GB2598811A

GB2598811A - Building tray and method of construction

Info

Publication number: GB2598811A
Application number: GB2105189.1A
Authority: GB
Inventors: Pulcini Stefano
Original assignee: ACS Stainless Steel Fixings Ltd
Current assignee: ACS Stainless Steel Fixings Ltd
Priority date: 2020-08-17
Filing date: 2021-04-12
Publication date: 2022-03-16
Anticipated expiration: 2041-04-12
Also published as: GB202105189D0; GB2598811B

Abstract

A method for producing a three-dimensional corner from a sheet, comprising the steps of providing the sheet of material with an X-Y plane, determining a first line along the X axis of the X-Y plane of the sheet of material, and determining a second line along the Y axis of the X-Y plane of the sheet of material. The first line and the second line are arranged such that they intersect and form a square in a corner of the sheet of material. The method further comprising bending the square in the corner of the sheet along the diagonal of the square formed that ends in the apex of the sheet of material, bending the sheet of material along the first line and rotating the material between the first line and the edge of the sheet of material, bending the sheet of material along the second line and rotating the material between the second line and the edge of the sheet material such that the square in the corner of the sheet of material is bent in half into a triangle and positioned outside of three dimensional corner created in the material, and bending the triangle to attach it to one side of the corner of the three dimensional corner. Such a corner may be formed at each corner of a rectangular sheet to form a tray for use as a wall cavity tray.

Description

Building Tray and Method of Construction The present application relates to a method of manufacturing a tray. The tray may be used as a cavity tray, or as a fire barrier amongst other applications. In particular, the tray is made without the use of welding, or by minimising the amount of welding required in manufacture.

A common building construction is that of a main structure which is produced using the latest building technology and materials, surrounded on the outside by a cladding, perhaps made of more traditional materials like bricks. The benefits of this structure are that the main building can be built from any number of new materials and therefore fulfil all building regulations as these develop, while the cladding forms an outer wall that can be made more aesthetically pleasing. Such a structure typically includes a cavity between the main building and the cladding, wherein this cavity not only increases insulation of the building from the external elements and environment, but also allows greater flexibility when constructing the main building structure.

As will be appreciated, it is possible that water, vapour and any other liquids, may permeate into the cavity structure, and form droplets which will, under the act of gravity, drop down the interior of the cavity. Additionally, the interior sides of the walls making up the cavity wall also provide a condensation point for water, or other liquids, which will also mean that droplets and moisture will run down the sides of the interior of the cavity wall. It will be appreciated that water gathering at the bottom of the cavity wall can lead to damage to both walls making up the cavity wall, and in particular to the wall making up the main structure. It is further noted that many building materials, especially bricks, are permeable and will soak up and store water if this is not satisfactorily removed. Such issues are undesirable, as they shorten the lifetime of the structure or lead to undesirable and unwanted repairs falling due.

Systems are known for attracting and guiding the moisture which arises in the cavity wall. However increased safety in building regulations and the like, requires that all building materials conform to high standards in fire prevention and that they minimise the possible spread of any fire. The present disclosure presents a cavity tray for use in a system of water guidance for collecting and channelling water existing within the cavity wall, whilst also ensuring appropriate conformity with building regulations, in particular the requirement of low flammability to the structure. Whilst some such trays have previously been described they have been manufactured using a welded construction. Such a welded construction has many disadvantages including the welds being a point of weakness and therefore prone to failure from corrosion due to the liquids themselves, or from high temperatures in the case of fire.

Moreover, as is known from the Grenfell Tower disaster (14 June 2017, UK) it is imperative that buildings such as high rise buildings, and especially those clad with materials have adequate fire safety. As such fire barriers are required to ensure that the spread of fire is slowed. One form of fire barrier or fire sock comprises a cast-in metal plate that is mortared into the inner and outer masonry skins of a cavity wall so that it bridges the cavity. The plate is again designed to form a barrier preventing the spread of smoke and flames. The problem with such simple metal barriers is that they are awkward to fit. Typically, the inner skin of a cavity wall comprises blockwork whereas the outer skin comprises bricks. This means that the mortar courses in the brick skin and the blockwork skin may not line up horizontally, making it difficult to fit the plates where they are required. Also, the plates have to be cut to fit over and around masonry supports, which compromises their effectiveness, so that gaps between the masonry supports and the plates have to be filled with an appropriate filler, which again adds to the construction time and can lead to such gaps being left open.

