GB2615624A

GB2615624A - A glazing assembly

Info

Publication number: GB2615624A
Application number: GB2217641.6A
Authority: GB
Inventors: Llewellyn Jonathan
Original assignee: Standard Patent Glazing Co Ltd
Current assignee: Standard Patent Glazing Co Ltd
Priority date: 2021-11-26
Filing date: 2022-11-25
Publication date: 2023-08-16
Also published as: GB202117091D0; GB202217641D0

Abstract

A glazing assembly comprises a frame having a body portion 1’ for receiving and supporting at least one glazing panel. The body comprises separate first and second components 10’a, 10b, the first on the exterior of a building and the second on the interior. The two components are connected together with a spacer component 40’ to form the body portion. The spacer comprises a material, such as glass reinforced polyamide (GRP), having a lower thermal conductivity than the first and/or second components, and acts as a thermal break. The first component may include a stem 12’ collinear with the spacer. The spacer may be secured to the first and second components by crimping, and may have an external silicone layer. The body portion may include a steel core surrounded by a sheath 42’ formed from a lead alloy. A barrier portion engaging the body portion may overlie at least part of a glazing panel and retaining members may retain the glazing panels in the assembly.

Description

A GLAZING ASSEMBLY

[0001] This invention relates to a glazing assembly, in particular to a glazing assembly for use in glazing roofs and other sloping surfaces of a building.

BACKGROUND

[0002] The term "patent glazing" system refers to a two-edge support system that allows glazed panels to be placed between glazing bars. Patent glazing is commonly used to span open spaces in overhead glazing such as roofs and canopies. The glazing bars provide continuous support along two edges of the glazed panels and are typically fixed to a building.

Channels within the patent glazing bars typically collect rainwater and/or condensation that accumulates within the bar, and drain this to the outside. It will therefore be appreciated that the overhead and often sloping installation conditions for patent glazing systems increase the complexity of design requirements for such systems. For example, intermediate support may be required for the glazing bars depending on their section size, anticipated loads and weight of the glazed panels, to comply with the requisite safety standards.

[0003] The aesthetic qualities of patent glazing systems are also a significant design consideration especially in the context of Heritage properties which have particular design requirements both in terms of aesthetic properties of the glazing system and safety considerations. Traditional patent glazing arrangements were typically made of lead and therefore from at least an aesthetic perspective, lead has often been a material of choice when glazing older buildings, such as those from the Victorian era and particularly those with any historically significant building or planning restrictions, such as in listed buildings, and/or in newer buildings in which a more traditional appearance is sought. More modern alternatives to the traditional lead glazing arrangements are known that comprise aluminium or steel frames.

These aluminium alternatives are often cheaper to produce and provide good weight saving and strength as compared to, for example, wooden frames, and therefore comply with many modern building regulations. However, unlike the traditional lead glazing systems, they are not in keeping with the aesthetics of historical buildings.

[0004] Another problem associated with known glazing arrangements, in particular the traditional lead frames and aluminum frames, is that the relatively high thermal conductivity of these materials can allow significant conduction of heat through various parts of the frame from the warm interior of the building to the colder exterior. This is sometimes referred to as "cold bridging" This can cause problems such as condensation in the glazing arrangement, in particular in the areas where cold bridging occurs. Thermal losses can also occur via heat radiation through the glazing panels, although this can be mitigated to some extent by using a double or triple glazing arrangement, since the gas trapped between the glazing panels provides some insulation. However, even in these arrangements, significant heat loss still occurs through the frame [0005] Some glazing manufacturers have attempted to mitigate the problems associated with condensation in the regions of cold bridging by using "thermal breaks" within the design of the glazing framework. Thermal breaks are components manufactured from one or more materials which have poor heat conducting properties. The thermal breaks therefore minimize or even prevent heat from being conducted through the framework, which causes a reduction or elimination of condensation in the regions of cold bridging.

