Background

Traditionally, building of bathrooms or other wet areas, whether on-site or in a modular construction, is "static", i.e. there is an established consecutive order to the building process. In particular, construction of walls and floors of such wet areas comprises installation firstly of supportive framework, application of a substrate to the installed framework, waterproofing of the applied substrate, then application of a covering or finish, typically comprising tiles, over the waterproofed substrate. Formation of tiled finishes, to accommodate dimensional variations resulting from all of the preceding activities, requires tiles to be individually laid out and fixed in position, and edge tiles to be "cut-in" to suit individual locations. As a result of this, as well as much of the wall and floor fabrication being in situ in a building or building module, construction of the building/module is time-consuming.

Summary of the Invention

According to a first aspect of the present invention, there is provided a prefabricated panelised or panel unit for forming part of a building, the unit including a waterproof membrane to preclude passage of moisture through the unit, the membrane including at least one exposed portion, the or each exposed portion being attachable to a respective component adjacent to which the unit is to lie in the building, such that a seal is formed across a junction between the unit and that component in the building. Preferably, the unit is for forming a wall, ceiling or floor, or part thereof in the building.

The unit according to a preferred embodiment of the invention includes a support structure and a covering or finish applied over the support structure so as to be supported by it, the membrane being arranged between the support structure and the covering or finish to preclude passage of said moisture from the covering or finish to the support structure. Preferably, the covering or finish comprises tiling. Alternatively or additionally, the covering or finish may comprise sheeting, e.g. polymer sheeting, such as vinyl sheeting. Alternatively or additionally, the covering or finish may comprise a coating, such as paint, which may be especially appropriate where said unit is for forming a ceiling or part thereof, in which case it may be appropriate that the substrate comprise plasterboard.

In the unit according to a preferred embodiment of the invention, the covering or finish defines the entirety of a covering or finish applied over the support structure in the building.

In the unit according to a preferred embodiment of the invention, the support structure comprises a substrate to which the membrane is applied. The substrate may comprise, for example, any one or more of fibrous sheeting, cementitious board, plasterboard and engineered board such as plywood or medium-density fibreboard (MDF). Alternatively or additionally, the substrate may comprise glass-reinforced concrete (GRC) or a similar substrate which is moulded. In the unit according to a preferred embodiment of the invention, the support structure comprises a frame. The frame may comprise a timber frame. Alternatively or additionally, the frame may comprise a metal (e.g. steel) frame. Alternatively or additionally, the frame could comprise a moulded frame, especially where the unit is for forming a floor or part thereof, which moulded frame could be formed, for example, from GRC. Preferably, said substrate is applied to said frame so as to be supported by it. It is conceivable that the membrane, alternatively, be applied directly to the frame. For example, the membrane could comprise a sheet of material having sufficient rigidity that the said substrate is not required. Said material may, for example, comprise metal (e.g. steel, preferably stainless steel) or a polymer. In one embodiment of the invention, the unit is for forming said ceiling or floor, or said part thereof, and the frame comprises joists.

In a preferred embodiment of the invention, the or each exposed portion projects from under a respective edge of the covering or finish.

Preferably, the unit is for forming said floor or said part thereof. The unit may be configured with a grade to facilitate drainage of fluid over the floor.

Preferably, the or each exposed portion is a flap.

Preferably, the or each exposed portion is flexible.

In the unit according to the preferred embodiments of the invention, the membrane comprises a portion underlying the covering or finish and said exposed portion. Preferably, the portion underlying the covering or finish is defined by, or comprises, a sheet or coating, the sheet or coating preferably being applied to the substrate. The sheet or coating may comprise a polyurethane, vinyl or other polymeric sheet or coating.

In a preferred embodiment of the invention, the exposed portion is defined by a section, preferably a strip, applied to the sheet, to the coating or to the portion underlying the covering or finish. Preferably, said section is defined by tape or bandage, e.g. wet seal tape or bandage, as will be known to a person skilled in the art. The section may comprise, for example, polyester fabric. Said section may be applied to said sheet, coating or portion with a sealer, e.g. rubberised sealer.

