GB2386618A

GB2386618A - Cladding system for buildings

Info

Publication number: GB2386618A
Application number: GB0206329A
Authority: GB
Inventors: Brian Johnson
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-03-16
Filing date: 2002-03-16
Publication date: 2003-09-24
Anticipated expiration: 2022-03-16
Also published as: GB0206329D0; GB2386618B

Abstract

A cladding system for buildings comprises extruded metal rails 41, each formed with a channel 42, for vertical attachment to a building, anchor brackets for slidable engagement in the channels for fixing slabs of cladding 30 and a load bearing bottom anchor 1 for fixing at the bottom of a rail 41. The brackets include a top anchor bracket 20 having a back plate which slides against the rail and a standoff member which extends upwardly from the back plate in use and carries a depending panel support lug. Each bottom anchor 1 has a bottom wall comprising a recess for receiving the standoff member of a top anchor bracket engaged with a rail fixed below said bottom anchor. The bottom wall of the bottom anchor 1 may comprise two mutually spaced sections each having a panel locating lug upstanding therefrom.

Description

CLADDING SYSTEM FOR BUILDINGS

TECHNICAL FIELD OF THE INVENTION

This invention relates to a system for cladding buildings, internally or externally, with facing slabs, e.g. of marble, granite, slate, glass, concrete etc. BACKGROUND

GB 2 352 255 A discloses a cladding system which includes extruded metal rails for vertical attachment to the structure of a buliding. Each rail is formed with a longitudinal dovetail-shaped channel in which anchor brackets are slidably engaged to hold the facing slabs. Each bracket has a back plate formed with a head for slidable engagement in the channels and a standoff member projects from the back plate to carry support lugs which engage in slots in the top and bottom faces of the slabs.

In buildings which are more than a few metros high it is necessary to include expansion joints. In such a cladding system expansion may be allowed for by inserting load-bearing bottom anchors at the level of each floor in the building leaving a small gap between the top of one rail and the bottom

anchor immediately above. Each bottom anchor includes a back wall for attachment to the building, a bottom wall for supporting the slab of cladding material and a pair of upstanding lugs locate in slots in the bottom face of the slab.

In designing a cladding system for a particular contract it is often required to achieve a stipulated vertical spacing between the slabs which should be uniform throughout the area covered by the slabs. In order to achieve this with the previously proposed system it would often be necessary to install the cladding one floor at a time, commencing with the ground floor. This may be inconvenient as it is often preferable to install all the rails and associated hardware priorto commencing installation of the cladding slabs.

Furthermore, it is may be very difficult to replace individual slabs should they become damaged in the course of their normal lifetime.

The present invention seeks to provide a new and inventive form of cladding system which is easier to install, allows a uniform spacing to be achieved with fewer design constraints, and which facilitates the replacement of slabs should it become necessary to do so.

SUMMARY OF THE INVENTION

The present invention proposes a cladding system for buildings which includes: - extruded metal rails each formed with a longitudinal channel for vertical attachment to the structure of a building; - anchor brackets for slidable engagement in said channels for fixing slabs

of cladding material, the brackets including a top anchor bracket having a back plate which slides against the rail and a standoff member projecting from the back plate which carries a depending support lug; - a load-bearing bottom anchor for fixing at the bottom of a rail, said bottom anchor having a back wall, a bottom wall for supporting a slab of cladding material and at least one lug upstanding from the bottom wall for locating the slab; characters Ed in that the standoff member of each top anchor bracket includes a portion which extends upwardly from the back plate, and the bottom wall of the bottom anchor includes a recess for receiving the standoff member of a top anchor bracket engaged with a rail fixed below the bottom anchor.

The bottom wall of the bottom anchor may be formed by two mutually spaced wall sections.

The bottom anchor preferably has a pair of locating lugs which are upstanding from the bottom wall on opposite sides of the recess to engage the slab.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description and the accompanying drawings referred to therein

are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings: Figure 1 is a front view of a bottom anchor for use in a

cladding system in accordance with the invention; Figure 2 is a top view of the bottom anchor, Figure 3 is an end view of the bottom anchor; Figure 4 is a front view of a top anchor bracket for use in the cladding system; Figure 5 is a side view of the top anchor bracket; Figure 6 is a bottom view of the top anchor bracket; Figure 7 is a general view of part of a slab of cladding material for use in cladding system; and Figure 8 is a vertical section through part of a cladding system in the region of an expansion joint, which incorporates the bosom anchor and the top anchor bracket.

DETAILED DESCRIPTION OF THE DRAWINGS

The following description relates to a modification of the cladding system

disclosed in GB 2 352 255 A, the entire contents of which is incorporated herein by reference. Briefly, the cladding system includes a system of rails for vertical attachment to the structure of a multi-storey building with brackets slidably engaged in the rails to hold facing slabs. Load bearing

bottom anchors are used at the level of each floor to dead-load the slabs from the ring beam or floor slab of the building.

Fig.s 1 to 3 show a bottom anchor 1 for use in the present cladding system.

The anchor is formed of a block of structural grade aluminium alloy such as TO alloy, forming a substantially rectangular back wall 2. A pair of mutually spaced co-planar bottom wall sections 3a and 3b project forwards from the lower of the two longer horizontal margins of the back wall 2 forming an intervening gap or recess 4. A pair of support lugs 5 and 6 project upwardly from the front margins of the respective bottom wall sections 3a and 3b. In order to avoid a sharp junction with the back wall which would present a point of potential weakness the front face of the back wall leads smoothly into the top face of each bottom wall section 3a and 3b via an arcuate area 7 (Fig, 3). In addition, a pair of triangular strengthening fillets 8 and 9 join the opposed side margins of each bottom wall section to the back wall 2.

