GB2471779A

GB2471779A - Shower floor structure with support layer

Info

Publication number: GB2471779A
Application number: GB1011534A
Authority: GB
Inventors: Stuart Leslie Mellor; Philip Aaron
Original assignee: POLYMER RECOVERY Ltd
Current assignee: POLYMER RECOVERY Ltd
Priority date: 2009-07-08
Filing date: 2010-07-08
Publication date: 2011-01-12
Also published as: GB2471687A; GB0911824D0; GB201011534D0

Abstract

A shower floor structure 10 for a shower comprises a moulded plastic top layer 20 which in use has an under surface 26, and a moulded plastic support layer 22. The moulded plastic support layer 22 comprises a base portion 30 defining a base surface (32, Fig 2) and a plurality of support portions 28 disposed over the support layer 22 spaced apart and defining a support surface (36, Fig 2) spaced from the base surface (32, Fig 2). The support layer 22 is bonded to the top layer, in a configuration where either the support surface (36, Fig 2) of the plurality of support portions 28 or base surface (32, Fig 2) of the base portion 30, abuts against and is bonded to the rear surface 26 of the top layer 20 to support the top layer 20 spaced apart from the other of the base portion 30, or support portions 28 support surface (36, Fig 2) of the support layer 22. A base layer 24 is also included in the structure, in an arrangement where the support layer 22 is sandwiched between the base layer 24 and the top layer 20, and the base layer may also be bonded to the support layer 22.

Description

A SHOWER FLOOR STRUCTURE

The present invention relates to a shower floor structure, for example a shower tray or wet room floor former, and in particular to an improved plastic moulded shower tray or wet floor former.

Shower cubicles and wet rooms both require a floor structure with a means of containing and channelling water from the shower to a drain. Shower cubicles typically utilise a tray at the base of the cubicle having raised walls to contain the water, and a sloping floor for channelling water to the drain. Shower trays are typically mounted on the room floor and define a raised shower floor to allow for the drain pipe connection. Wet rooms incorporate a shower unit in a room, or a partitioned section of a room, having a water sealed floor.

Wet room floors, or parts of the floor corresponding to the shower area, are commonly constructed using a pre-formed tray, or wet room former, which is placed beneath the room flooring surface and secured to the timber, concrete or floating floor supports. The wet floor former provides a water proof barrier as well as providing a sloping floor surface defining a run off to a drain. Wet room floor formcrs are generally similar to shower trays except that they typically do not include raised side walls and simply define a sloping floor surface, and are generally disposed flush with the room floor rather than on and above the floor. Providing such preformed shower trays and wet room floor formers saves time and labour costs by avoiding the need to create gradients by hand, and provides a level peripheral floor surface for screens and doors to abut and seal against and to align with the room floor in the case of a wet floor former.

The shower frays and wet floor fonners as well as providing a sloping floor surface must support the combined weight of a user, or users, without flexing or other movement which may fracture watertight seals to the adjoining surfaces or to the plumbing connections. In addition it is also desirable for the shower trays and wet floor formers to be lightweight to make installation easier. Heavy weight products are more likely to be dropped and to suffer surface or other damage, and the recommended maximum safe weight for one person to lift is 25kg.

It is also generally desirable for such shower trays and wet floor formers to be easy to and cheap to manufacture, and increasingly easy to recycle.

Moulded plastic shower trays and wet room formers are known. Such shower frays typically comprise a plastic formed top layer to the underside which is then applied a glass reinforced polyester (GRP) layer, and/or which is back filled with a solid, foamed or composite material, to give additional rigidity and strength. For example, GB2403 143 describes a shower fray back filled with a resin of dicyclopentadienc (DCP) mixed with ground calcium carbonate, with a quantity of methyl ethyl ketone peroxide (MEKP). GB GB23 94413 describes such a shower fray filled with a polymer concrete or resin with the resin or solvent mixed with granulated waste plastic or similar material and poured into a closed and vented mould. A further alternative arrangement is described in EP2025273.

This includes an inner core of solid filler between an outer shell comprising upper and lower moulded plastic sheets. A problem with this, and other prior arrangements, is the resultant weight. For example EP2025273 refers to a conventional tray weighing between 26 and 33kg, which is above the recommend weight one person should lift. EP1956953 describes a fUrther lighter weight shower fray made using an open mould filled with a lightweight resinous material in order to reduce weight. The weight of such solid filled or reinforced products, while less than for example fraditional porcelain shower frays is still however considerable.

