EP0275145A2

EP0275145A2 - Cladding for buildings

Info

Publication number: EP0275145A2
Application number: EP88300058A
Authority: EP
Inventors: Kenneth Crozier
Original assignee: CROZIER CONSTRUCTION Co Ltd
Current assignee: CROZIER CONSTRUCTION Co Ltd
Priority date: 1987-01-10
Filing date: 1988-01-06
Publication date: 1988-07-20
Also published as: GB8700527D0; EP0275145A3

Abstract

Cladding for a building comprising a plurality of cladding panels wherein opposing edges of adjacent panels form an overlap which extends round and engages with a load dispersing head of a bracket secured to the building characterised in that a major part of at least one of the edges forming the overlap is in continuous engagement with the load dispersing head.

Preferred cladding utilises brackets in the form of either continuous rods or formed by shaping the edge of a panel and the use of composite panels consisting of two flexible weather resistant sheets separated by a layer of flame resistant thermal insulant such as mineral wool or a phenolic plastics foam.

Description

This invention relates to an improved form of cladding or buildings and in particular to improved roofing for industrial buildings.
A form of roofing which is employed frequently comprises cladding panels made generally of sheets of aluminium or steel, opposing edges of which are shaped so that they can fit over the top of a bracket. The latter is secured to a purlin of a building with the bracket extending at right angles from the purlin and the edges of the adjacent panels overlap each other round the end of the bracket so as to form a weather-tight connection. A panel will span a number of purlins to each of which a separate bracket is attached.
Accordingly this invention provides cladding for a building comprising a plurality of cladding panels wherein opposing edges of adjacent panels form an overlap which extends round and engages with a load of dispersing head of a support secured to the building characterised in that a major part of at least one of the edges forming the overlap is in continuous engagement with the load dispersing head.
In known forms of cladding overlapping edges of adjacent panels are shaped round the end of the support and maintained in position by clips. In other instances the clips are dispensed with and the edges of the panels are held round the end of the support by the natural springly qualities of the material forming the panel. If as is usually the case a panel spans a number of purlins the overlapping parts of the panels are held most tightly together in the immediate vicinity of the purlin where the support is located. However between the supports some separation of the overlapping parts is liable to occur. Furthermore the cladding panels do not receive the same degree of support. In accordance with the present invention the load bearing head of the support is in engagement with the overlapping parts of the panels along substantially the whole length of the overlap. In order to achieve this in the case where, as is frequently the case, the panels may span a number of purlins a support is used preferably in continuous lengths with fastening means connected to or forming part of the support to enable it to be secured to the purlins. Screws or bolts are used as fixing means according to whether the purlins are made of wood or metal.
When a support provides a load dispersing head which is in continuous engagement with the overlapping parts of the panels it enters more extensively into the structure of the roof than is the case when individual widely separated supports providing intermittent support are used. As a result the roof has been found to be stronger. This increased strength can be used in different ways. For example, less metal can be employed in the construction of the roof or the purlins can be spaced more widely apart. One especially important application of the present invention comprises shaping an edge of each of the panels so that it is converted into a support thus enabling the combined support and panel to be secured to a purlin without any additional supports.
This invention is now illustrated but not restricted by the following drawings.

Figures 1A and 1B are exploded perspective part sectional drawings of one form of cladding made according to the invention.
Figures 2A and 2B, 3A and 3B are similar drawings showing alternative forms of the cladding.
Figure 4 shows a drawing in perspective of part section of a cladding panel having an edge which has been shaped to form a support.
Figure 5 is an end view taken in vertical section of another form of cladding panel.