The back wall contains countersunk fixing holes 10, and a short dovetail-

shaped channel 11 is formed centrally in the top face of the back wall, opening through the front face of the back wall 2.

Fig.s 4 to 6 show a top bracket 20 for the present system. The bracket 20 is again formed of structural grade aluminium alloy and include a back plate 21 having a central vertically-extending dovetail-section head 22. A standoff element 23 projects from the front surface of the back plate 16. The standoffwall includes an upwardly inclined portion 24 which leads into a flat horizontal portion 25 which has a locating lug 26 depending perpendicularly from its front margin. Again, the junction regions are curved at 27 to avoid weaknesses at sharp corners.

The facing slabs may, for example, be of a quarried material such as marble or granite cut to standard dimensions. As shown in Fig. 7, the slabs 30 have spaced anchoring slots 32 cut into their upper and lower faces with shallow recesses 33 extending from the slots to the rear face of the slab.

The bottom anchors and top brackets are used with rails as shown in Fig. 8. The rails 41 are extruded from an structural grade aluminium alloy which may be supplied in standard lengths (e.g. 3.5 m), several of which can be used to form a longer rail if necessary. The extrusion is of rectangular bar section formed with a dovetail-shaped channel 42 which opens centrally through a front face of the extrusion. Countersunk fixing holes (not shown) are provided at intervals along the rail on opposite sides of the channel 42.

A bottom anchor 1 is fixed to the structure of the building, e.g. an external wall 50, at the approximate level of each floor 52 immediately above a structural expansion joint 53. The anchor may be secured by inserting standard fixing elements (e.g. bolts or screws) through the fixing holes 10.

One or more vertically aligned rail sections 41 are then similarly secured to the building immediately above the anchor 1. The lower end of the channel 42 is aligned with the channel section 11 allowing the anchor to be connected with the lower end of the rail 41 by means of a short dovetail-

section locating piece (not shown) if desired. At the level of the next floor up, the rail 41 terminates short of the next anchor bracket to form a small expansion gap 56. The rails and bottom anchors are fixed at predetermined horizontal centres. The channel 42 may receive one or more intermediate brackets of the kind disclosed in GB 2 352 255 A, but a top bracket 20 is always used at the upper end of the rail.

When the rails, anchors and brackets have been installed the slabs are

secured by locating the lugs 5 and 6 of the bottom anchors 1 in the bottom slots 32 of the lowermost slab, as shown. The intermediate brackets (if required) are located in the top slots 32 of each slab and the bottom slots of the slab immediately above. The vertical spacing between the slabs is thus determined by the dimensions of the intermediate brackets. At the top of each rail 41 the top anchor bracket 20 is slid up to the top of the rail so that the top portion of the bracket enters the recess 4 of the adjacent bottom anchor 1, as shown in ghost outline. This allows the slab 30 to be moved into position, following which the top bracket 20 can be lowered into engagement with the top slot 32. It is thus possible to achieve a relatively close spacing between the slabs in the region of the expansion joint, which can be made to match the spacing determined by the intermediate brackets.

Mastic sealant (not shown) will normally be inserted between the slabs and within the slots 32.

Cladding systems are often designed to have a minimum life of about 100 years. Nevertheless, it may sometimes be necessary to replace intermediate slabs in a multi-storey building. With the present system this could easily be achieved since, by moving the top brackets into the recesses 4, the slabs of one storey can be removed without disturbing the slabs of the storeys above.

Although marble and granite are the most common facing materials the slabs could be of any synthetic or natural material. Other examples include slate, glass and concrete.

It will be appreciated that the features disclosed herein may be present in any feasible combination. Whilst the above description lays emphasis on those

areas which, in combination, are believed to be new, protection is claimed for

any inventive combination of the features disclosed herein.

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Claims

i CLAIMS

1. A cladding system for buildings which includes: - extruded metal rails each formed with a longitudinal channel for vertical attachment to the structure of a building; - anchor brackets for slidable engagement in said channels for fixing slabs of cladding material, the brackets including a top anchor bracket having a back plate which slides against the rail and a standoff member projecting from the back plate which carries a depending support lug; - a load-bearing bottom anchor for fixing at the bottom of a rail, said bottom anchor having a back wall, a bottom wall for supporting a slab of cladding material and at least one lug upstanding from the bottom wall for locating the slab; characterized in that the standoff member of the top anchor bracket includes a portion which extends upwardly from the back plate, and the bottom wall of the bottom anchor includes a recess for receiving the standoff member of a top anchor bracket engaged with a rail fixed below the bottom anchor.

2. A cladding system according to Claim 1, in which the bottom wall of the bottom anchor is formed by two mutually spaced sections and the recess for receiving the standoff member of a top anchor bracket is formed in the space between the two sections.

3. A cladding system according to Claim 1 or 2, in which the bottom anchor has a pair of locating lugs which are upstanding from the

bottom wall on opposite sides of the recess to engage the slab.

4. A cladding system according to any preceding claim in which the standoff member of the top anchor bracket includes: - an upwardly inclined portion which projects in a forward direction away from the back plate, and - a substantially horizontal portion which projects from the top of the upwardly inclined portion to carry the depending support lug.

5. A cladding system for buildings which is substantially as described herein with reference to the drawings.

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