[0006] In addition to their insulating properties, thermal breaks within a glazing frame may also contribute to the structural integrity of the glazing assembly. Thermal breaks may alternatively be non-structural in nature, i.e. not contribute to the structural integrity of the glazing assembly. Such thermal breaks may also be referred to as isolators. One or more thermal breaks may, for example, be fitted within a cavity formed between two adjacent horizontal and/ or vertical members of the glazing assembly, or between the horizontal/ vertical frame members and an adjacent glazing panel mounted into the glazing assembly. In a patent glazing arrangement, the contribution of the thermal break to the structural integrity of the frame is of particular importance especially from a safety perspective, given that the frame is required to support glazing panels which are mounted above a living or otherwise occupied space. Furthermore, the strength of the frame members of the glazing arrangement determines the span of the glazing opening, which of course will also be determined at least in part by other installation considerations such as the weight of the glazing panels used, including any additional loading considerations, such as those caused by wind, snow, rain and so forth. Use of steel and GRP sections is known in vertical glazing applications. However, these sections are not always suitable for use in patent glazing, for example, due to lacking internal drainage channels. Thus, selection of an appropriate thermal break for use in patent glazing requires careful consideration.

[0007] The present invention aims to address the shortcomings associated with known glazing arrangements, in particular those used for patent glazing.

BRIEF SUMMARY OF THE DISCLOSURE

[0008] In accordance with the present invention there is provided a glazing assembly comprising a frame, the frame comprising a body portion for receiving and supporting at least one glazing panel; the body portion comprising a first component, a second component; the first component and the second component being separate to one another; wherein at least a portion of the first component is configured to be positioned on the exterior of a building; and at least a portion of the second component is configured to be positioned on the interior of a building; and wherein the first component and the second component are connected together with a spacer component to form a substantially continuous body portion, and, wherein the spacer component comprises a material having a lower thermal conductivity than the first component and/or the second component of the body portion.

[0009] The first component of the body portion may comprise a stem.

[0010] The second component of the body portion may be arranged in the glazing assembly such that it is substantially perpendicular with respect to the stem of the first component of the body portion.

[0011] In combination, the assembled first component of the body portion, spacer component, and second component of the body portion may define a substantially T-shaped body portion.

[0012] One or more intermediate components, or materials may be connected to or attachable to the first component and/ or second component and/ or spacer component to define, when connected or attached, a substantially T-shaped body portion. Other shapes of body portion may also be formed by assembling one or more components, optionally including a spacer component, to define a substantially continuous body portion.

[0013] The first component and/ or the second component of the body portion may be formed using an extrusion process.

[0014] One or more components of the body portion may comprise one or more drainage channels.

[0015] The spacer component, hereinafter referred to as "thermal break", may comprise a material having a lower thermal conductivity the first component of the body portion.

[0016] The thermal break may comprise a material having a lower thermal conductivity the second component of the body portion.

[0017] The first component and the second component are therefore connected by a spacer component to define a substantially continuous body portion. This is in contrast with known arrangements which comprise a solid core or body portion which is formed, often by extrusion, as a single, one piece body portion. In some embodiments of the present invention, one or more intermediate components or material, for example but not limited to a foam-based material, may be positioned between the spacer component and the first component and/ or the second component so as to define a substantially continuous body portion.

[0018] By using a thermal break (spacer component) comprising a material having a lower thermal conductivity than the first component and/ or second component of the body portion, and/ or by positioning the spacer component between the first component and the second component of the body portion, thermal conductivity through the body portion is disrupted, i.e. reduced/ minimised/ prevented. In other words, transfer of heat present in the warmer part of the body portion, i.e. the part which is exposed to the interior of a building into which the glazing assembly is fitted, into the colder part of the body portion, i.e. the part which is exposed to the colder exterior of the building, is reduced/ minimised/ prevented by the thermal break positioned between the first and second components of the body portion, due to the low or lower thermal conductivity of the thermal break relative to the material(s) of the body portion.

[0019] The thermal break may comprise a depth of for example, 26mm or 38mm such that, when positioned between the first component and the second component of the body portion, the first component and the second component are separated by the depth of the thermal break. This arrangement means that the combination of the first component, second component and thermal break provides a substantially T-shaped structural body section which forms a significant part of the frame of the glazing assembly. It is to be appreciated that other depths of thermal break may be used to achieve the reduction in thermal conductivity in the context of the present invention.

[0020] An advantage of using the thermal break in this way to form a part of the structure of the frame is that aside from improving the thermal efficiency of the frame by disrupting thermal conductivity through the frame, the thermal break typically comprises material(s) of lower weight than the first and second components of the body portion, meaning that the thermal break can contribute to the strength and structural integrity of the body portion, whilst only contributing a negligible or minor weight increase as compared to using an equivalent sized piece of a material of a greater weight, such as steel.