In an alternative embodiment of the invention, where the portion underlying the covering or finish comprises, or is defined by, said sheet, it may be that the sheet is unitary or of single-piece construction and an edge portion thereof defines said exposed portion. (The membrane may possibly then be of unitary/single-piece construction in its entirety.) The membrane may comprise a sheet of material, which material may comprise metal. In one embodiment of the invention, sheet comprises a steel sheet. Preferably, the steel comprises stainless steel.

According to a second aspect of the present invention, there is provided a construction method comprising installation of said unit in the formation of said building, the method including attaching the or each exposed portion to a respective said component to form a respective said seal.

In a preferred embodiment of the invention, a said component is itself a prefabricated panelised or panel unit. That unit may define a wall, ceiling or floor, or part thereof, in the building. That component may, like a preferred embodiment of the unit of the first aspect, comprise a support structure ("the component support structure"), to which the exposed portion is to be attached, and may further comprise a covering or finish ("the component covering or finish"), which may comprise, for example, tiles, sheeting or skirting, applied over the component support structure so as to be supported by the component support structure. Preferably, the attachment of the or each exposed portion comprises attachment of that portion to a respective exposed face of the component support structure. Preferably, the method includes, after the attachment of each exposed portion, applying a covering or finish which may comprise, for example, tiles, sheeting or skirting, over the exposed portion and the exposed face to which that portion is attached. That covering or finish may match or be compatible with said component covering or finish.

In a preferred embodiment of the invention, the component support structure comprises a substrate ("the component substrate") defining said exposed face. In a preferred embodiment of the invention, the support structure comprises a frame. The component support structure may comprise a frame ("the component frame"). The frame may define said exposed face. Alternatively, said component substrate, applied to the component frame, may define the exposed face. In one embodiment of the invention, the unit is for forming said ceiling or floor, or said part thereof, and the frame comprises joists.

Preferably, the unit and component form part of a wet area in the building. The wet area may be, for example, a bathroom, kitchen or laundry.

The component may, alternatively or additionally, be, for example, an appliance or item of furniture or joinery, e.g. a toilet or sink unit, vanity unit, integrated bath or shower etc.

In the construction method according to one embodiment of the invention, the installation of said unit and the attachment of said exposed portion to said component are in an in situ formation of said building. In the construction method according to an alternative embodiment of the invention, the installation of said unit and the attachment of said exposed portion to said component are in the formation of a module to form part of said building.

In a preferred embodiment of the invention, a said component is itself a prefabricated panelised or panel unit. That unit may define a wall, ceiling or floor, or part thereof, in the building. That component may, like a preferred embodiment of the unit of the first aspect, comprise a support structure ("the component support structure"), to which the exposed portion is to be attached, and may further comprise a covering or finish ("the component covering or finish"), which may comprise, for example, tiles, sheeting or skirting, applied over the component support structure so as to be supported by the component support structure. Preferably, that covering or finish defines at least 25% of a covering or finish applied over the component support structure in the building. Preferably, that covering or finish defines at least 50% of said covering or finish applied over the component support structure in the building. Preferably, that covering or finish defines at least 75% of said covering or finish applied over the component support structure in the building. Preferably, that covering or finish defines most of said covering or finish applied over the component support structure in the building. Preferably, the attachment of the or each exposed portion comprises attachment of that portion to a respective exposed face of the component support structure. Preferably, the method includes, after the attachment of each exposed portion, applying a covering or finish which may comprise, for example, tiles, sheeting or skirting, over the exposed portion and the exposed face to which that portion is attached. That covering or finish may match or be compatible with said component covering or finish.

According to a third aspect of the present invention, there is provided the module formed via said method.

According to a fourth aspect of the present invention, there is provided the seal formed by said method.

According to a fifth aspect of the present invention, there is provided the building formed via said method. According to a sixth aspect of the present invention, there is provided a prefabricated panelised or panel unit for defining a said component adjacent to which said unit according to the first aspect is to lie in the building.

According to a seventh aspect of the present invention, there is provided a method of fabricating said building unit, comprising arranging said membrane such at it is secured between the support structure and the covering or finish.