Welded materials in fire barriers may present weaknesses at high temperatures. Moreover, the use of a welded material means that the thickness of the fire barrier must be a set thickness (for example, around 2-4mm depending on the metal, and the type of join etc.) for the weld to be of sufficient strength. This minimum thickness places limitations on where fire barriers may be positioned within a building. Thicker fire barriers also increase cost and are less environmentally friendly. One object of the present invention is to provide a fire barrier for use in a cavity wall that overcomes the aforementioned disadvantages of conventional barriers.

A further object of the present invention is to provide a method of manufacturing structures without the use of welding. These structures may for example be used in the construction industry, or other industries, where strength is important.

According to a first aspect of the present invention there is provided a method of producing a three-dimensional corner from a sheet material as recited in the claims.

According to a second aspect of the present invention there is provided a cavity tray formed using the claimed method of manufacture.

According to a third aspect of the present invention there is provided a cavity tray system comprising the claimed cavity tray.

According to a fourth aspect of the present invention there is provided a fire barrier formed using the claimed method of manufacture.

According to a fifth aspect of the present invention there is provided a building comprising one or both of the fire barrier or cavity tray as claimed.

Examples of the present invention will now be described with reference to the accompanying drawings.

DESCRIPTION OF THE FIGURES

Fig 1: A planar sheet of material shown from above.

Fig 2: The planar sheet of Figure 1 show with first and second lines shown from above.

Fig 3: The planar sheet of Figure 2 with a bend shown in the diagonal of the square created in the corner of the planar sheet.

Fig 4: The sheet of Figure 3, wherein the first lip has been rotated relative to the remainder of the planar sheet, shown in a perspective view.

Fig 5: The sheet of Figure 4, wherein the second lip has been rotated relative to the remainder of the planar sheet, shown in a perspective view.

Fig 6: The sheet of Figure 5, wherein the triangle created outside of the three-dimensional corner is rotated to conjoin with the three dimensional corner, shown from above.

Fig 7: A completed three-dimensional corner is shown in a perspective view.

Fig 8: A planar sheet with an indentation is shown from above.

Fig 9: A perspective view of a first embodiment of a fire barrier constructed in accordance with the present invention; Fig 10: A side view of the fire barrier shown in Fig, 8 but to an enlarged scale; and Figs 11 and 12: Views similar to Figs. 9 and 10 but of a second embodiment of fire barrier in accordance with the present invention.

Fig 13: Cross-sectional view of a cavity wall showing a wall cavity tray system in accordance with the present invention.

Fig 14: Perspective view of the outer wall of a cavity wall showing the cavity tray system according to Fig. 13.

Fig 15: Perspective view of one example of the cavity tray system.

Fig 16: Perspective view of another example of the cavity tray system without a fixing structure to the wall.

Fig 17a: Mechanical joint with further drainage channels at joint.

Fig 17b: Cross-section of tray showing drainage channels at joint.

Fig 17c: Mechanical joint of Fig. 17a with cap holding trays in alignment.

Figure 1 shows a sheet of material 31. In Figure 1 this material is shown as being planar. Figure 1 also shows the sheet of material as being rectangular. The long side is referred to as the first side. The short side is referred to as the second side. In the event the sheet of material is square these names may be used interchangeably. The sheet of material has a thickness (not shown). In some advantageous embodiments the thickness is 0.5mm. At present the UK Guidelines only allow a minimum thickness of 0.5mm, however this technique may allow for thinner barriers to be used in the future subject to appropriate legislation. For example, thicknesses between 0.3mm and 2.0 mm may be used. More preferably a range of thickness between 0.5mm and 2.0mm may be used, and more preferable a range of thickness between 0.5mm and 1.5mm may be used. Thicknesses around 2mm are harder to bend and therefore may be harder or less economical to produce.