[0021] The thermal break may comprise a thickness of between, for example 1mm to 6mm. A thermal break comprising a thickness of 3mm may be well suited to certain applications such as Heritage glazing arrangements or slimline glazing arrangements in which a 3mm thermal break can contribute to maintaining the slimline glazing bar profile required for such installations and/ or required so as to be in keeping with an original product.

[0022] The thermal break may comprise polyamide.

[0023] The thermal break may comprise glass reinforced polyamide.

[0024] The thermal break may be arranged such that it is substantially collinear with respect to the stem of the first component of the body portion.

[0025] The thermal break may receivable in one or more channels in the first component of the body portion.

[0026] The thermal break may receivable in one or more channels in the second component of the body portion.

[0027] The thermal break may receivable between one or more flanges in the first component of the body portion.

[0028] The one or more channels, and/or one or more flanges may be located on the stem of the first component of the body portion. For example, the one or more channels, and/or one or more flanges [0029] The thermal break may receivable between one or more flanges in the second component of the body portion [0030] At least a part of the thermal break may be receivable into an extruded portion of the body portion.

[0031] The thermal break may be secured to each of the first component and second component of the body portion using mechanical crimping. Mechanical crimping can be an advantageous method for securing the thermal break to each of the first component and the second component of the body portion, respectively due to the composite nature of the thermal break which prevents it from being welded to the body portion. The mechanical crimping technique facilitates secure joining of the thermal break to the different materials of the body portion.

[0032] The thermal break may comprise a silicone layer.

[0033] Optionally, the silicone layer may comprise a low modulus silicone sealant.

[0034] Potential benefits of using a silicone sealant, for example but not limited to a low modulus silicone sealant is that the silicone sealant provides excellent sealing properties to further protect the glazing assembly from effects of weathering, and the silicone sealant, for example but not limited to a low modulus silicone sealant offers a similar thermal conductivity to that provided by the glass reinforced polyamide thermal break, thus further improving the thermal efficiency of the glazing assembly.

[0035] The silicone layer may define at least a part of an external surface of the thermal break.

[0036] The body portion may comprise a core.

[0037] The core may comprise steel. The core may comprise stainless steel. [0038] The core may comprise carbon.

[0039] The core material may have a percentage elongation of between approximately 20% to approximately 28%, for a stainless steel material. The present inventors have found that this percentage range provides the stainless steel core material with the preferred ductility taking into account the structural nature of the glazing assembly and the deflection forces the glazing assembly is likely to be required to withstand. The present inventors have found that percentage elongation values of below approximately 20% can produce stronger, but more brittle steel, which is not preferred for the glazing assembly.

[0040] The body portion may comprise a sheath that surrounds the core.

[0041] The sheath may comprise a lead alloy.

[0042] The sheath may comprise 99.5% lead and 0.5% antimony. The sheath may comprise between approximately 0.3% to 0.5% Antimony.

[0043] The glazing assembly may comprise a barrier portion. The barrier portion may be configured to engage at least a part of the body portion. The barrier portion may take the form of, or comprise, a weathering extrusion. The barrier portion may take the form of, or comprise, a weathering strip. The barrier portion may be an extruded portion of the glazing assembly.

[0044] The barrier portion may comprise lead.

[0045] The barrier portion may comprise a lead alloy. The lead alloy may comprise 0.3% antimony. The lead alloy may comprise between approximately 0.3% to 0.5% Antimony.

[0046] The glazing assembly may comprise at least one glazing panel. The glazing assembly may comprise at least two glazing panels arranged in parallel to one another. The at least two glazing panels may be arranged in parallel to one another within the glazing assembly such that a cavity is defined between the two glazing panels. The glazing assembly may comprise, for example, three glazing panels. The three glazing panels may be arranged in parallel to one another within the glazing assembly such that two cavities are defined between the glazing panels.

[0047] At least a part of the barrier portion may be configured to overlie a part of the at least one glazing panel. The barrier portion may form a part of a seal arrangement between the glazing assembly and one or more glazing panels received in the glazing assembly. The barrier portion may overlie a peripheral portion of one or more glazing panels.

[0048] The glazing assembly may comprise one or more retaining members for retaining one or more glazing panels in the glazing assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Embodiments of the invention are further described hereinafter with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an embodiment of a known patent glazing assembly, showing a glazing assembly which supports two glazing panels in a parallel arrangement; Figure 2 is a perspective view of an embodiment of glazing assembly in accordance with the present invention; Figure 3 is a perspective view of the embodiment of glazing assembly shown in Figure 2, with the addition of glazing panels; and Figure 4 is an end view of the embodiment of glazing assembly shown in Figure 2.