The method of the seventh aspect preferably includes applying the membrane over said substrate.

The method of the seventh aspect preferably includes applying the covering or finish over the membrane subsequent to application of the membrane over the substrate.

The method of the seventh aspect preferably includes applying the substrate over the frame. Preferably, application of the substrate over the frame precedes application of the membrane to the substrate.

Brief Description of the Drawings

The invention will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Figures 1 to 10 show successive stages in a typical construction of a bathroom pod employing conventional methodology;

Figures 11 to 14 show successive stages in the fabrication of a floor unit for the bathroom pod in accordance with a preferred embodiment of the present invention; and

Figure 15 shows installation of the floor unit and other components in the construction of the bathroom pod in accordance with a preferred embodiment of the present invention. Detailed Description of the Preferred Embodiments

Figures 1 to 10 depict successive stages in construction of a bathroom module or "pod" involving traditional methodology. Such a pod is typically constructed off-site and then transported and installed into a building structure. The traditional construction of the pod, referring to Figures 1 to 3, commences with fitting one or more floor frames 1, to a frame 50 (being either a temporary support structure for fabrication of the pod or a structure to which the pod is to be applied), the/each floor frame comprising opposed beams 3 and joists 5 extending between the beams 3. Referring to Figures 3 and 8, the number of floor frames in the present example is two, the floor frame 1 being for a shower area of the pod and the floor frame being for the remaining area of the pod, which area includes components in the form of appliances and furniture, namely a toilet and a vanity unit respectively, a drain 60 being installed between the floor sections of the two areas. Referring to Figure 4, a substrate 7, such as board material as mentioned above, is applied over the/each installed frame 1/1 '. Once the/each layer of substrate has been installed, a waterproof membrane layer is applied over that layer. The membrane layer, which functions as a wet seal, may comprise a sheet or coating applied to the substrate, which sheet or coating may be polyurethane, vinyl or other polymeric material. The sheet or coating may comprise a product named Gripset GC Wetseal, available from Gripset Industries Pty Ltd in Australia. A respective covering or finish 9 (see Figure 5), typically comprising tiles, is then applied over the membrane layer. The/each covering or finish layer stops short of each edge of the substrate 7 to which it is applied, whereby perimeter portions of the upper face of the substrate layer remain exposed. Next, referring to Figures 6 and 7, wall sections 20 are constructed. Construction of each of the wall sections 20 is similar to construction of each floor section 10 in that firstly a frame of the wall section 20 is installed, a lower end of that wall section being received against a portion of substrate 7 (not covered over by the covering/finish 9) or directly against the frame 1/1 ' (not covered over by the substrate 7) of the floor section 10 secondly a substrate is applied over that frame, thirdly a membrane layer is applied over that substrate, and fourthly a covering or finish, typically comprising tiling, is applied over that membrane layer (though, in other embodiments, the wall section 20 need not include a membrane/membrane layer). The covering or finish 29 stops short of the edges of the substrate, or of the membrane layer applied to that substrate, such that a peripheral portion of the face defined by that membrane layer/substrate is exposed. Each junction between adjoining floor/wall sections 10/20 must be waterproofed. To this end, a connective flexible strip is attached to adjacent exposed portions of the membrane layer/substrate faces in the adjacent sections 10/20 and "mudded in", so as to be attached to those face portions, whereby there is formed a waterproof bridge sealingly connected to the membrane layers in the adjacent sections 10/20, the waterproof bridge providing a "bond breaker". Once the compound has set/cured, whereby the waterproof bridge has been formed across the respective junction, a covering or finish is applied to each of the adjacent sections so as to cover the bridge and the exposed surfaces of the membrane layer and/or substrate to which the bridge is adhered. Figures 9 and 10 depict stages in installation of an exterior wall of the pod, a portion of which wall defines part of a wall of the bathroom/wet area. In the first stage, shown in Figure 9, a wall section, comprising a frame, a substrate applied to the frame, and a membrane layer applied to the substrate, is fitted such that the membrane layer abuts or lies closely adjacent opposed previously formed wall sections in the shower area, in each of which previously formed sections the covering or finish stops short of the edge of that wall section abutted by the exterior wall section, and also abuts or lies closely adjacent the floor section 10. In the second stage, shown in Figure 10, a covering or finish, typically comprising tiling, is applied over the membrane layer of the exterior wall section. The covering or finish in the exterior wall section stops short of the previously formed shower area wall sections and the floor section 10 which that exterior wall section abuts or to which that exterior wall section lies closely adjacent. Flexible strips, of the kind previously described, are then applied, in the manner previously described, to adjacent resultant exposed portions of the membrane layer/substrate faces in the adjacent sections, whereby waterproof bridges cover junctions between those portions. A covering or finish is then applied to each of the adjacent sections so as to cover the bridge and the exposed surfaces of the membrane layer and/or substrate to which the bridge is adhered.