Figure 2 shows the sheet of material 31 of Figure 1. A first line 37 has been determined along the X axis of the sheet of material 31. This first line 37 runs parallel with the first side of the sheet of material 31. The first lip 33 comprises the material between the first line 37 and the first side of the sheet of material. A second line 36 has been determined along the Y axis the sheet of material 31. The second line 36 runs parallel with the second side of the sheet of material 31. The second lip 34 comprises the material between the second line 36 and the second side of the sheet of material 31. The first 37 and second 36 lines have been determined such that they intersect and form a square 35 in the corner of the sheet of material 31. This square is shown in Figure 2. These lines may be marked physically onto the sheet of material 31. Alternatively, they may simply be determined. They may be recorded remotely from the sheet of material, for example in the memory of a computational device.

Figure 3 shows the sheet of material 31 of Figure 2. The diagonal line 38 of the square in the corner 35 of the sheet 31 that ends at the apex of the sheet of material is also shown. The square 35 in the corner of the sheet of material is bent along the diagonal line 38 shown. This bending may take place in any number of ways. For example, a sheet metal bending machine may be used to produce a bend along the diagonal 38. It is noted that in some embodiments this may cause the square 35 in the corner of the sheet to stretch or deform, however this may also be avoided. Other bending techniques may include scoring the sheet of material 31 along the diagonal 38, or stamping the diagonal 38 of the square 35 with a longitudinal stamp with sufficient force to cause an indentation to form along the diagonal 38, but not sufficient force to pierce the sheet of material.

Figure 4 shows the sheet of material 31 being bent along the first line 37. The first lip 33 is rotated relative to the remainder of the sheet of material 31. This is shown as being rotated such that it forms a first wall approximately perpendicular to the remainder of the sheet of material 31. This rotation may be achieved by first bending the sheet of material 31 along the first line 37. This bending may be achieved by using a sheet metal bending machine. Alternatively, the first line 37 may be scored or stamped. Other suitable techniques may also be used. The rotation may be performed using a bending press or other suitable equipment/techniques.

Figure 5 shows the sheet of material 31 being bent along the second line 36. The second lip 34 is rotated 40 relative to the remainder of the sheet of material. This is shown as being rotated such that it forms a second wall approximately perpendicular the remainder of the sheet of material 31, and approximately perpendicular the first wall 33. It is noted that during this rotation the material that previously formed the square in the corner of the sheet of material folds in on itself along the bend in the diagonal line. This creates a triangular element 41. The first wall 33 and the second wall 34 together with the remainder of the sheet of material (which forms a base 32) partially enclose a volume. The triangular element 41 is positioned outside of this enclosed volume. This rotation may be achieved by first bending the sheet of material 31 along the second line 36. This bending may be achieved by using a sheet metal bending machine. Alternatively, the second line 36 may be scored or stamped. Other suitable techniques may also be used. The rotation may be performed using a bending press or other suitable equipment/techniques.

Figure 6 shows the triangular element 41 being bent so as to be positioned directly adjacent the first wall 33. It is noted that the triangular element 41 may be bent so that it is positioned directly adjacent either the first 33 or the second 34 wall.

This may be performed using a bending press, a manual folding tool, or some form of hand tooling, or any other suitable apparatus or technique.

Figure 7 shows a perspective view of the completed three-dimensional corner once the triangular element 41 has been positioned directly adjacent the first wall 33. This may be the end of the manufacturing process. Optionally the triangular element 41 may be bonded to the first wall 33 by means of an adhesive, or by any other means.

