsewhere. Fig 4 shows an example of physical fasteners, namely screws 401 and 402 in a section across a joint between blocks 110 and 110a. b. Physical fasteners may be moulded into the joints, selected from a range including 295 mating snap-in lugs and sockets. For disassembly, apertures that allow a tool to be inserted and then press back the lugs might be provided (not shown). c. Plastics glues selected from a range including solvent glues, two-part glues such as epoxies, and glues which become adherent when dried. d. Localised application of heat, thereby locally melting the components on to each 300 other, including heat from a heat gun, energy from an ultrasonic generator, heat from an included hot wire, or heat from a reversibly penetrating hot object. e. Rope, twine, or plant fibre, or rawhide may be used to bind the structure together.

Holes for passing the bindings through the tiles to be bound together are not shown. Such holes may be made during assembly. 305 EXAMPLE 2 The previous Example assumed rectangular members or components; combined together as rectangular parts of a building. If the components are instead triangular blocks, and are joined together securely yet allowing the surface plane of any one triangular block to differ from that of adjoining triangular blocks, it is easy to fabricate polyhedral dwellings 310 as popularised by the architect Buckminster Fuller. They have no distinct roof assemblies.

Fig 9 shows a face view of an example triangular block 900 having two tongue edges 901, 902 and one groove edge 903. About half of the triangular blocks will require one tongue edge and two groove edges. The other half will require one groove edge and two tongue edges. Fig 10 shows a portion of a polyhedral assembly made from triangular blocks 900. 315 The groove aspects of two of the blocks can be seen in Fig 10 at 1001, which also show the appreciable thickness of each individual triangular block.

EXAMPLE 3 Example 1 assumed that rectangular components would have a length to height ratio not greatly beyond 2:1, and the members would interlock both horizontally and vertically, like 320 bricks or concrete blocks, to form a desired vertical wall height. Given a sufficiently long oven, the preferred manufacturing process allows many of the components to instead be manufactured as full-panel-height members each having the same height as the finished wall. Even as full-height (for instance 2.4 metres in length) the hollow or foam-centered components are not too heavy to carry and to place in position. See Fig 11, which in an 325 “exploded view” depicts two full height wall panel components (120) aligned to interlock with the corner column (105). A finishing full height component (130) is provided for use where a narrower wall section is desired, for example as a frame for a door or a window.

The full-panel-height members preferably conform to the same standardised surface and joint dimensions as for the Example 1 members, for greater design freedom. 330 As an illustrative example, a small worker’s accommodation built from such full panel height components is shown in Fig 12a (elevation view), 12b (plan view), and 12c as exploded view of components 600. Fig 12c includes: floor panels 122, cutout wall panels 121 for use in framing a window, a window lintel 123, a door lintel 111, and two door frame components 130. 335 METHOD The principles of this component manufacturing method have been described previously by the inventor, but some modifications, and the shapes of the moulds are novel. An example method for manufacture of interlockable components according to the invention includes appropriately shaped moulds for individually forming each members of the set, 340 and optionally includes the finishing step (h) as below: a. making an openable and releasable mould which can conduct heat into the interior for each distinct shape of component, and which maintains access for the introduction of granules into the interior of the mould when being rotated during use; 345 b. heating an oven to a working temperature – which is related to a softening temperature for the selected thermoplastic material, typically between 180 and 280 degrees Celsius; c. placing each mould in the oven and heating it to a selected temperature; d. introducing a first granular non-foaming thermoplastics material while rotating the 350 mould for a time so that all parts of the mould become internally coated with fused thermoplastics material; e. optionally then introducing a foam-generating inner thermoplastics material while continuing to rotate the mould so that an inner void within the mould become internally coated with the thermoplastics material; 355 f. after a time removing each mould and allowing it to cool; g. opening the mould; h. and optionally trimming at least the mating joint surfaces of each component once moulded and cooled using a cutting tool – such as a saw or an end mill along with a holding vice or jig - so that its dimensions become fully controlled regardless of 360 shrinkage or sagging.

Many of the components described here could not be made in a two-axis, closed mould.

The temperature is best set by experience. Too low a temperature will lead to extended fusion times, and too high a temperature causes decomposition of the plastic. The readings are dependent on transducer placement. Of course the temperature also depends 365 on the selected plastics material.

The preferred variation at the step (e) provides each component with improved thermal insulation and extra mechanical strength without much increase in weight.

Another variation which is possible with a single-axis rotational moulding process usable at the step (d) includes (d1) placing a first variation of a non-foaming granular mixture on 370 a first face of a tile or the like, fusing it in place while agitating or only partially rotating the mould, and then (step d2) rotating the mould through 180 degrees, introducing a second non-foaming granular mixture into the mould, and then commencing single-axis rotation of the mould, so that the second mixture tends to coat the remainder of the inner surface of the mould. That modification causes the external surface of the member to have 375 a different composition optimised for resistance to weathering, such as one including a pigment (for example titanium dioxide for white, iron oxide for red, or carbon for black).