Much lighter light weight shower trays and light weight wet floor formers may be manufactured from high density foam with or without an additional polymer resin layer or other reinforcement. However to provide the necessary strength and rigidity these products require an additional exterior grade plywood or similar support of 12 to 20 mm thickness to be placed underneath if they are installed onto floor joists. This adds cost in both labour and materials.

Moulded plastic wet room floor formers are typically made from moulded GRP or similar material to the surface of which is subsequently adhered a slip resistant flooring or floor tiles. Such plastic wet floor formers may be made using a closed mould liquid resin process or resin injection moulding method as for example described in GB2406302 or may be made from a sheet moulded compound reinforced with as for example described in GB240 1341.

The above described conventional products use a variety of materials which make them difficult and expensive or impossible to recycle. GRP is a particular problem. Many of the methods of manufacture also create dust and fumes not conducive to a good working environment. The methods of manufacture or storage of such products can also lead to distortion in the shape of the product creating difficulties in installation.

A self supporting and lighter product with a substantially hollow core may be manufactured by injection moulding. This may involve a single or combination of mouldings. However the disadvantage of this method is the high cost of the injection moulding tooling which is made in steel or aluminium. Wet floor fonners or shower trays are manufactured in a wide range of sizes, so requiring a range of different toohng making is such manufacturing methods uneconomic.

GB2266857, GB2093342EP0643939, and US3606617 all describe generally similar shower tray structures comprising a top facing panel which is bonded or welded to a support layer below, with the support layer having a corrugated structure. These arrangements address some of the problems with the above described arrangements, but as indicated by the later development of the above earlier described alternative structures do not fully address the problems. In particular such arrangements as described in these patents are relatively weak and can be improved.

It is therefore desirable to provide an improved shower tray or wet floor former, and method of manufacturing such a shower tray or wet floor former which addresses the above described requirements and problems and/or which offers improvements or an alternative to existing arrangements.

According to the present invention there is provided a shower floor structure, such as a shower tray or wet floor former as described in the accompanying claims.

In an embodiment of the invention there is provided a shower floor structure, for example a wet floor former or a shower fray, for a shower. The structure comprises a moulded plastic top layer having a rear surface, a moulded plastic support layer comprising a base portion defining a base surface and a plurality of support portions disposed spaced apart over the S support layer and defining a support surface spaced from the base surface, and a base layer.

The support surface of the plurality of support portions or base surface of the base portion abut against, and is bonded to, the rear surface of the top layer to support the top layer spaced apart from the other of the base portion or support surface of the support portions.

The support layer is sandwiched between the base layer and the top layer, and the base layer is bonded to the support layer.

This provides a light weight yet strong and rigid structure potentially capable of supporting a user's weight on the shower floor.

is The plurality of support portions are preferably substantially evenly disposed and spaced apart over the support layer.

The support surface is preferably substantially parallel to and spaced from the base surface.

Preferably the support portions comprise raised portions of the moulded plastic support layer. The raised portions forming at least one of the support portions may have a circular, square or other geometric shape. At least one of the plurality of support portions may comprise an elongate rib. At least one of the plurality of support portions may comprise a peripheral support portion around a periphery of the support layer.

The support portions preferably comprise a planar support surface portion defining the support surface and a support wall extending from and interconnecting the support surface portion with the base portion to support the support surface portion from the base portion.

The support wall is preferably substantially perpendicular to the support surface portion and the support surface.

The support layer may be moulded from a plastic sheet. Preferably the support layer and top layer are made from the same plastic material. The support layer and/or top layer may be for example made from any polymer / polymer resin such as ABS, polyethylene sheet, polypropylene sheet, styrene or other similar materials. The support layer is preferably vacuum moulded.

The base layer may include a plurality of location features engaging support layer to locate the support layer with respect to the base layer.

The base layer may comprise a peripheral edge wall around periphery of the base layer.

The top layer may include a peripheral edge wall projecting from rear surface of the top layer and around a periphery of the top layer. The support layer may include a peripheral edge wall around the periphery of the support layer. The peripheral edge walls of the top layer and/or support layer and/or base layer may abut and may be bonded together.

The top layer preferably has a sloped top surface sloping from a peripheral edge of the top layer for channelling water.

The structure may further comprise a gully drain for receivipg water.