It is noted that the method shown and described with reference to Figures 1-7 may be used to create more than one three-dimensional corner from a sheet of material 31. For example, one, two, three, or four corners may be produced (or even more if the sheet of material has more sides to begin with). For each corner that is required a square in the desired corner must be determined by determining first and second lines parallel to the two sides forming the desired corner. The diagonal in the corner must then be bent. Therefore, where a tray with four corners is desired first, second, third and fourth lines are determined to form first, second, third, and fourth corner squares. Each diagonal of each square is then bent before the first, second, third and fourth sides are rotated relative to the base in turn. This produces four walls and a base, and four triangular elements positioned outside of the volume enclosed by the four walls and the base. The four triangular elements may then be positioned adjacent one of the walls from which they are formed. This may be the end of the process. In one alternative embodiment the triangular elements may then be attached, for example by an adhesive to said wall. A four walled tray is then produced without the need to tear, or weld any portion of the tray. The tray is therefore strong and resistant to corrosion and heat. As welding is not required this reduces the energy required to form the tray.

Figure 8 shows a sheet of material 31 with an indentation. If the first and second lines were determined in the same manner irrespective of the indentation 42, then a square would not be formed. Therefore, the first line 37 is positioned such that it is situated below the indentation 42 by the same distance as the distance between the second line 36 and the second side of the sheet of material. This forms a square 35 below the indentation 42. The method can then be performed in the same manner as described above. The resulting three-dimensional corner will of course have a first side that is taller than the second side, but nevertheless a three-dimensional corner is still produced. It is noted that if a protrusion is situated at the corner it may be removed, for example by cutting it off. Alternatively, as long as it ignored in the creation of the diagonal of the square in the corner of the sheet of material then the above method may be practiced without any substantial modification.

Turning now to uses of apparatus made using the above described method, a fire barrier is shown in Figure 9. The fire barrier comprises a metal plate 10 that is secured to the base of at least one masonry support bracket 11, which may otherwise be of conventional construction with a back plate 12 and integrally formed projecting side plates 13. The back plate 12 is adapted to be secured, in use, to a support structure (not shown) comprising an inner skin of a cavity wall, for example by fasteners (not shown). The side plates 13 are adapted to be secured to a support plate 14, which is itself adapted to locate between two adjacent courses 15, 16 of masonry forming part of an outer skin 17 of the cavity wall, the support plate 14 thereby supporting the masonry of the outer skin 17 above it. In the illustrated embodiment the support plate 14 is integrated with the bracket 11 by being welded thereto. However, in other embodiments, the support plate 14 may comprise a separate component that is secured to the side plates 13 of the bracket during construction, typically by slotting into apertures provided in the side plates 13. In still further embodiments the masonry support bracket may be manufactured using the method described above in relation to Figures 1-8. For example, the back plate may be formed of the base of the sheet of material as detailed above, whilst the side plates may be formed from the side lips of the sheet of material. This may minimise the amount of welding required to form the masonry support bracket.

The metal plate 10 is constructed in the manner described above in relation to Figures 1-8. This creates a metal plate with the required shape that includes no welded corners. The lack of welded corners means that the metal sheet can be made thinner than previous fire barriers. Moreover, the lack of welded corners increases the strength of the metal sheet which is especially useful at high temperatures as this increase of strength may increase the amount of time for which the fire barrier is fire resistant. This may therefore give users of the building longer to evacuate to safety. The metal sheet 10 is preferably attached to the bracket 11 or to a series of spaced brackets 11 and has an L-shaped cross-sectional profile, with a leg 18 and an integrally formed foot 19. The leg 18 is secured to the side plates 13 so that it projects outwards from the or each bracket 11 to an extent sufficient to span the cavity formed between the inner and outer skins of the wall.

