GB2533909A

GB2533909A - Fascia panels

Info

Publication number: GB2533909A
Application number: GB1419002.9A
Authority: GB
Inventors: Richard Irving Matthew
Original assignee: HONEYCOMB SYSTEMS Ltd
Current assignee: HONEYCOMB SYSTEMS Ltd
Priority date: 2014-10-24
Filing date: 2014-10-24
Publication date: 2016-07-13
Also published as: GB201419002D0

Abstract

The panel comprises: a front skin 102 having a front surface 104 and a rear surface 106. The rear surface is sealingly bonded 108 to a peripheral frame 110 and to a structural insert 112 comprising exterior lateral edges 118 extending close to or abutting interior edges 120 of the peripheral support frame. The panel comprises a rear skin 126 having a front surface 124 and a rear surface. The front surface of the rear skin is sealingly bonded 128 to the structural insert and to the frame. The insert is dimensioned to engage the front and rear skins as well as the interior edges of the frame. A composite structure in which no part of the front skin is unsupported is formed. The front skin may made from, e.g. a ceramic, cement or polymer material. The fascia panel may incorporate a structural insert which is a expandable metal foil honeycomb.

Description

Title: Fascia panels

Description:

This invention relates to fascia panels and in particular to ceramic-clad fascia panels suitable for use in architectural cladding systems.

Architectural cladding systems are often used to provide an attractive facade to a building or structure. Decorative facades can be used to update the look of an existing building, to conceal unattractive underlying structures (such as concrete framework) unfinished block etc.) and/or as a "technical skin" for new buildings. Cladding panels can be made up of single material content for example metal sheets, or can comprise multiple layers laminated together forming composite structures or boards.

Conventional cladding is affixed directly to the underlying structure or building frame, for example, ceramic tiles bonded to block work by mortar. However, more sophisticated cladding systems employ both visible and secretly fixed panels onto a secondary support frame affixed to the building from which cladding panels or tiles themselves are hung. The advantages of using panel systems that employ secondary support frames are well known, but generally include the ability to be hung at specific dimensions off the main structure for architectural features and/or to allow insulation to be packed behind the panel, reduced material usage because the use of composite materials enables fewer support frames to carry panels due to spanning capabilities. It is also possible to use a reduced amount of facade material, which can be supported on a cheaper, lightweight support structures.

The hanging of panels onto secondary supports frames can be carried out in many ways, including the use of visible facing clamps through panel joints at specific locations around panel edges, the addition of isolated/continuous extrusions or profiles either bolted or bonded to the rear of the panels to provide support ledges or functional channels to accept clamps or screws to fix to secondary frames. Extrusions can also be added to the rear of panels to provide supports for recessed clamps to brace panels back to supports. Friction clamping panels provide site adjustability, and in some case de-mountability & re-mountability.

However, many multi-layed or composite cladding materials, in existing facade panelling systems, can be prone to the effects of water ingress due to exposed and unprotected edges around the panel perimeter. This can lead to quality and performance issues, such as reduced structural integrity, freeze-thaw deterioration over time, corrosion etc., especially where the composite structure de-bonds or where the supporting structure is discontinuous. If panel layers are not mechanically held together, without adhesion, layers could come free from one another and if delamination occurred post installation, materials or layers could come loose and/or fall from the building itself.

A system that addresses one or more of the above problems is described in UK Patent Application No: 1412334.3, which relates to a cladding system comprising an encapsulated support frame within a metal cladding panel.

This invention, however, relates to a ceramic or rigid sheet materials that cannot be post formed into profiles for cladding systems. For example, existing ceramic granite cladding systems are available in three basic types.

A first type comprises a relatively thick ceramic tile comprising undercut channels or captive nut grooves cut into the rear surface thereof. These systems work by sliding a bolt head or nut into the channel, which retains the bolt/nut to the ceramic tile so that it can be bolted directly to a support system (e.g. to a metal framework) or directly to the facade of the building itself. These tiles are relatively thick, typically 30mm or so in thickness, and are thus quite heavy (thereby requiring substantial supports to hold their weight) and are expensive to produce due to the relatively large amount of ceramic used and the need to provide accurately machined channels or grooves to connect them to a building.