More generally in accordance with an aspect of the invention a wet floor former or shower tray, comprises two or more fonned or moulded layers bonded together. One layer is a substantially hollow formed or moulded support layer or core which is bonded to a top layer to increase strength and rigidity. Further layers, may be added to provide additional strength, features and benefits.

The invention addresses the disadvantages of the above methods by the use of 3 or more layers of sheet materials. These can be formed using tooling which is relatively inexpensive and lends itself to small volume production of a given product size.

The principal advantages of our invention are its lightweight and strength as compared to other conventional structures. For a given size a product manufactured according to the invention will weigh between 9 and 16kg compared to 24 to 40kg for conventional products while still having the required strength and rigidity. The product is also not prone to warp or distort in manufacture or storage. In addition it is also relatively economic to manufacture. Manufacture or trimming during installation does not create dust or harmful fumes.

Advantageously the structure is manufactured from a single type of material in order to assist recycling at the end of its service life. Preferably the sheet or moulding material from which the structure is made can itself be material which has already been recycled, such as ABS (Acrylonitrile Butadiene Styrene).

The present invention will now be described by way of example only with reference to the following illustrative figures in which: Figure 1 is an exploded schematic perspective illustration of a shower floor structure in accordance with an embodiment of the present invention; Figure 2 is a schematic cross sectional view of part of the assembled shower floor structure of Figure 1 along section A-A; Figure 3 is an exploded cross sectional view of base layer of the shower floor structure shown in Figure 1 with a waste trap; Figures 4, 5 and 6 are schematic cross sectional views similar to that of figure 2 but showing alternate embodiments of the shower floor structure; Figures 7, 8 and 9 are exploded schematic perspective illustrations of shower floor structure in accordance with further alternate embodiments of the present invention; Figure 10 is a plan view of an alternate support layer similar to that shown in figure 9 but with an alternative pattern of support portions; Figure 11 is an exploded schematic perspective illustration of a shower floor structure in accordance with another embodiment of the present invention; Figure 12 is a plan view of the support layer shown in figure 11; Figure l3a is a cross sectional view through the assembled show floor structure showninfigurell;and Figure 1 3b is a more detailed part view of the cross section shown in figure 1 3b.

Referring to Figures 1 to 3 there is shown a shower floor structure, and more specifically a wet room floor former 10 in accordance with an embodiment of the invention. The wet room floor former 10, as is known in the art, is a prefabricated structure having a slopping upper surface 12 which is used to form the floor of the wet room, or at least an area of the wet room corresponding to the shower area, and upon which a user stands when using the shower. The wet room floor former 10 is secured to the room floor, and in particular to timber, concrete or floating floor sections of the wet room floor with the upper surface 12 of the wet room floor former 10 generally flush with the surrounding room floor surface.

The slopping surface 12 may form the floor surface of the wet room in the region of the shower area, or more typically is covered with a fbrther waterproof covering, or tiled, with the remainder of the wet room floor. The slopping upper surface 12 acts to channel water from the shower towards a drain gully 14 which is then connected to the drainage and sewerage system. The upper surface 12 of the wet room floor fonner 10 typically also includes a peripheral edge 16 which is flat and substantially horizontal, in contrast to the slopping main section of the upper surface 12. This flat peripheral region 16 is aligned with the remainder of the room floor to form a flush surface between the floor and upper surface 12 of the wet room floor former, and upon which various enclosure structures may abut and seal against.

Whilst the particular embodiments of the invention described and shown relate to a wet room floor former 10, the invention can also be applied and used to form other similar prefabricated shower floor structures, and in particular to form a shower tray. A shower tray is generally similar to a wet room floor former having an upper surface which forms a floor upon which a user stands with the upper surface and floor generally slopping towards a drain gully. A shower tray is however usually mounted above the room floor surface in a slightly elevated position, and ftirtheimore generally also includes a peripheral upturned surround rim (upstand) around the periphery of the shower tray to better collect and retain water from the shower within the shower tray and upon which shower enclosure screens may rest and be abutted.

In accordance with the invention, the wet room floor former 10 comprises a moulded plastic top layer 20, a moulded plastic support layer 22, and a further moulded plastic base layer 24. The layers 20, 22, 24 form a laminate structure forming the wet room floor former 10, with the support layer 22 being sandwiched between the top layer 20 and base layer 24.