It will be appreciated that the leg 18 lies adjacent but below the support plate 14 when in use and while it does not need to project outwards from the bracket or brackets 11 to the same extent as the support plate 14 it projects sufficiently for it to abut the outer skin 17. Preferably, however, it projects sufficiently that it not only abuts the outer skin 17 but is located between the same adjacent courses 15, 16 of brickwork as the support plate 14 and is thereby mortared into the outer skin 17. The foot 19 lies adjacent the rear of the back plate 12 and may also be secured thereto. In use, the foot 19 is therefore clamped between the or each bracket 11 and the inner skin (not shown) of the cavity wall. Hence, the metal plate 10 bridges and closes the cavity between the inner and outer skins of the wall. This restricts the spread of smoke and flames through the cavity should a fire arise.

A second embodiment of fire barrier is shown in Figs. 11 and 12. Here, a metal plate 20 is secured to the top of a bracket 11 or series of brackets 11, which are of identical construction to those described above and shown in Figs. 9 and 10. The metal plate 20 is also similar to the plate 10 described above but inverted so that its foot 19 depends down behind the back plate 12 of the bracket 11 and its leg 18 projects forwards. Again the leg 18 projects outwards from the bracket sufficiently to abut the outer skin 17 of a cavity wall and again preferably extends sufficiently to be located and secured between two adjacent courses of masonry 15, 16 of the outer skin 17.

In order to provide at least 30 minutes fire resistance, the metal plate 10, 20 of the barrier needs to be made of steel plate that is at least 0.5 mm thick. Preferably, however, the metal plate 10, 20 is comprised of stainless steel and has a thickness between 0.5 mm and 2.0 mm inclusive. Thicker plates have more rigidity, which improves their efficiency should a fire arise as they take longer to warp and buckle owing to the heat of a fire. Thicker plates also increase the fire resistance period to around 2 hours, which is an important consideration in high-rise structures where evacuation from upper floors may take longer than 30 minutes after a fire has broken out. However, in some circumstances the space for a fire barrier may be small and therefore having a thinner fire barrier may advantageously allow additional fire barriers to be installed within a structure as a result of their thinner profile.

During construction of a building, the size, position and securement of the masonry support brackets 11 to an inner skin of a cavity wall is finely adjusted so that the support plate 14 readily locates between two adjacent courses of masonry in the outer skin 17. This ensures that the position of the metal plate 10, 20 is also finely adjusted at the same time so that it can do the same. The combination of the metal plate 10, 20 with the masonry support bracket 11 or brackets 11 therefore facilitates the positioning within a cavity of a fire barrier. In addition, it obviates the need for the barrier to be cut to slot over existing masonry support brackets 11 and maximizes the space available within the cavity to fit the masonry support brackets 11.

Hence, it will be appreciated that a fire barrier in accordance with the present invention provides considerable advantages over prior art barriers, simplifying both their construction and fitment.

There is also described a cavity tray system 1 which is to be positioned within the cavity 72 of a cavity wall 73 as is shown in Figure 13. The cavity tray is formed using the method described above with reference to Figures 1-8. The cavity wall 73 comprises an inner leaf, or interior building wall, and an outer leaf, or external wall or cladding, which will typically form the exterior of the building, with a cavity 72 there-between. As shown in Figs. 13, 14 and 15, a first, two-piece cavity tray system 71 according to the present disclosure comprises two separate elements, a first cavity tray 80 which is for connecting to the inner wall of the cavity wall 73; a second cavity tray 90 which is for integrating with the outer, exterior wall of the cavity wall 73. This two-piece system allows for flexible and easy integration of the cavity tray system 71 within a building, whilst also ensuring that appropriate directing of water, or any other liquids, which exist within the cavity 72 of the cavity wall 73 are directed appropriately and guided out of the cavity 72, as indicated by the arrows in the Figures.