DETAILED DESCRIPTION

[0050] The known glazing assembly 1 shown in Figure 1 comprises an elongate body portion 10 having a substantially T-shaped cross-section. The T-shaped elongate body portion 10 comprises a stem portion 12 in the form of an elongate bar 12. At a first end 12a of the stem portion 12 are two arm portions 14, 16 each of which extends generally at a right angle from a respective side of the stem portion 12 to define the T-shape of the elongate body portion 10. The stem portion 12 is substantially twice the length of the combined length of the arms 14, 16.

The second end 12b of the stem portion 12 comprises a bulbous-shaped terminus 18, adapted to engage with a weathering extrusion, which is further described below. In this example, the T-shaped elongate body portion 10 is formed by an extrusion process and comprises a S235J mild carbon steel core 24, surrounded by a 90% zinc rich metal primer coating 26.

[0051] The inner-facing surface 22a, 22b of each arm 14, 16, i.e. the surface closest to the stem portion 12, comprises bevelled outer-most edges 24a, 24b. Extending generally perpendicularly from the inner facing surface 22a, 22b on each respective arm 14, 16 are two ribs 26a, 26b, for supporting a first glazing panel 28. The inner-most rib 26b, i.e. that closest to the stem portion 12 extends perpendicularly from the inner facing surface 22a, 22b of the arms and the outer-most rib 26a, i.e. that furthest away from the stem portion 12, extends at around 45 degrees relative to the inner-facing surface 22a, 22b of the arm 14, 16. The ribs 26a, 26b are spaced apart in a parallel arrangement along the length of the arms 14, 16 of the glazing assembly such that a channel 30 is formed between them which assists in distributing the load of a first glazing panel 28. The first glazing panel 28 is supported so that it extends perpendicularly with respect to the stem portion 12.

[0052] Extending inwardly from each side of the second, bulbous end 12b of the stem portion 12 is a glazing support flange 32a, 32b which extend the length of the elongate body portion 10.

Each glazing support flange 32a, 32b comprises a first component 34a, 34h which extends inwardly and away from the bulbous part of the second end 12b of the stem portion at an angle of substantially 45 degrees before extending outwardly substantially parallel with respect to the arms 14, 16 to define a planar surface for engaging and supporting a second glazing panel 38.

The second glazing panel 38 is supported so that it extends perpendicularly with respect to the stem portion 12 and is arranged so that it is parallel with respect to the first glazing panel 28 to define a "double" glazed unit. In the present example, the first and second glazing panels 28, 38 each comprise a glazing thickness of 36mm although it will be appreciated that the invention is not limited to use with glazing panels of any particular thickness since it will be appreciated that dimensions of the glazing assembly 1 components can be altered to suit different thicknesses of glazing panels as required [0053] The first and second glazing panels 28, 38 are separated by a spacer bar 40 in the form of a hollow bar which extends the length of the first elongate body portion 10. The spacer bar 40 maintains a cavity 41 between the first and second glazing panels 28, 38. The cavity 41 aids in insulating the glazing assembly to improve the thermal efficiency of the glazing assembly by creating a void between the warmer, internally positioned first glazing panel 28 and the colder, externally positioned second glazing panel. Depending on the material used for the spacer bar 40, the spacer bar 40 can also act as a thermal break by slowing the heat loss across the spacer bar 40 from the warmer, internally positioned side to the colder, externally positioned side.

[0054] Substantially halfway along the stem portion 12 are two projections extending outwardly from the surface of the stem portion 12 and along its length. These, in the present example, are extrusion artefacts and may or may not be present in one or more embodiments of the invention.

[0055] A barrier portion which might also be referred to as a weathering extrusion 42 overlies an end surface of the second, bulbous end 12b of the stem portion 12 and extends downwardly and outwardly either side of the bulbous end 12b at substantially 45 degrees relative to the stem portion 12, towards the direction of the arms 14, 16, before extending outwardly, substantially parallel to the arms 14, 16 to define a flange 44 either side of the stem portion 12 which is adapted to engage the outer surface of the 7" glazing panel 38. The weathering extrusion 42 comprises a seamless lead alloy comprising 0.3% antimony, formed by an extrusion process.

The weathering extrusion 42 ensures that the glazing assembly remains watertight.