The moulded plastic top layer 20 defines the upper sloping surface 12 and a peripheral rim surface 16 and has an opposed rear surface 26. The top layer 20 comprises a relatively thin, typical 2mm to 5mm thick moulded laminar sheet.

The support layer 22 also comprises a relatively thin, typically 2mm to 5mm thickness moulded laminar sheet, which is moulded and formed and shaped so as to have a plurality of raised support portions 28 disposed over the support layer 22. The support portions 28 project from a lower base portion 30 of the support layer 22 extending between the support portions 28, with the base portion defining a rear base surface 32 of the support layer 22.

The raised support portions 28 preferably comprise raised portions projecting from the base portion 30 of the support layer 32. The plurality of support portions 28 each comprise a circular planar support surface portion 34 defining a support surface 36 which is generally parallel to the base portion 30 and base surface 32. The support surface 36 in fact is preferably at a slight angle corresponding to the slope and sloped upper surface 12 of the top layer 20. The support surface portion 34 and surface 26 are spaced from the base portion 30 a vertical distance h by an essentially vertical, or in an alternative embodiments semi-vertical, support waIl 38 around the periphery of the support surface portion 34. The support surface portions 34 and plurality of support surfaces 36 defined by them are generally circular in their embodiment as shown in Figure 1. In other embodiments, they may be of any shape, for example square or hexagonal. In addition or alternatively one or more or all of the raised support portions 28 may comprise linear straight or curved rib sections 100, 102 as for example shown in Figures 7 and 8. Around the periphery of the support layer 22 there is a further peripheral support portion 40 for defining a peripheral support surface 42 which is coplanar with the support surfaces 36 of the other support portions 28, and is similarly supported by vertical support walls 44 from the base portion 30. As shown in Figure 2 the support surfaces 36 and 42 of the raised support portions 28 and peripheral support portions 40 abut against the rear surface 26 of the top layer 20 and are bonded to the top layer 20 by heat bonding or adhesive.

The base layer 24 similarly comprises a relatively thin, typically 2mm to 5mm thickness moulded laminar sheet and has an upper base surface 38 which abuts against and is also preferably bonded to the rear base surface 32 of the support layer 22 by either heat bonding or adhesive. The base layer 24 covers the rear of the support layer 22, and in particular closes off the underside of the support portions 28 and provides an essentially flat and continuous rear surface 52 of the wet room floor former 10.

The base layer 24 may fhrther comprise a plurality of location features 50 projecting from the upper base section 38 which correspond to and are shaped to fit within the rear underside of the support portions 28 of the support layer to thereby locate the support layer 22 on the base layer 24. These location features 50 preferably comprise smaller moulded raised portions or indentations of the base layer 24 which as shown in Figure 2 do not completely fill the under side of the raised portions 28. Alternatively there may comprise suitably thickened portions of the base layer 24 although this is less preferable since it increases the material and weight of the base layer and is more difficult to form. The location features 50 and indentations may also define a recessed rear surface 52 of the base layer 24 to assist in bonding the base layer 24 and wet room floor former 10 to the floor and/or turning into a concrete base. Alternatively other surface roughening features may be provided on the rear surface 52 to assist in such beading in.

In other variations the bonding of base layer 24 to the support layer 22 provides significantly,more strength and rigidity to the structure than simply abutting the base layer against the support layer 22. The location features 50 and interlocking of the base layer 24 with the support layer 22 provides further interengagement and interconnection between the layers 22,24.

As assembled, and as shown in Figure 2, the support layer 22 is sandwiched between the top layer 20 and base layer 24. The support layer 22 and specifically the raised support portions 28 and vertical support walls 38 space and support the top layer 20 spaced from the base layer 24 by vertical distance h. The laminate construction and in particular bonding of the support layer 22 to the top layer 20, as well as the shaping of the support layer 22, and having the further base layer 24 bonded to the support layer, strengthens and provides rigidity to the various layers and to the overall wet room floor former 10. In particular such a laminate structure is much stiffer and rigid than a single layer and the shaping significantly increases the rigidity of the support layer 22. More specifically the bonding of the support surfaces 36, 42 and of the base surface 42 to the upper surface 48 of the base layer 34 prevent lateral movement of the vertical or semi-vertical support walls 38 when weight and loading is applied to the upper surface 12. In addition under such vertical loading, the embodiment also puts the base layer 24 under tension which greatly improves the rigidity and torsion of properties of the combined structure. The bonding of the top layer 22 to the support layer 22, and bonding of the support layer 22 to the base layer 24, as well as limiting movement between these layers also puts more uniform surface pressure on to the semi and vertical walls of the support layer 22 and similarly places it under tension. The support surface portion 34 of the support portion 28 and base surface 30 portion of the support layer 32 also selectively thickens the top layer 20 and base layer 24 strengthening these layers and the overall structure.