The first cavity tray 80 is seen in Fig. 15 as comprising an angled planar structure which is to be, or is, attached to the inner wall of the cavity wall 73. It will be noted in the following that each of the planar sections is shown to be flat, and without surface decoration or further shapes; this is by way of example only. Indeed, each tray comprises a respective first surface which is used and adapted for guiding liquids out of the cavity 72; in the following these first surfaces are defined as planar sections. The present disclosure also covers not-flat surfaces, or "planar sections", perhaps exhibiting a slight curve, if beneficial. Additionally, the present disclosure covers "planar sections" which are ridged, or corrugated or have other, non-linear cross-sections. The primary requirement of the planar sections and portions is to ensure that water or other liquid droplets are properly directed from the cavity 72 to the outside of the cavity wall 73. To this end, the term "planar" is not be construed in a literal and restrictive sense, rather it is to be understood functionally as providing an appropriate surface for guiding droplets out of the cavity 72. The tray is manufactured in accordance with the method described above with reference to Figures 1-8. Therefore, the cavity tray is integrally formed and is formed without the use of welding.

The first cavity tray 80 has a surface providing a first planar section 81, for attachment to the interior wall of the cavity wall 3. The first planar section 81 is preferably provided with a series of holes 82 there-through which allow easy fitting of the first cavity tray 80 to the inner wall of the cavity wall 73. Fig. 15 shows generally round holes 82, however it will be appreciated that other fixing structures are appropriate; these may include elongate slots through which a fixing element, for example a screw of bolt, can be threaded for attachment to the interior wall of the cavity wall 73. Additionally, it is understood that the mechanism of fixation could be one of providing hook-like slots in the first planar section 81, wherein the hook-like slots (not shown in the Figures) could be used to hang the first cavity tray 80 to the interior surface or wall of the cavity wall 73. If the interior wall were to be made from a brick-like construction, such that a mortar course were provided between bricks, the first planar section 81 could be provided as an upper lip 89 which can be inserted into the mortar course or any other element of the inner leaf, in order to fix the first cavity tray 80 within the cavity 72 of the cavity wall 73. It will be appreciated that a number of different mechanisms for attaching the first cavity tray 80 are available, and will be chosen appropriately with the nature of the building.

The first cavity tray 80 also comprises another surface providing a second planar section 83, which is shown angled away from the interior wall of the cavity wall 73.

The first cavity tray 10 is preferably an integral structure made of a single sheet of material which is bent or cranked to form the first planar section 81 and the second planar section 83 angled with respect to the first planar section 81. It will be appreciated from Fig. 15, that when the first planar section 81 is appropriately affixed to the interior surface of one of the walls in the cavity wall 73, the second planar section 83 is angled away from this interior surface and provides a skirt-like structure which extends into, and generally across, the cavity 72 of the cavity wall 73. As can be seen from the arrows in the Figures, especially in Fig. 15, liquid which drops down through the cavity 72 will come into contact with the second planar section 83 and be appropriately guided along the surface of the second planar section 83 and away from the wall to which the first cavity tray 80 is affixed. In this manner, moisture and water droplets which are within the cavity 72 of the cavity wall 73 will be guided away from the walls by the first cavity tray 80.

As is also seen in Fig. 15, the cavity tray system 71 comprises a second cavity tray 90. As shown in Fig. 15, the second cavity tray 90 is intended to be positioned below the first cavity tray 80 when the cavity tray system 71 is in use. The second cavity tray 90 comprises an elongate section 21 which, preferably, is so sized and structured that it will allow embedding within the mortar course of the exterior wall making up the cavity wall 73. Of course, it is also possible to reverse the positioning of the first cavity tray 10 and second cavity tray 90, such that the brick structure as shown in the Figures comprises the inner leaf, inner wall, or building wall, of the cavity wall 73. As is clear from Fig. 15, the elongate section 91 will be firmly held within the mortar of the brick construction wall, thus holding the second cavity tray 90 within the cavity wall 73. It is possible to provide the elongate section 91 with a number of holes or elongate slots 93 therein. The provision of such elongate slots 93 allows for the mortar within the mortar course of the outer wall to pass from the lower to upper side of the elongate section 91 and thus ensures reliable and solid fitting of the elongate section 91 within the mortar course in the wall.