Typically, the coverings/finishes applied over the waterproof bridges comprises narrow/small tile sections, which must be cut out of larger tiles to fit the edge areas at which they are applied. Cutting of the tile sections is labour-intensive and must be in accordance with measurements which will differ from one pod to the next because of manufacturing tolerances, so that installation/completion of the floor and wall sections is time-consuming. Time consumption is exacerbated by the fact that so much of the construction of each of the floor and wall sections is in situ. The preferred embodiments of the invention significantly reduce time consumption.

Waterproof bridges, of the kind previously described, are applied across each junction between a given floor or wall section 10/20 and a component (such as another such section, an item of furniture, a drain etc.) adjacent to that section in the pod. Such bridges are therefore formed at wall section- wall section junctions, wall section-floor section junctions, wall section-furniture junctions, floor section-furniture junctions, floor section- drain junctions, etc. It is also possible that wall section-ceiling waterproof bridges may be necessary. Manufacture and installation of a floor unit 100, shown in Figure 14, and associated wall units 20', shown in Figure 15, in accordance with a preferred embodiment of the present invention, owing to which construction of the pod is simplified and hastened, will now be described, using the same reference numerals to refer to features corresponding to or the same as aforementioned features shown in Figures 1 to 10.

Fabrication of the unit 100, referring to Figure 11, commences with formation of the frame 1, comprising end beams 3 and joists 5. In the present example, the unit 100, because it defines the shower floor section, is configured with a grade such that water from the shower flows, over the shower floor, to the drain 60. To this end, referring to Figure 12, packers 11 A, 11B of progressively increasing thickness are applied to successive ones of the joists 5.

Thereafter, the substrate 7 is applied over the frame 1, as shown in Figure 13. Referring to Figure 14, a membrane portion is applied to the substrate, the membrane portion comprising a sheet or coating - e.g. a polyurethane or vinyl sheet or coating. Thereafter, strips of wet seal tape or bandage (which may be polyester), as will be known to a person skilled in the art, are applied to the sheet or coating, using a sealer, such as rubberised sealer, which sealer may, where the membrane portion is defined by said coating, actually form the coating. After the sealer has set/cured, whereby the strips have been "mudded in", a covering or finish 9 is applied, with adhesive, over the membrane portion, whereupon fabrication of the unit 100 is complete. The unit 100 includes a membrane 8, comprising the sheet/coating and the strips thus applied thereto, each strip defining a respective exposed flap 30 of the membrane 8. The flaps 30 project from between the covering or finish 9 and substrate 7 along edge portions of the support structure defined by the substrate 7 and frame 1, one such flap 30 being clearly shown in Figure 14. The building unit 100, unlike the shower floor unit shown in Figure 5, is formed ex situ and defines the entirety of the shower floor section; more particularly, the covering or finish 9 provides the entirety of the shower floor surface. Each flap 30 is used to form a waterproof bridge, fulfilling the same purpose as the aforementioned waterproof bridges, as will be described in further detail shortly.

