GB2187487A - Building, corner unit for use in the building and method of forming a corner - Google Patents

Abstract

A corner unit for the cladding of a building is formed by bending two pieces of cladding sheet adjacent to respective margins to form flanges (4 to 7) and then securing the flanges together to hold the pieces in the required relation. The surface finish of parts other than the flanges is not impaired. <IMAGE>

Description

SPECIFICATION Building, corner unit for use in the building and method of forming a corner Description of Invention The present invention relates to a corner defined by sheet material, for example sheet metal cladding of a building.

U.K. patent, GB 2,120,136 discloses the production of a corner unit for incorporation in the cladding of a building which comprises a steel frame and a cladding of sheet material on the frame. Sheet material used for cladding a building generally has rectilinear formations, for example corrugations, to provide better stiffness than is possessed by flat sheet material of the same weight. Sheet material having such formations is described herein as profiled sheet.

GB 2,120,136 discloses a procedure in which portions of a generally flat profiled sheet are cut-away to form apertures, the sheet is bent along a line joining the apertures to bring cut edges into adjacent relation, the mutually adjacent edges are welded together, excess metal is ground off, the exposed metal is plated with zinc or cadmium, the corner unit is subjected to various surface treatments and is then coated with a layer of a plastics material. The corner unit which has been formed in this way can then be incorporated in a building, during cladding of a frame of the building.

The procedure disclosed in GB 2,120,136 is inconvenient and expensive. However, the requirement for pre-formed corner units is such that the procedure has been used commercially for some time. The incovenience arises particularly from the need to carry out a variety of operations for which different plant is required. Thus, it is generally necessary to start with the galvanised steel sheet, not with plastics-coated steel sheet which is used for straight parts of the cladding. After cutting, bending and welding of the sheet material have been carried out, the fabricated corner unit is typically transported to another site for electro-plating and to yet another site for application of the plastics coating.The resulting finished corner unit does not generally have the same surface finish as is provided on cladding sheets which are to be used in a generally flat condition in juxta-position to the corner unit. Since the same batch of plastics material cannot be used conveniently for coating both the flat sheets and the corner units, differences of pigmentation can arise so that neither the surface finish not the colour of the corner units matches the surface finish and colour of other parts of the cladding.

According to a first aspect of the present invention, there is provided a method of forming a corner in sheet material wherein the sheet material is bent to form a first flange at a margin of a first piece of the material, the sheet material is bent to form a second flange at a margin of a second piece of the material and the first flange is secured to the second flange so that the first and second pieces of sheet material are held in a mutually adjacent relation in which they define the corner.

The first and second pieces of sheet material may be initially separate pieces or may be cut from a single sheet prior to or during bending. Alternatively, the first and second pieces may be integral one with the other.

There can be used conveniently in the method a generally flat sheet selected from a number of identical sheets which are to be incorporated in the cladding of a building, some remaining generally flat and others being formed into corners. The surfaces of the first and second pieces of sheet material which are exposed to view in the completed building can remain unaffected by forming of the corner.

Thus, the surface finish and colour of the cladding at the corner can match exactly the surface finish and colour of other parts of the cladding.

In the preferred method, the surfaces of said pieces of sheet material, other than surfaces of the flanges, are not cleaned, stripped, coated or otherwise modified during formation of the corner. The flanges may be modified, for example being pierced to form holes for receiving fasteners or being stripped in preparation for welding. However, the flanges can conveniently be concealed from view in the finished building so that modification of the surface finish of the flanges is not detrimental to the appearance of the building.

The method of the invention is applicable with especial advantage to profiled cladding sheets. In a case where corrugations or like rectilinear formations of the cladding sheets are required to run to the corner, each of said flanges will be cut into distinct parts arranged in a row at the margin of the corresponding piece of sheet material.

According to a second aspect of the invention, there is provided a building comprising a frame and a cladding of sheet material on the frame and having at least one corner defined by adjacent pieces of the cladding, wherein each of said pieces has at a margin which is adjacent to the apex of the corner a flange and wherein said flanges are secured together.

The adjacent pieces of the cladding may be parts of an external cladding or of an internal cladding and may define an external corner or an internal corner. The corner may be between adjacent walls of the building, between a wall and a roof of the building, between a wall and ceiling of the building or between any other surfaces which are not co-linear.

According to a third aspect of the invention, there is provided a corner unit for use in a building according to the second aspect of the invention, the corner unit comprising two pieces of sheet material with respective mutually adjacent margins, wherein each of said pieces has at its margin which is adjacent to the other piece a flange and wherein said flanges are secured together.

The flanges are preferably secured together prior to mounting of the pieces of sheet material on the frame of the building.

There may further be provided a cover which encloses the flanges. This cover may be formed in situ on the flanges or may be preformed and then mounted on the corner unit.

An example of a method in accordance with the first aspect of the invention and an example of a corner unit in accordance with the third aspect of the invention will now be described, with reference to the accompanying drawings, wherein: Figure 1 shows diagrammatically a profiled cladding sheet at an intermediate stage in preparation of the corner unit; and Figure 2 shows a plan view of the completed corner unit.

The corner unit illustrated in Fig. 2 is prepared from a profiled cladding sheet such as is typically used in a generally flat condition for cladding the frame of a building other than at corners of the building. The sheet is cut into two pieces, indicated at 1 and 2 in the drawing. As viewed in a direction perpendicular to the general plane of the sheet, each cut end may be profiled in a manner corresponding to the cross-sectional profile of the sheet.