As can be seen in Fig. 15, the second cavity tray 90 also comprises an upturned lip 92 extending out of the plane of the elongate section 91. The upturned lip 92 is intended to facilitate the flow of water from the cavity 72 out of the cavity 72. Provision of the second cavity tray 90 with merely the elongate section 91, would allow for water droplets to move in both directions, as seen in Fig. 15 from left to right, and thus drop within the cavity 72 of the cavity wall 73 and not be guided out of said cavity 72. The upturned lip 92 will ensure that water which lands on the elongate section 91 cannot spread and fall off the tray 90 into the cavity 72 but will be guided through and out of the cavity 72.

In order to facilitate the drainage of the water out of the cavity 72, the brick course in a brick construction wall is provided with a series of weep holes. These weep holes pass from the interior of the cavity 72 to the outside of the cavity wall 73, and thus ensure that any liquid or moisture which has been captured by the cavity tray system 71, in the manner described above, will drain out of the cavity 72. The weep holes are shown between bricks in the wall, however may also be possible to position such weep holes within a mortar course of the wall as needed.

It will be appreciated that the two-piece construction to the wall cavity tray system 1 is particularly advantageous as this allows a great deal of flexibility and ease in attaching the cavity tray system 71 within a cavity wall 73. Providing a single piece construction which is intended to bridge from the interior side of the interior wall of the cavity wall 73 across the cavity 72 and then through the exterior wall of the cavity wall 73, puts undue strain on the accuracy of building the cavity wall 73. Furthermore, it is not uncommon for buildings to settle with time, thus meaning that the interior and exterior wall of the cavity wall 73 may move with respect to each other during time, or during different seasons where temperature changes will affect the structures and elements thereof differently. The two-piece construction is, therefore, desirable for ensuring appropriate handling of moisture within the cavity 72, whilst also improving the ease of construction. It will be seen from the Figures that the lengths of the first cavity tray 80 and second cavity tray 20 are preferably the same, such that easy overlap of the two trays will arise.

Figs. 17a to 17c show a modification of the jointing lip 121. The drainage jointing lip 128 has a first taller section 128a towards the upturned lip 22 of the second cavity tray 20. A shorter section 128b is then provided extending from the taller section 128a to the front of the second cavity tray 20 which will be held within the outer leaf of the cavity tray 3. The shorter section 128b of the drainage jointing lip 128 is formed by folding over the top of the short section 128b of the drainage jointing lip 128 back into general contact with the elongate section 91 of the second cavity tray 90. As can be seen in the face-on view in Fig. 17b, the folded over section of the drainage jointing lip 128 creates a lip weep hole 129. This lip weep hole 129 functions in the same way as the weep holes 126 in the weep hole clasp 125, and extends through the mortar of the external leaf of the cavity wall 73. This lip weep hole 129 therefore provides a drainage channel from the interior of the cavity wall 3 to the exterior. The taller section 128b of the drainage jointing lip 128 can be used in combination with a lip cap 130, as shown in Fig. 17c. The lip cap 130 has the same general form as the cap 116, and is utilised to grip together the two taller sections 128b of the drainage jointing lip 128 in order to hold together the adjacent second cavity trays 90. The lip clasp 130 can have either a V-shaped profile or U-shaped profile, in the same manner as cap 116, and after positioning over the taller sections 128b of the drainage jointing lip 128 can be crimped or seamed to the taller section 128b of the drainage jointing lip 128 thus holding together the two portions of adjacent cavity tray 90.

In each of the above concepts, the material making up the elements is of a nonflammable nature. This appropriately reduces any fire concerns in modern buildings. Most preferably, the material for each of these elements is stainless steel, as this does not rust and has a very high melting point and is considered to be a safe material choice. Furthermore, it will be clear that the individual elements of each of the options can be appropriately combined with other elements to make a complete modular system of water handling. In order to provide even further water-tightness, each of the elements, once fitted, can be provided with an appropriate sealant at the edges with other elements of the cavity tray systems of with the walls of the cavity wall 73. In order to facilitate this, it will further be appreciated that the angle which the second planar section 83 of the first cavity tray 10 makes with the interior wall of the cavity wall 73 would preferentially match the angle which the skirt-like structure makes with the interior wall.