In Figures 1A and 1B a support (1) made from continuous lengths of rod or strips of extruded aluminium or steel is secured to purlins (3 and 4) by screws (5 and 6) and bracket washers (7 and 8). The drawing shows two purlins. However depending on which building support members are used to support the panels the number of members to which the continuous length of support is to be secured can vary considerably. The support terminates in a load dispersing member head (9). The support supports adjacent cladding panels (10 and 11) which conveniently can consist of sheet aluminium having a thickness of about 9mm, or sheet steel having a thickness of about 7mm and provided preferably with a corrosion resisting coating. However flexible sheets of other weather resistant materials can also be used. These dimensions are not especially critical since sheets having other thicknesses can be employed so long as they have sufficient strength to enable them to perform their function satisfactorily and, at the same time, they are not too thick and heavy to handle. The edge of panel (11) is shaped so that it conforms to three sides of part of the supper surface of load dispersing head (9) and covers a capillary fold (13) formed by the opposing edge of panel (10). The adjacent panel (10) also has its edge (14) shaped so that when in position the edge overlaps the edge of panel (15), capillary fold (16) formed into the edge of panel (15) and almost the whole of load dispensing head (12). The process of shaping the edges of the panels and forming overlapping edges round the support head of the next adjacent support is then repeated until the roof or wall has been covered. In the resulting structure the overlapping edges of the panels are in continuous engagement with the support head for the full length of the panels.
The present invention is of special value in the construction of composite cladding in which each cladding panel consists of two skins made from flexible sheets of weather resistant material separated by a layer of thermal insulating material for example foamed plastic or mineral wool. Cladding of this kind is illustrated in Figures 2A and 2B which entails the use of two adjacent panels (20 and 21) which have overlapping edges engaging with continuous load dispersing heads (22 and 23). Panels (20 and 21) form upper skins of a composite panel incorporating insulating material (24) which is contained by lower skins (25 and 26). Cladding formed from double skinned panels described above supported along their entire length by a continuous bracket is exceptionally strong.
The present cladding is required to withstand considerable stresses due both to variations in wind and temperature conditions. Consequently in order to assist the integrity of the cladding to be maintained under extreme conditions the load dispersing head is enlarged preferably with a sheath of a flexible synthetic plastics material, for example, polyvinyl chloride as shown in Figures 3A and 3B. In these figures the two upper panel skins (30 and 31) are separated from the lower skins (32 and 33) by an insulating material consisting of polyurethane foam (34). The edges of the upper skins (30 and 31) overlap and envelop load dispersing heads (35 and 36) which are covered by the sleeves (37) made of flexible plastics material. The heads and sleeves extend the full length of the overlapping edges of the panels.
The sleeves can be applied by pushing a tube made of the flexible material and having a longitudinal slit onto the heads of each support so that the slit in the tube corresponds with and accommodates the stem of the bracket.
One of the advantages of the extra strength of cladding utilising continuous supports is that it enables the thickness of the components of the brackets to be reduced to the extent that the thickness of the panel or in the case of a composite panel of a skin of the panel and of the components can be the same. Consequently an important embodiment of this invention resides in the support being integral with the panel and formed from the panel by appropriate shaping of its edge. This is illustrated in Figure 4A in which a panel upper skin (41) has one edge (42) shaped in the manner to enable it to engage with and surround partially the head of a support. The opposing edge of the panel is shaped so as to provide a support head (43) incorporating a capillary duct (44). The upper skin (41) of the panel is provided with a lower skin (45) and an intervening layer of insulant (46). Support head (43) is in engagement with and partially surrounded by a shaped edge (47) of an adjacent panel (48). A part of the edge and the panel skin has been cut away to expose the method of securing panel skin (41) to a purlin (not shown). A self-tapping screw (49) passes through respectively a supporting washer (50), the upper panel skin (41), a spacer (51) and then finally through lower panel skin (45) before the screw enters the purlin. In this construction the upper skin (41) of the composite panel provides the whole of the bracket.
The strength of a composite cladding often depends in some measure upon the nature of the material employed as a thermal insulant between the two skins of each panel and the bonding of the layer of insulant to the inner surfaces of the skins. However when continuous supports are employed and especially when the supports form an integral part of the panels, composite panels can be designed more readily which do not require any strength to be contributed by the layer of insulant. In such circumstances each panel can consist essentially of a self sustaining box-like structure which can if desired be filled with a greater range of thermal insulants. Thus in Figure 5 a composite panel comprises an upper skin (52) consisting preferably of sheet of steel covered with a protective layer of plastics or a sheet of aluminium. One edge (53) of the skin is shaped to extend round and engage with a load bearing dispersing head of a support (not shown). The other edge (54) of the skin is also shaped to form part of a load dispersing head (55) of a continuous support (56). The upper skin (52) is separated from a lower skin (57) of sheet material which may be the same or different from that forming skin (52). The structure defined by the two skins,bracket (56) and side wall (58) constitute in effect a self sustaining box-like container which can be filled with a suitable thermal insulant, preferably a phenolic resin foam which is not only efficient as a thermal insulant but in addition it possesses a high resistance to flaming. The panel is bolted to purlin (59) by a bolt (60).
In this drawing the support is separate from the support (56). However by appropriate modification of equipment required to shape the edge of a skin (52) the support can be formed as an integral part of the skin.

Claims

1. Cladding for a building comprising a plurality of cladding panels wherein opposing edges of adjacent panels (19 and 11) form an overlap which extends round and engages with a load dispersing head (9) of a support (1) secured to the building characterised in that a major part of at least one of the opposing edges of the overlap is in continuous engagement with the load dispersing head (9).

2. Cladding according to Claim 1 wherein the support is separate from the opposing edges of the panels forming the overlap.

3. Cladding according to either of Claims 1 and 2 wherein the support is in the form of a continuous strip.

4. Cladding according to Claim 1 wherein the edge of one of the panels is shaped to form a bracket incorporating a load dispersing head and the opposing edge of the adjacent panel extends round and engages with the load dispersing head.

5. Cladding according to either of Claims 1 and 4 wherein the load dispersing head is covered by a layer of flexible plastics material.

6. Cladding according to Claim 5 wherein the layer of flexible plastics material is in the form of a preformed tube having a longitudinal slit.

7. Cladding according to any one of the preceding claims wherein each panel comprises two sheets of flexible weather resistant material separated by a layer of a thermal insulating material.

8. Cladding according to Claim 7 wherein the thermal insulating material is a plastics foam.

9. Cladding according to Claim 8 wherein the plastics foam is a phenolic plastics foam.