Fabrication of each wall unit 20', like that of the floor unit 100, is ex situ and, referring to Figure 15, comprises application of a substrate 27 to a frame 21, application of a waterproof membrane 28 to the substrate, and application of covering 29', comprising tiles, to the membrane 28. Each wall unit 20' defines almost the entirety of the wall section 20 of which it is to form a part, all that it lacks in this regard being a lowermost horizontal row of tiles or tile sections, whereby a portion of the waterproof membrane 28 which overlies the substrate 27 therein is exposed, and a vertical row of tiles or tile sections adjacent either or each side edge thereof, such that a respective strip of wet seal tape or bandage can be applied (in the manner described above) at a respective corner the wall section forms with an abutting wall section. When the floor unit 100 and wall units 20' are installed, respective flaps 30 of the unit 100 are received against the exposed membranes 28 of the wall units 20', as shown in Figure 15. The sealer is then applied to those flaps such that they sealingly bond to the respective portions of the exposed membranes 28, whereby the respective waterproof bridges over the junctions between the unit 100 and units 20' are formed. Likewise, when the exterior wall section and covering or finishing applied over it are installed, the flap 30 adjacent to that wall section is received against the exposed lower portion of the membrane of the exterior wall section, and the adhesive is applied to that flap such that it sealingly bonds to the exposed lower portion. The other flap 30 is mudded in to form a waterproof barrier under the drain.

Thereafter, final coverings or finishes, comprising lower rows of tiles or tile sections, are applied to the exposed membrane portions and the flaps 30 bonded to those portions, as well as to the aforementioned side edges, whereupon fabrication and installation of the opposed wall sections 20 is complete. Advantageously, the entirety of the section defining the shower floor, namely unit 100, and sections defining most of the opposed shower walls 20, namely units 20', are prefabricated, formation of the units 100 and 20' thus being off the critical path of the construction of the pod. The units can be prefabricated via the use of jigs, to tolerances which are tight as compared to conventional in situ fabrication. A given such jig may comprise an adjustable-height table upon which adjustments can be made to locate precisely the joists 3 or stud members 21 to a desired configuration, a guide to locate precisely pre-cut substrate sheets/panels 7 and 27, and/or a guide and device to aid/assist in precise location/placement of both the membrane 8/30 and finishes 9/29).

It will be appreciated that, in an alternative embodiment, the "complete" building unit may, instead of being the floor unit 100, be a wall unit which defines either of the opposed wall sections 20 and which includes a membrane-defined exposed flap, in which case the covering or finish in the prefabricated floor unit (unlike in the floor unit 100) will stop short of an edge of the substrate 7 in the floor unit which is to lie adjacent that wall unit, whereby the exposed flap is received against a thus exposed portion of the membrane applied over the substrate 7, the adhesive then being applied to that flap to mud it in, whereby the requisite waterproof bridge is formed between the floor unit and wall unit. After the adhesive/cures, a final row of tiles/tile sections is applied over the floor unit to cover the edge portion of the membrane in the floor unit and the flap which is thus sealingly attached to that portion. That said, it will often be preferable that it be the floor unit 100 which is the completed unit because the exposed membrane flaps, if part of a floor unit, less prone to damage during the building process, those flaps assuming an upstanding orientation as can be seen in the drawings. Although the flaps (along with substrate and finish surface) extend parallel to floor and substrate planes when formed, they can, being flexible/pliable, bend into an upright orientation to lie against the front surface of substrate of adjacent pre-finished wall panel units, whereby each flap automatically assumes the positions it occupies in the waterproof bridge of which it is to form a part (when mudded in).

In the preferred embodiments of the invention, the floor and wall sections - and possibly also one or more ceiling sections - are formed as prefabricated subassemblies, which can, as indicated above, be produced on jig to very tight tolerances, whereby pre-cutting/sizing of many of the materials forming the sections is enabled/facilitated. The sub-assemblies, advantageously, are produced Off-line' and therefore not on the critical path of the building/module.

The waterproof membrane in each building unit embodying the invention seals that unit and the junctions formed between that unit and adjoining/adjacent components. The methodology of the preferred embodiments of the invention facilitates post-placement "completion" of the wet seal membrane on the surface to which it is joined during assembly.

While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. It will be apparent to a person skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the present invention should not be limited by any of the above described exemplary embodiments. Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", 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.