[0056] Although the cavity 41 between the glazing panels 28, 38 and, optionally, the spacer bar (thermal break) 40 provides some improvement in thermal efficiency in the known glazing arrangement, the present invention sought to further improve the thermal efficiency of a glazing arrangement. This has been achieved, at least in part, by modifying the structure of the body portion and reconfiguring the arrangement of the various components of the body portion and the thermal break, as will be explained.

[0057] Referring to Figures 2, 3 and 4, a glazing assembly 1' according to an embodiment of the present invention is shown. Some of the features shown in Figures 2 and 3 correspond to the same general features of the glazing assembly 1 shown in Figure 1. Therefore, the same reference numerals with the addition of a prime symbol are used to denote such features in Figures 2 and 3.

[0058] The embodiment of glazing assembly 1 shown in Figures 2 and 3 comprises an elongate body portion 10' having a generally T-shaped cross-section. However, in contrast to the known elongate body portion 10 shown in Figure 1, the elongate body portion 10' of an embodiment of the glazing assembly 1' of the present invention comprises a first component 10'a and a second component 10'b, separated by a thermal break 40', as will be explained. The first component 10'a comprises a stem portion 12' having a proximal end 12a' which is closest to the second component 10'b of the elongate body portion 10' and a distal end 12b' which comprises a bulbous-shaped terminus 18'. The second component 10'b comprises arms 14', 16' which extend outwardly from a centre point of the second component 10b, in a similar manner to the known arrangement shown in Figure 1, to define the T-shaped portion in combination with the stem portion 12' of the first component 10a. When the glazing assembly 1' is installed, the first component 10'a of the body portion 10' defines the outermost part of the glazing assembly 10', relative to the building façade, i.e. the part which would be visible on the external surface of the building, and the second component 10'b of the body portion 10' defines the innermost pail, i.e. the part which would be visible on the inside of the building.

[0059] In the example embodiment shown in Figures 2 and 3, the body portion 10' comprises a S235J mild carbon steel core which is surrounded by a 90% zinc rich metal primer which ads as a corrosion inhibitor. The body portion 10' is formed by an extrusion process. It is to be appreciated that these materials are merely an example of suitable materials for the core and corrosion inhibitor and may be substituted for other suitable materials in one or more different embodiments of the invention.

[0060] In a similar manner to the known glazing assembly 1 shown in Figure 1, the bulbous terminus 18' of the second end 12b' of the stem portion 12' of the present embodiment of glazing assembly 1' shown in Figure 2 is adapted to engage with a weathering extrusion 42'.

The weathering extrusion 42' overlies the end surface of the terminus 18' and extends downwardly and outwardly either side of the terminus 18' at substantially 45 degrees relative to the stem portion 12', towards the direction of the arms 14', 16', before extending outwardly, substantially parallel to the arms 14', 16' to define a flange 44' either side of the stem portion 18' which is adapted to engage the outer surface of the 2nd glazing panel 38'. The weathering extrusion 42' comprises a seamless lead alloy, comprising 0.3% antimony, formed by an extrusion process and provides a sheath around the steel core of the body portion 10' as well as providing the flanges 44' either side of the stem portion 18' for engaging the glazing panel 38' during site dressing. The weathering extrusion 42' ensures that the glazing assembly remains watertight. It will be appreciated that the weathering extrusion may be arranged in alternative shapes and/ or configurations as compared to the present embodiment, for example to produce a different appearance or sightline on the glazing assembly, if required.

[0061] In the present example, the inner-facing surface 22a', 22b' of each arm 14', 16', i.e. the surface closest to the stem portion 12', comprises right angled outer-most edges 24a', 24b', in contrast to the bevelled edges of the known arrangement shown in Figure 1. However, one or more embodiments of the present invention may comprise bevelled edges on one or both of the arms 14', 16'.