A second type of ceramic cladding system comprises a conventional metal cladding tile system, but with a relatively thin ceramic tile (typically 5mm or so thick) bonded to the front face of the metal cladding tile. Such a system reduces the weight of the tile overall, by reducing the amount of ceramic. However, this type of tile is susceptible to delamination of the ceramic tile from the backing support structure, especially under freeze-thaw conditions.

A third known type of ceramic cladding tile comprises a ceramic tile that forms part of a composite structure, that is to say whereby the ceramic tile forms a front face of the tile, but which is supported from the rear by a peripheral support frame (used to secure the tile to a building) and a reinforcing element, such as a honeycomb structure or plywood, bonded to the rear of the ceramic tile within the boundary of the peripheral support frame. An example of such a known tile is shown schematically in Figure 1 of the drawings.

Referring to Figure 1, a pair of known ceramic cladding tiles 10 are located side-by-side as they would be installed on a building. Each tile 10 comprises a ceramic fascia 12, which has a support core structure 14 bonded to its rear surface 16. The support core structure 14 terminates laterally just short of a peripheral support frame 18, usually manufactured from an aluminium extrusion, which comprises various channels for securing the panels 10 to a building. The peripheral edges 20 of the ceramic fascia 12 are bonded to the peripheral frame 18 by an adhesive bead 22, and a bead of sealant 24 is provided laterally outwardly thereof to inhibit water ingress, which may degrade the adhesive bond of the adhesive bead 22 to the rear surface 16 of the ceramic tile 12 or to the peripheral support frame 18.

The rear 26 of each tile 10, and the reverse of the support core structure 14 is closed off by a rear cladding sheet 38 that is bonded to the back of the core support 14 and which comprises edge returns 30 that fold into a channel 32 provided on the rear of the peripheral support frame 18. Water ingress into the interior 34 of the panel 10 is thus inhibited by the sealant 24, adhesive 22 and by the configuration of the return 30 and channel 32, which together form a labyrinthine obstruction to water ingress.

The known system suffers from a number of disadvantages: First, the rear of the panel 10 is not sealed, and so water can enter the interior 34 of the panel 10 via the route indicated by arrow 36. This can result in water droplets (not shown) pooling within the panel, which may evaporate in hot conditions, leading to penetrating water vapour, as indicated by arrows 37, entering the interior 34 of the panel 10. During cyclical heating and cooling (e.g. day and night), the water evaporates and condenses within the panel 10 leading to deterioration of the bond between the core support structure 14 and the rear surface 16 of the ceramic tile 12, and/or the bond between the core support structure 14 and the front surface 38 of the rear cladding panel. This clearly creates a risk of delamination and/or eventual detachment of the ceramic tile 12, which, if unsupported by the honeycomb structure 14, can readily crack under, say, wind loading.

Second, the core support structure 14 terminates short of the peripheral support frame 18, and with not connecting rear sheet liner results in an unsupported portion 40 of the ceramic tile 12. Such an arrangement tends to create weak points and thus concentrate any loading of the tile 10 in the unsupported region, leading to the risk of failure over time. Water penetration at this point may also risk freeze thaw conditions.

Third, the tiles 10 are susceptible to freeze-thaw attack, as illustrated in Figures 2 and 3 of the drawings, if/when the sealant bead 24 fails. In this situation, water can penetrate the sealant 24 causing it to swell 42 at temperatures approaching or below freezing, and/or water can pool in the region 44 between the sealant bead 24 and the adhesive bead 22. The freeze-thaw effect leads to jacking 42 of the edges of the ceramic tile 12 away from the peripheral support frame 18, eventually leading to failure 46 of the ceramic tile 12 as shown in Figure 3 of the drawings.