In addition spaces and cavities 54, 56, 72 are defined between the top 20 and support 22 layers and between the support layer 22 and base layer 24. The cavities 54, 56, 72 are preferably sealed to prevent ingress of water and provides additional structural strength by virtue of the air volume sealed within the cavity 54, 56. This also makes the structure relatively light weight. In particular a wet room floor former 10 manufactured in accordance with the invention may weigh between 9Kg and 16Kg as compared to a similar size conventional product which nay weigh between 24Kg to 40Kg.

The top layer 20, support layer 22 and base layer 24 are all preferably formed from laminar sheet material typically of between 2mm and 5mm thickness moulded by for example preferably vacuum moulding, but also alternatively thermal moulding or cold pressure moulding, into the respective shapes and profiles and in particular to form both the slopping upper surface 12 of the top layer 20 and raised portions 28 of the support layer 22.

Such moulding of sheet material is a relatively cheap manufacturing process with the respective layers 20, 22 and 24 being preformed and them bonded together to form the wet room floor former 10. One or more of the layers may alternatively be formed by different moulding process, for example pressure or injection, rotational or blow moulding.

It is preferable that all of the layers are formed from the same plastic material in order to enable easy recycling. The top layer 20, support layer 22 and base layer 24 are preferably formed from recycled plastic material and will most preferably be formed by ABS (Acrylonitrile Butadiene Styrene). Alternatively any other plastic material or polymer resin material could be used for any or all of the layers 20, 22, 24. Such materials are relatively wide spread and cheap. Furthermore moulding and trimming during manufacture and/or installation of such material does not create harmful dust or fumes. Alternatively in other embodiments one or more of the layers may be fonned from a different material, and in particular the top layer 20 may be formed from GRP to provide similar additional strength and reinforcement.

The raised support portions 28 of the support layer 22 are evenly distributed over the support layer 22 to provide an even support for the top layer 20. In particular it is important to provide adequate support and reduce the risk of bowing of the top layer 20 that the support portion 28, and in particular support surface portion 34 of the support portion 28, as well as the spacings between the raised portions 28, are relatively small. More specifically it is important that the spacing between the support portions 28 and sizing of the support portions 28 is less than the area of any likely point load pressure point to which the upper surface pressure 12 of the wet room floor former is likely to experience. In particular in the regions between the raised support portion 28 the wet room floor former has a single thickness corresponding to the thickness of the top layer 20 whereas in the regions of the raised support portions 28 there is a double thickness corresponding to the thickness of the top layer 20 and support portion 34 of the support layer 22. Such point loading may correspond to one or more heavy users standing in the shower, but in addition may also be due to the legs and feet of a shower stool or seat sometimes used within the shower with such a shower seat leg having a foot of typically 30mm diameter. Accordingly the spacings between the raised portions should correspond to the diameter and so not more than 30 millimetres. Tests of a wet form former 10 made in accordance with the invention, and as described above and shown in figure 1 to 3 with bonded top 20, support 22 and base layer 24, have indicated that it can support a loading in excess of 260Kg, and point loadings for example a shower stool or similar objects of 130Kg.

The peripheral edge of the top layer 20 further comprises a peripheral edge wall flange 60 extending rearwardly and generally perpendicular to the upper surface 12 and around the entire periphery of the top layer 20. The support layer 22 may also further comprises a generally vertical peripheral edge wall 62 both surrounding substantially all of the periphery of the support wall 22 and extending perpendicularly to the support surface 36, 42 and base surface 32. Similarly the base layer 24 may include an upstanding peripheral

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edge wall flange 64 in this case extending upwardly of the base surface 32. These peripheral edge flanges project generally away from the remainder of the layers 20, 22 and 24 and around the entire periphery and improve the rigidity of the individual layers. In addition and as shown in Figure 2 these peripheral edge walls 60, 62, 64 are abutted and are also bonded together by suitable adhesive and/or hot bonds to provide structural strength to the wet room floor former 10. The flanges 60, 62, 64 also support and space apart the layers 20, 22, 24 with distal ends of the edge walls corresponding layers. The peripheral edge walls 60, 62, 64 also provide a thickened outer edge of the wet room floor former 10 providing further strength around the periphery. In addition this thickened edge region has a lateral solid thickness 66 which allows screws to also be inserted vertically for example to secure wall panels into the structure.