It will be appreciated that these components are easily stacked for transport, such as on pallets or in containers. 380 VARIATIONS Some of the components, especially the elongated ones shown in Figs 11 and 12 might be made economically by plastics extrusion techniques. In this variation, an extruded box section including the groove joint along two adjacent edges and the tongue joint along one edge is made. Post-processing includes the steps of cutting out squares at for example 800 385 mm spacings along the box section, inserting and gluing into place a separately made tongue section so that the completed block bears a tongue joint component along two adjacent edges.

Doors and windows themselves have not been described, but may be made from plastics or wood or glass, and may be replaced by simple curtains in some circumstances. 390 The channel 106 that provides a footing for the wall may be made from a metal.

Exposed surfaces may be painted, for example with white paint for thermal resistance.

In order to reduce the total consumption of plastics, a stone aggregate may be mixed with the thermoplastics material for moulding at least some of the components.

Optionally at least some of the components are comprised of a material based on concrete 395 rather than a thermoplastics material.

The plane surfaces of the wall blocks previously described in this section may be replaced by curved surfaces; preferably curved in more than one plane at one time, so that increased strength per unit of weight is provided. Apart from the domed walls previously described in this section, one version of this would appear like corrugations with a pitch 400 of perhaps 50 mm.

RESULTS AND ADVANTAGES This invention provides prefabricated components for buildings, so that a building can be carried to a site as individual or aggregated components as dictated by the transport facilities available, then erected at the site. Optionally, the parts for the building are 405 temporarily attached, but are not fused together permanently, so that the building can be taken down when no longer required, and used again elsewhere.

The inventor believes that these buildings may be of particular use as housing for disaster relief or for providing shelter to homeless persons.

Finally it will be understood that the scope of this invention as described and/or illustrated 410 herein is not limited to the specified embodiments.

Claims (10)

1. I CLAIM: 415 1. A mutually interlockable set of components for use in building construction characterised in that the or each member of the set is a single, moulded component having a width and a height and a thickness; all members of the set having compatible physical dimensions and having interlocking joint formations selected from a range of a tongue and a groove; each member being completely encased within an outer skin 420 extended over both outer surfaces; the outer skin comprising all surfaces of the joints and comprised of one or more first solid-setting fused thermoplastics materials; the skin enclosing an attenuated interior volume comprised of a second foam-setting fused thermoplastics material; the joint formation comprised of either a tongue or a groove being located along a side of a perimeter; the tongue formation including the second 425 foam-setting fused thermoplastics material passing into an interior of the tongue; each member of the set thereby being capable, when moulded, of forming interlocking joints with other members of the set.
2. 2. A mutually interlockable set of components as claimed in claim 1, characterised in that each member of the set is moulded into the shape of a triangular prism and is 430 capable of being interlocked with other members of the same set by means of moulded interlocking joints around three sides of the perimeter of each member; said joints being capable of being secured by at least one of an adhesive fastening means and a physical fastening means.
3. 3. A mutually interlockable set of components as claimed in claim 1, characterised in 435 that each member of the set is moulded into the shape of a rectangular panel having two pairs of mutually perpendicular edges and an interior volume and is capable of being interlocked with other members of the same set in two perpendicular axes by means of interlocking joints around four sides of the perimeter of each member; two adjoining sides being configured as either a tongue or a groove; said joints being capable of being 440 secured by at least one of an adhesive fastening means and a physical fastening means.
4. 4. A member of the set of components as claimed in claim 3, characterised in that the member is selected from a range comprising: rectangular wall panels having a flat external surface; rectangular wall panels having a domed external surface and rectangular outer wall panels having an environmentally resistant external surface and 445 rectangular panels having a domed and environmentally resistant external surface.
5. 5. A member of the set of components as claimed in claim 3 4, characterised in that the member is a rectangular wall panel having a height equal to a height of a wall.
6. 6. A member of the set of components as claimed in claim 3 4, characterised in that the member is a wall panel providing at least one aperture; the dimensions of the aperture 450 being selected from a range capable when in use of providing window apertures and door apertures.
7. 7. A member of the set of components as claimed in claim 3, characterised in that the member is a corner pillar having a height equal to a height of a wall and including interlocking joints along both long edges. 455
8. 8. A member of the set of components as claimed in claim 3, characterised in that the member is an elongated roof tile including interlocking joints along both long edges and having an outwardly concave exterior skin.
9. 9. A polyhedral construction or building characterised in that the construction is comprised of members of the set as claimed in claim 2. 460
10. 10. A rectangular construction or building characterised in that the walls of the construction are comprised of members of the rectangular set as claimed in claim 3, joined to each other at corners by corner pillars as claimed in claim 7, and covered by a roof comprised of roof tiles as claimed in claim 8.