Claims

CLAIMS1. A method for producing a three-dimensional corner from a sheet, comprising the steps of: providing the sheet of material with an X-Y plane; determining a first line along the X axis of the X-Y plane of the sheet of material; determining a second line along the Y axis of the X-Y plane of the sheet of material, wherein the first line and the second line are arranged such that they intersect and form a square in a corner of the sheet of material; bending the square in the corner of the sheet along the diagonal of the square formed that ends in the apex of the sheet of material; bending the sheet of material along the first line and rotating the material between the first line and the edge of the sheet of material; bending the sheet of material along the second line and rotating the material between the second line and the edge of the sheet material such that the square in the corner of the sheet of material is bent in half into a triangle and positioned outside of three dimensional corner created in the material; bending the triangle to attach it to one side of the corner of the three dimensional corner.
2. The method of claim 1, wherein no welding is involved in the creation of the three-dimensional corner.
3. The method of any preceding claim, wherein the sheet is formed from metal.
4. The method of claim 3, wherein the sheet is formed from stainless steel.
5. The method of any preceding claim, wherein the sheet is planar.
6. The method of claim 5, wherein the sheet has a thickness of between 0.3mm and 2.0mm, and more preferably between 0.5mm and 1.5mm.
7. The method of any preceding claim, wherein the sheet is a rectangular sheet.
8. The method of any of claims 1-6, wherein the sheet is an irregular shape with an indentation on at least one side.
9. The method of claim 8, wherein the indentation is positioned between the first line and the edge of the sheet of material, the method further comprising adjusting the position of the first line such that the indentation is no longer between the first line and the edge of the sheet of material, and such that if extended the first line would pass through the indentation.
10. The method of claim 8, wherein the indentation is positioned between the second line and the edge of the sheet of material, the method further comprising adjusting the position of the second line such that the indentation is no longer between the second line and the edge of the sheet of material, and such that if extended the second line would pass through the indentation.
11. The method of any preceding claims, further comprising repeating the to create a second three dimensional corner.
12. The method of claim 11, further comprising repeating the method to create a tray comprising four three dimensional corners.
13. The method of claim 11, wherein the second three dimensional corner is positioned diametrically opposite the first three-dimensional corner.
14. The method of claim 13, comprising fusing the two three-dimensional corners to form a tray with four sides and a base.
15. A wall cavity tray for positioning within the cavity of a cavity wall in order to direct water towards the exterior of a building structure, the cavity formed using the method of any previous claim.
16. The wall cavity tray of claim 15, wherein at least one corner of the tray is formed using the method of any of claims 1-14.
17. The wall cavity tray of any of claims 15 or 16, wherein at least one corner of the wall cavity tray is free from welding.
18. The use of a wall cavity tray of any of claims 15-17, wherein the cavity tray is used in the construction of a building.
19. A wall cavity tray system comprising first and second cavity trays, each comprising a first surface, that, in use, are adapted to be located at an angle to one another within the cavity; the first surface of the first tray being adapted to be angled downwardly across the cavity in a direction from an inner leaf of the cavity wall towards an outer leaf of the cavity wall; and the first surface of the second tray adjoining a lower portion of the first tray and being adapted to extend into the outer leaf of the cavity wall, wherein at least one of the first and second cavity trays is a cavity tray of any of claims 1517.
20. The wall cavity tray system of claims 191 wherein the first tray further comprises a second surface, the first and second surfaces of the first tray being integrally formed and angled with respect to each other.
21. The use of a wall cavity tray system of any of claims 19 or 20, wherein the wall cavity tray system is used in the construction of a building.
22. A fire barrier for slowing or preventing the spread of fire through a building, wherein the fire barrier is formed using the method of any of claims 1-14.
23. The use of a fire barrier as set out in claim 22, wherein the fire barrier is used during the construction of a building.
24. A building comprising the cavity tray of any of claims 15-17, or a fire barrier of claim 22.