While preferably the peripheral edge flange walls 60, 62, 64 are perpendicular to the layers 20, 22, 24, it will be appreciated that they can be at any angle to the layers 20, 22, 24. In other embodiments, one or more the peripheral edge walls 60, 62, 64 may also be spaced apart for each with the other to define a void 68 therebetween into which for example flooring material 70 may be inserted as shown in Figure 6. Alternatively one or more or all of the layers may omit such a peripheral edge flange wall 60, 62, 64.

To provide further structural strength for example around the edge of the wet room floor former 10, a solid timber beam or other material (not shown) preferably joined by adhesive or other fastening to the former 10 may be provided around the peripheral edges, and in particular within the peripheral cavity 72 between the peripheral support portion 40 of the support layer 22. This may also increase the width of the material around the edges for fixing screws. Such a beam in particular may be used to provide strength and rigidity if the layers 20,22,24 omit peripheral edge flanges 60, 62, 64.

The top sheet 20 also includes a shaped and moulded gully 14, in this case located centrally within the top layer 20 and into which the top surface as of the top layer 20 slopes to direct and channel water. The gully 14 comprises a moulded dish shaped portion of the top layer 20. Similar dish shaped portions 75, 76 may also be formed in the support layer 22 and base layer 24 to accommodate and define this central gully 14. The layers 20,22,24 also include a through aperture 78a, 78b, 78e into which a drainage pipe for the water may be fitted, an into which a trap 80 for connection to the drainer or sewerage system can be connected to carry away the water from the shower. In the preferred embodiment, the top layer 20 may also include a cylindrical extension (not shown) projecting downwardly from the top layer 20 surrounding the aperture 78a which then passes through the subsequent layers for direct connection to the fray adaptor 80. The gully 14 while preferably and typically located in the centre may alternatively be located to one side or end, or even omitted entirely and provided separately.

The upper surface 12 typically has a slope and fall of not less than 1:40 from the peripheral edge region 16 to the gully 14 in order to adequately channel and direct water. It should be noted that this sloping profile required dictates that the wet room floor former 10 must have a sufficient thickness and depth to accommodate the profile of the upper surface and accordingly set a minimum height h for spacing apart the layers 20, 22, 24.

As shown in Figures 4 and 5 the upper surface 12 of the top layer 20 may also include a non-slip film adhered to the upper surface or alternatively additional surface texture features 84 attached or moulded into the upper surface 12 of the top layer 20.

Figures 7, 8 and 9 show further alternative embodiments of the invention which are generally similar to that shown in Figures 1 to 3 and like reference numerals used for like features, and only the differences will now be described. In Figures 7, 8 and 9 the base layer 24 also does not include any location features 50 and comprises a flat sheet material bonded to the support layer 22. In Figure 7 the support layer 22 also includes generally linear support ribs 100 moulded into the support layer 22 similarly to the remaining support portions 28. These ribs 100 provide further structural rigidity and also prevent warping and twisting of the support layer 22 and so also of the wet room floor former 10.

In Figure 8 the support layer 22 includes generally circular ribs 102. The pattern and distribution of the support portions 28 in Figure 8 is also different. In this ease the support portions are arranged in a circular pattern within and between the circular ribs 102.

Another alternative support layer and pattern of support portions 28 is shown in Figure 9, in which the base layer 24 has been omitted.

It has been found and identified that the pattern and arrangement of the support portions 28 of the support layer 22 is important to the strength of the structure 10. In particular it has been identified that if the support portions 28 are aligned, as for example shown in figures 1 and 9, or arranged more generally in a regular pattern that straight lines are can be established between the support portions 28 and linking the support portions 28 extending across the structure 10. For example in the arrangement shown in figure land 9 the support portions 28 are aligned along lines extending parallel to both the long and shorter sides, and in addition extending on diagonally across the support layer 22. Such straight lines and alignment of and between the support portions 28 it has been found give rise to a weakness in the support layer 22 and so structure 10, with the structure under loading tending to fold along such straight lines.