Thus, some pieces of the original sheet may be cut away entirely and discarded. However, this is not essential and all parts of the original sheet may be retained in integral relation with one or other of the pieces 1 and 2. The cut which severs the piece 1 from the piece 2 is typically at right angles to the corrugations 3 which extend along the sheet.

A flange is formed along the cut margin of each of the pieces 1 and 2. The flange on the piece 1 is divided by cuts into several distinct parts, some of which are identified by the reference numerals 4 to 7 in Fig. 1. All parts of the flange on the piece 1 are bent in the same direction with respect to the general plane of the sheet, this direction being referred to herein as the rearward direction. In a case where the corner is to be a right angle corner, the flanges are bent through an angle of at least 135 and, possibly, through a slightly larger angle. Thus, the angle included between the piece 1 of sheet material and the flanges on that piece is an acute angle.

After the flanges have been cut into distinct parts and bent to the required relation with the pieces 1 and 2, these pieces are brought together so that the margins of these pieces at which the flanges are provided define an apex of the required corner. The flanges are then in face-to-face relation and may be in mutual contact over substantially their entire areas or be spaced slightly apart. Each flange on the piece 1 is then secured to the corresponding flange on the piece 2, for example by fasteners or by means of welding. In the latter case, it would be necessary to prepare the flanges for welding by removing any surface coating from local areas of the flanges.

This preparation of the flanges could be performed before the flanges are bent. In a case where fasteners are used, these may extend through apertures formed in the flanges or may embrace the flanges without penetrating through them.

The corner illustrated in the drawings is suitable for use as an external corner of a building. Since those surfaces of the pieces 1 and 2 which are exposed at the outside of the finished building have not been impaired by formation of the corner unit, a surface treatment of the pieces 1 and 2 is necessary. A surface coating may be applied to the flanges but we prefer to cover the flanges completely.

The covering may be of a plastics foam material which is applied in a flowable condition to the corner unit and is permitted to set or may be a pre-formed cover which is applied to the corner unit, for example being a pushfit on the flanges.

Whilst the flanges are illustrated in Fig. 2 as projecting at the interior of the corner and bisecting the angle of the corner, the flanges may be bent towards the piece 1 of sheet material so that, for example, the flange 4 lies in face-to-face contact with that piece of cladding.

The corner illustrated in the accompanying drawing is intended to be used as an external corner in either an internal cladding or an external cladding of a building. If an internal corner is required, the flanges would be bent in the opposite direction, prior to being secured together. It will be noted that no fixings are exposed at those faces of the corner structure which are intended to be visible in the finished building.

The joint between the pieces 1 and 2 may be sealed by use of a preformed seal or by use of a seal formed insitu by application of a flowable composition to the joint. In a case where a preformed seal is used, this may be interposed between opposite flanges and may extent over the entire interface between the flanges or over a part only of that interface.

Alternatively, a covering applied to the flanges may be relied upon to seal the joint.

It will be noted that it is unecessary to cut any material away from the sheets during formation of the corner unit. Whilst the invention has been illustrated by the fixing together of two separate pieces of sheet material, the structure illustrated in the accompanying drawing may be modified so that the piece 1 is integral with the piece 2. In this case, the flanges 4 and 7 would be ommitted from the piece 1 and the corresponding flanges om mitted from the piece 2, the sheet material being bent at the mutually adjacent margins of the pieces 1 and 2 above and below an aperture formed by bending back the flanges 5,6 and 7 and the corresponding flanges on the piece 2.

The sheet material may be metallic, possibly with a non-metallic coating, for example plastics coated steel or aluminium.

The features disclosed in the foregoing description, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or any combination of such features, be utilised for reasling the invention in diverse forms thereof.

Claims (10)

1. A method of forming a corner in sheet material wherein the sheet material is bent to form a first flange at a margin of a first piece of the material, the sheet material is bent to form a second flange at a margin of a second piece of the material and said first flange is secured to the second flange so that said first and second pieces are held in a mutually adjacent relation in which they define the corner.

2. A method according to Claim 1 wherein the surfaces of said pieces of sheet material, other than surfaces of the flanges, are not modified during formation of the corner.

3. A method according to Claim 1 or Claim 2 wherein the sheet material is profiled cladding sheet, the corrugations or other rectilinear formations of the sheet are required to run to the corner and wherein each of said flanges is cut into distinct parts arranged in a row at the margin of the corresponding piece of sheet material.

4. A method according to any preceding Claim wherein fasteners are used to secure the flanges together and no fastener penetrates the pieces of sheet material other than the flanges.

5. A building comprising a frame and a cladding of sheet material on the frame and having at least one corner defined by adjacent pieces of cladding wherein each of said adjacent pieces has at a margin which is at the apex of the corner a flange and said flanges are secured together.

6. A corner unit for use in a building according to Claim 5, the corner unit comprising a pair of adjacent pieces of sheet cladding, each of said pieces having at a margin which is at the apex of the corner a flange and said flanges being secured together.

7. A building according to Claim 5 or a corner unit according to Claim 6 comprising a cover which covers the flanges.

8. A corner unit substantially as herein described with reference to the accompanying drawing.

9. A method substantially as herein described of forming a corner in sheet material.

10. Any novel feature or novel combination of features disclosed herein or in the accompanying drawing.