A need therefore exists for an improved and/or an alternative panel and/or one that addresses, or overcomes, one or more of the aforementioned problems.

Various aspects of the invention are set forth in the description and appendent claims.

An aspect of the invention provides a fascia panel comprising: a front skin having a front surface and a rear surface, wherein the rear surface of the front skin is sealingly bonded to a peripheral support frame and to a structural insert comprising exterior lateral edges abutting the interior edges of the peripheral support frame, and wherein the fascia panel comprises a rear skin having a front surface and a rear surface, wherein the front surface of the rear skin is sealingly bonded to the structural insert and to the peripheral support frame.

The front skin is suitably manufactured from a ceramic, concrete or polymer concrete material or other rigid material. In certain embodiments, the thickness of the front skin is less than 15mm, less than 10mm or less than 5mm.

The rear surface of the front skin is sealingly bonded to a peripheral support frame, for example, using a heat-curable, or preferably, an air-curable or pressure-sensitive adhesive layer disposed on, and/or spread over the said rear surface. Such an arrangement may provide a uniform bond to the peripheral support frame and to the structural insert. The invention utilises adhesives, which may be of any suitable type. Suitably, contact adhesives are used, and preferably thermosetting adhesive are used that do not significantly outgas during curing. The adhesives, where used, are suitably selected for longevity, speed of curing, durability and compatibility with the materials of the panel.

The structural insert suitably comprises a honeycomb structure, such as an expandable metal foil honeycomb, which is suitably bonded to front and rear skins of the panel, for example, by an adhesive layer. In the illustrated example, a honeycomb structure is used, although it could be of any suitable material, such as plywood. By providing a structural insert, the stiffness and strength of the panel can be hugely improved, whilst at the same time, minimising weight. The honeycomb insert, where provided, can comprise perforations or micro-perforations, which permit air to pass between adjacent cells of the structure. Such a configuration has been found to reduce the incidence of distortion of the panel under differential heating conditions (e.g. one part of the panel in sunlight, with another part being shaded).

The structural insert is dimensioned to engage the front and rear skins, as well as the interior edges of the peripheral support frame. As such, the invention provides a composite structure in which no part of the front skin is "unsupported". This may be facilitated, in certain embodiments, by forming the supporting framework to have a squared-off cross-section thus forming a right angle between its internal periphery and the front and rear skins of the panel, which facilitates expanding a honeycomb structural insert into abutment with the peripheral support frame.

The use of a panel with either a fully continuous structural insert captive within a cavity formed by the front skin, the rear skin and the peripheral support frame is not known from the prior art: known systems generally comprising extrusions that are independent of one or more layers of the panel allowing water ingress into the extrusion area/panel core, or front skins that could fall away from the panel if delamination occurred.

The rear skin is suitably manufactured from a relatively thin, lightweight, sheet material, such as aluminium or plastics sheet, which reduces the weight of the panel whilst still allowing the rear skin to play a structural role in the composite structure.

The peripheral framework may additionally comprise one or more retaining lips that engage with exterior edges of the front skin. Such a configuration suitably permits the weight of the front skin to be mechanically supported on a ledge of the peripheral support frame, thereby reducing the chances of deboning under shear-loading conditions or creep, where a polymer-based adhesive is used. Such a lip, where provided, may be provided around the entire perimeter of the front skin to form a decorative and/or structural border to the front skin, which could serve to protect the edges of the front skin from damage, as may be particularly relevant where the front skin is manufactured from a ceramic material. The lip, where provided, may comprise a return angle which corresponds to a bevel angle of the edge of the front skin. Such an arrangement may serve to positively engage and/or to mechanically engage the front skin with the peripheral support frame.

The peripheral support frame is suitably manufactured from lengths of extruded metal, such as extruded aluminium, extruded steel or extruded stainless steel. The framework portions suitably comprise a functional channel, such as a captive nut channel, which can be used for securing mounting components, which can be used to affix the panel to a supporting secondary framework or directly to a building facade.