This can be addressed to some degree by providing ribs, and in particular diagonal ribs 100, as for example shown in figure 7. The ribs 100 break up such lines of weakness and alignment between the support portions 28 and stiffen the structure. However as can be seen in figure 7, lines of weakness along which the structure could bend and fold still exist parallel to the ribs 100.

To further address this problem the support portions 28 can be arranged in a circular pattern and/or circular ribs 102 can be provided. While the support portions 28 and ribs 102 are still in such cases aligned, since they are aligned along a curved lines rather than straight lines this does not represent a line of weakness along which the structure could fold under load. As such the stiffness of the support layer 22 and so structure 10 is not compromised by such curved alignments. Care has however to be taken when arranging the support portions 28 in a circular configuration to avoid accidental alignment of the support portions 28 along straight radial lines, and the circular arrangement of the support portions 28 should be cireumferentially staggered. Alternatively or additionally circular ribs 102 as shown can be provided to break up such radial alignment.

Another way to address this problem of linear alignment of the support portions 28 is to arrange them in a random, or at least semi random, configuration where they are not aligned. Such an arrangement is shown in figure 10. Such a random pattern, or pseudo random pattern is however difficulty to achieve and can lead to problems when producing structures of different sizes.

Another alternative embodiment which addresses this problem is shown in figures 11 to 13. This embodiment and structure 10 is similar to that shown in figure 1, and like reference numerals are used for the like features, and only the main differences will be described in detail.

In this arrangement the support portions 28 are based upon hexagonal shaped support portion elements 28a,28b,28c arranged in an aligned regular pattern. However in order to break up the alignment, the basic hexagonal support structure elements 28a,28b,28c are joined together and linked to form a composite support portions 31. In this case three adjacent hexagonal elements 28a,28b,28c are linked by two bridging section elements 29a, 29b structures in a V configuration. Moreover such linked V shaped support portions 31 are then arranged in a staggered pattern with some in an orthogonal and minored dispositions in order to place the bridge portions 29a,29b across and breaking up any straight alignment lines across the support layer 22 which may give rise to weaknesses. As shown to complete the structure individual hexagonal support portions 28e and double support elements 33 formed from pairs of hexagonal support elements 28a,28b linked by a single bridge portions 29c may also be incorporated. In essence the bridge portions 29a,29b, 29c cross and break up any straight alignment lines extending significantly across the support layer 22.

This arrangement is akin to a honeycomb structure which has been opened up with the cells spaced apart such that it can be formed from vacuum moulding and bridge portions then being provided between the cells to break up any straight liens of weakness and alignment between the cells.

This arranged has been found to be particularly strong and rigid.

In the arrangement shown in figure it the location features 50 are only provided around the periphery of the base layer 24 simplifying the base layer 24 structure.

In this embodiment, and as shown in more detail in figures 13a and 13b, the peripheral flanges 60,62,64 of the top layer 20, support layer 22 and base layer 24 are differently disposed to that shown in figures2 and 4 to 6. In particular the upstanding peripheral flange 64 of the base layer 24 is interposed between the downwardly extending peripheral flanges 60,62 of the top and support layers 20,22. As a result the base layer 24 extends over and covers the distal edge of the support layer flange 62 and the interface between the support layer 22 peripheral flange 62 and base layer 24 peripheral flange 64. This is advantageous since it prevents water and moisture ingress at this interface and between the base layer flange 64 and support layer flange 62 which can lead to problems, and if the flanges 64,62 are joined could lead to delimitation of such a joint between the layers 24,22.

It will be appreciated that while the flanges 60,62,64 are shown in figure 13 and being spaced from each other in a preferred embodiment the flanges 60,62,64 abut and are bonded together.

Other embodiments may also include further additional layers, preferably bonded to the other layers to provide additional strength and rigidity, although increasing complexity and weight. In particular an additional similar moulded support layer similar to the first support layer 22 could be bonded to the base layer 24 sandwiched there between. The additional support layer could be staggered or inverted with respect to the first support layer such that the support portions 28 are not aligned, or the further support layer and support portions could be aligned.

While in the embodiments shown the support portions 28 project generally upward from the base surface and portion of the support layer, it is appreciated that this arrangement can be reversed and the support layer 32 inverted such that the base portion 30 abuts against and is responded to the rear surface 26 of the top layer 20 and the support portions 28 and support surface 36 abuts against the base layer 24.