The peripheral support frame suitably comprises structural beam portions, which are suitably hollow to reduce weight, and which provide generally planar abutment surfaces that are spaced apart to which the front skin and rear skin of the panel can be adhesively and/or sealingly bonded.

A preferred embodiment of the invention shall now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic cross-section through a pair of known fascia panels; Figures 2 and 3 are close-up views illustrating various failure modes of the fascia panel of Figure 1; Figure 4 is a schematic partial cross-section through the edges of two adjacent fascia panels in accordance with the invention; and Figure 5 is a close-up view of Figure 4.

Referring now to Figure 4 of the drawings, a pair of panels 100 in accordance with the invention are located side-by-side and each comprises a front skin 102 manufactured from a relatively thin ceramic tile. The front skin 102 has a planar front surface 104 forming a decorative facade for, say, a building. The front skin 102 also has a planar rear surface 106; which is coated with an adhesive layer 108. The adhesive layer 108 is continuous and bonds the rear 108 of the front skin 102 to an extruded aluminium peripheral support frame 110 and a honeycomb structural insert 112.

As can be seen, in particular from Figure 5 of the drawings, the adhesive layer 108 extends all the way to the edges 114 of the front skin 102, and the peripheral support frame comprises a planar surface region 116 to which the front skin 102 is adhesively, and sealingly bonded. The honeycomb structural insert 112 extends laterally and has side edges 118 that about the right-angled inner walls 120 of the peripheral support frame 110. As such, no part of the front skin 102 is unsupported by ether the peripheral support frame 110 or by the structural insert 112.

The peripheral support frame 110 comprises a planar rear surface portion 122 to which the front surface 124 of a sheet metal, or sheet plastics, rear skin 126 is adhesively and sealingly bonded by a bead of adhesive 128 spread over the said front surface 124 in contact with the planar rear surface portion 122 of the peripheral support frame 110.

Notable in Figure 5 of the drawings is that the rear skin 126 is cut with a small tolerance, and a recess 127 of the rear of the peripheral support frame 110 is appropriately dimensioned so that the rear skin 126 locates accurately within the recess 127, thereby inhibiting racking of the panel 100. The rear skin's adhesive layer 128 covers the entire front surface 124 of the rear skin 126 thereby bonding the back of the structural insert 112 to the rear skin 126 across the panel's entire surface. This arrangement forms a lightweight, watertight, strong and stiff composite panel, which by virtue of having a sealed interior volume 130 filled by the structural insert 112 is less susceptible to water ingress, and thus freeze-thaw failure.

The peripheral support frame 110 is manufactured from four metal extrusions, whose profiles shall be explained in greater detail below. The ends of the extrusions are cut at 45 degrees to form a mitre joint (not shown) and a corner brace (not shown) is provided at each corner to reinforce the connection.

It can be seen from Figures 4 and 5 of the drawings that the peripheral support frame comprises metal extrusions that each comprise a main body portion comprising a hollow, rectangular cross-section portion 140, a functional portion 142 comprising an undercut, captive nut channel 144.

A channel 146 is also provided for retaining a cover strip 148, as shall be described below.

By adhesively bonding the front 102 and rear 126 skins to opposite sides of the peripheral support frame 110, a sealed internal cavity 130 is thus formed between the front 102 and rear 126 skins, within which the honeycomb structural element 112 is located. Further, by adhesively bonding the honeycomb structural element 112 to the front 102 and rear 126 skins, a strong, lightweight composite panel structure is formed. Moreover, the lateral edges 118 of the honeycomb insert 112 meet the inner side walls 120 of the peripheral support frame 110, and the peripheral support frame thus becomes an extension of the composite panel, thereby forming a continuous structure across the entire width of the panel 110, unlike existing panel systems whereby the honeycomb insert 112 stops short of the support frame leading to a potential concentration of forces between where the honeycomb ends and the support frame begins. Thus, the invention provides manifold advantages over existing systems, thereby meeting some or all of the objects of the invention.

The panels 100 can be affixed to a building (not shown) or a support structure (not shown) by bolt heads or nuts held captive in the captive nut channel 144 of the functional portion 142 of the support frame 110. A decorative closure strip 148 is also located between adjacent panels 100, which strip 148 is retained by the channels 146 previously described.

The invention is not restricted to the details of the foregoing embodiments, which are merely exemplary of the invention. For example, different materials may be used, and the shapes/configurations shown are illustrative of the invention and may be varied depending on design considerations, without necessarily being restrictive.

Claims

Claims: 1. A fascia panel comprising: a front skin having a front surface and a rear surface, wherein the rear surface of the front skin is sealingly bonded to a peripheral support frame and to a structural insert comprising exterior lateral edges extending close to or abutting interior edges of the peripheral support frame, and wherein the fascia panel comprises a rear skin having a front surface and a rear surface, wherein the front surface of the rear skin is sealingly bonded to the structural insert and to the peripheral support frame.
2. The fascia panel of claim 1, wherein the front skin is manufactured from any one or more of the group comprising: a ceramic material; a concrete material; a polymer concrete material; a ceramic tile; a glass or glass-like material; natural stone; and reconstituted or manmade stone.
3. The facia panel of claim 1 or claim 2, wherein the thickness of the front skin is less than 15mm.
4. The fascia panel of claim 3, wherein the thickness of the front skin is less than 10mm.
5. The fascia panel of claim 4, wherein the thickness of the front skin is less than 5mm.
6. The fascia panel of any preceding claim, wherein the rear surface of the front skin and the front surface of the rear skin is sealingly bonded to the peripheral support frame by any one or more of the group comprising: a thermosetting resin; a thermosetting adhesive; a contact adhesive; a heat-curable adhesive; an air-curable adhesive; and a pressure-sensitive adhesive.
7. The fascia panel of any preceding claim, wherein the adhesive layer substantially covers the entire rear surface of the front skin.
8. The fascia panel of any preceding claim, wherein the adhesive layer substantially covers the entire front surface of the rear skin
9. The fascia panel of any preceding claim, wherein the structural insert comprises a honeycomb structural insert.
10. The fascia panel of claim 9, wherein the honeycomb structural insert comprises an expandable metal foil honeycomb.
11. The fascia panel of claim 9 or claim 10, wherein the honeycomb structural insert comprises perforations or micro-perforations, which permit air to pass between adjacent cells of the structure.
12. The fascia panel of any preceding claim, wherein the peripheral support frame comprises an inner side wall substantially forming a right angle with the front and rear skins of the panel.
13. The fascia panel of any preceding claim, wherein the rear skin is manufactured from a relatively thin, lightweight, sheet material.
14. The fascia panel of claim 13, wherein the rear skin is manufactured from sheet aluminium.
15. The fascia panel of claim 13, wherein the rear skin is manufactured from a sheet plastics material.
16. The fascia panel of any preceding claim, wherein the peripheral support frame comprises a retaining lips adapted, in use, to engage with an exterior edge of the front skin.
17. The fascia panel of claim16 comprising a lip on a plurality of edges of the panel.
18. The fascia panel of claim 17, wherein the lip extends around the perimeter of the front skin to form a decorative and/or structural and/or protective border of the panel
19. The fascia panel of any of claims 16 to 18, wherein the lip comprises a return angle which corresponds to a bevel angle of the edge of the front skin.
20. The fascia panel of any preceding claim, wherein the peripheral support frame is manufactured from lengths of extruded aluminium, extruded steel or extruded stainless steel.
21. The fascia panel of any preceding claim, wherein the peripheral support frame comprises a captive nut channel.
22. The fascia panel of any preceding claim, wherein the peripheral support frame comprises a recess dimensioned to accurately receive the periphery of the rear skin.
23. A panel substantially as hereinbefore described, with reference to, and as illustrated in, Figures 4 and 5 of the accompanying drawings.