Also while the invention has been described in relation to a wet room floor former 10, as mentioned above, the invention can also equally be applied to a shower tray. In such case the top layer 20 may the include an upstand peripheral edge wall and surround (upstanding) around its periphery or at least around one or more sides to define a water tight rim around the upper edge of the shower tray and upper surface 12. Alternatively a peripheral edge region similar to region 16 of the wet room floor former 10 may be provided but elevated and spaced above the remainder of the slopping surface 12 such that the peripheral edge region 16 defines the upstand of the shower tray.

It will be appreciated that in further embodiments various further modifications and variations to the specific arrangements described above and shown in the drawings may be made. For example the layers 20,22,24 can be formed or moulded to create different tray styles i.e. level access, ramped, shallow or deep upstands, access for plumbing etc.

Claims

CLAIMSI. A shower floor structure for a shower comprises a moulded plastic top layer having a rear surface, and a moulded plastic support layer comprising a base portion s defining a base surface and a plurality of support portions disposed spaced apart over the support layer and defining a support surface spaced from the base surface, and a base layer; wherein the support surface of the plurality of support portions or base surface of the base portion abuts against and is bonded to the rear surface of the top layer to support the top layer spaced apart from the other of the base portion or support portions support surface of the support layer; and wherein the support layer is sandwiched between the base layer and the top layer, and the base layer is bonded to the support layer.
2. A structure as claimed in claim I wherein the base layer comprises a plurality of location features engaging support layer to locate the support layer with respect to the base layer.
3. A structure as claimed in claim I or 2 wherein the base layer further comprises a peripheral edge wall around periphery of the base layer.
4. A structure as claimed in any preceding claim wherein the top layer further comprises a peripheral edge wall projecting from rear surface of the top layer and around a periphery of the top layer.
5. A structure as claimed in any preceding claim wherein the support layer further comprises a peripheral edge wall around the periphery of the support layer.
6. A structure as claimed in any of claims 3 to 5 wherein the peripheral edge waIls of the top layer and/or support layer and/or base layer abut and are bonded together.
7. A structure as claimed in any preceding claim wherein the top layer has a sloped top surface sloping from a peripheral edge of the top layer for channelling water.
8. A structure as claimed in any preceding claim wherein the plurality of support portions are substantially evenly disposed and spaced apart over support layer.
9. A structure as claimed in any preceding claim wherein the support surface is substantially parallel to and spaced from the base surface.
10. A structure as claimed in any preceding claim wherein the support portions comprise raised portions of the moulded plastic support layer.
Ii. A structure as claimed in claim 10 wherein raised portions forming at least one of the support portions have a circular, square, hexagonal or other geometric shape.
12. A structure as claimed in any preceding claim wherein the support portions are staggered over the support layer such that they do not align along a straight line across the support layer.
13. A structure as claimed in any preceding claim wherein at least some of the plurality of support portions are arranged in a random or semi random pattern over the support layer.
14. A structure as claimed in any preceding claim wherein at least some of the plurality of support portions comprise support elements that are connected together by bridging portions to form composite support portions.
15. A structure as claimed in claim 14 wherein the composite support elements are arranged in a V or U shaped configuration.
16. A structure as claimed in claim 15 wherein the composite support elements are disposed different orientations and/or staggered over the support layer.
17. A structure as claimed in any preceding claim wherein at least one of the plurality of support portions comprises an elongate rib.
18. A structure as claimed in any preceding claim wherein at least one of the plurality of support portions comprises a peripheral support portion around a periphery of the support layer.
19. A structure as claimed in any preceding claim wherein the support portions comprise a planar support surface portion defining the support surface and a support wall extending from and interconnecting the support surface portion with the base portion to support the support surface portion from the base portion.
20. A structure as claimed in claim 17 wherein the support wall is substantially perpendicular to the support surface portion and the support surface.
21. A structure as claimed in any preceding claim wherein the support layer is moulded from a plastic sheet.
22. A structure as claimed in any preceding claim wherein the support layer and top layer are made from the same plastic material.
23. A structure as claimed in any preceding claim wherein the support layer and/or top layer are made from polymer resin, for example ABS.
24. A structure as claimed in any preceding claim wherein the support layer is vacuum moulded.
25. A structure as claimed in any preceding claim further comprising a gully drain for receiving water.
26. A structure as claimed in any preceding claim comprising a wet floor former, or a shower tray.
27. A structure substantially as hereinbefore described with reference to, and/or as shown in any one or more of figures Ito 13b.