[0062] Extending generally perpendicularly from the inner facing surface 22a', 22b' on each respective arm 14', 16' are two ribs 26a', 26b', for supporting a first glazing panel 28' which is part of a sealed glazing unit 39 comprising the first glazing panel 28' and a second glazing panel 38'. The first and second glazing panels 28', 38' are spaced apart and contained within the sealed glazing unit 39 which is positioned between the flange 44' of the first component 10a' of the body portion 10' and the ribs 26a', 26b'. The inner-most rib 26b', i.e. that closest to the stem portion 12' extends perpendicularly from the inner facing surface 22a, 22b of the arms and the outer-most rib 26a, i.e. that furthest away from the stem portion 12, extends at around 45 degrees relative to the inner-facing surface 22a, 22b of the arm 14, 16. The ribs 26a, 26b are spaced apart in a parallel arrangement along the length of the arms 14, 16 of the glazing assembly such that a channel 30 is formed between them which assists in distributing the load of a first glazing panel. The sealed glazing unit 39 is supported so that it extends perpendicularly with respect to the stem portion 12 such that a first sealed glazing unit 39 is mounted on a first side 14 of the stem portion 12 and a second sealed glazing unit is mounted on a second side 14 of the stem 12, each glazing unit extending generally perpendicular with respect to the stem 12 as shown on Figures 3 and 4.

[0063] In contrast to the known glazing assembly, such as shown in Fig. 1, in the present invention, an example of which is shown in Figs. 2-4, the first component 10'a and the second component 10'b of the body portion 10' are separated by a thermal break 40' which is described more fully below.

[0064] The thermal break 40' acts to disrupt, in this case minimizing or eliminating thermal conductivity between the first component 10'a and the second component 10'b of the body portion 10', thus "breaking" the transfer of thermal energy between the first component 10'a and the second component 10'b of the body portion 10'. The thermal break 40 therefore forms a part of the main body portion 10', i.e. the substantially t-shaped body portion in the present example and therefore contributes to the structural integrity of the body portion 10'. This is significantly different from known glazing assemblies, such as the assembly shown in Fig. 1 in which the thermal break is positioned between the glazing panels and alongside a part of the main T-shaped body portion. In known arrangements, the thermal break does not contribute to the structural integrity of the body portion.

[0065] To hold the thermal break 40' in the present invention, the first component 10'a and the second component 10' of the body portion 10' each comprises a respective retaining clip 46, 48. Each retaining clip 46, 48 comprises stainless steel, which in the present example is AISI 304 stainless steel and extends the length of the body portion 10'. Each retaining clip 46, 46 comprises a generally U-shaped cross section. The retaining clip 46 on the first component 10'a of the body portion 10' depends from the centre of the proximal edge 50 of the first component 10'a to a depth of around 8mm, to a width of around 6mm and a thickness of around 1.5mm, to create a first channel 52 between the sides, or flanges of the retaining clip for receiving a first edge 54 of the thermal break 40'. The retaining clip 48 on the second component 10'b extends upwardly from the centre of the inner facing surface 22a', 22b' of the second component 10'b to a depth of around 8mm, to a width of around 6mm and a thickness of around 1.5mm to create a second channel 56 between the sides, or flanges, of the retaining clip for receiving a second edge 58 of the thermal break 40'. Each of the first and second edges 54, 58 of the thermal break 40' is therefore positioned within the respective channel 52, 56, defined by the sides/ flanges of the retaining clip, in each of the first component 10'a and second component 10'b, respectively, of the body portion 10'. At least the sides or flanges of the retaining clips 46, 48 must be formed using a material which prevents corrosion at this critical connection point. In the present example, stainless steel is used for forming the retaining clips 46, 48 and the sides/ flanges thereof. The dimensions of 8mm (depth), 6mm (width) and 1.5mm thickness given above are the dimensions of the retaining clips in the present embodiment. However, other dimensions may also be used to achieve the invention. For example, the aforementioned measurements may have a tolerance of +/-5%.

[0066] The thermal break 40' in the present example comprises 26mm x 3mm glass reinforced polyamide (GRP), although it is to be appreciated that there is some tolerance in these measurements of approximately +/-10% such that other dimensions may be used if required in the particular glazing assembly being formed. In the present embodiment, the thermal break 40' is secured in each respective channel 52, 56 by using a continuous mechanical crimping technique to create a strong frictional joint between the GRP thermal break 40' and the flanges of the steel retaining clip 46, 48. In the present example, the mechanical crimping connection is stronger than the GRP tensile (20MPa) and shear strengths (24 MPa). In the present embodiment, no other materials are used to further secure the thermal break 40' in the channels before, during or after the mechanical crimping process. The provision of an integral thermal break 40' in the core 10' of the glazing assembly provides a substantial improvement in thermal efficiency of the glazing assembly by vastly reducing or eliminating thermal transfer through the thermally conductive core between the warmer, internally positioned regions and the colder, externally positioned regions of the glazing assembly. In contrast, the "non-broken" cores of prior art arrangements, such as that shown in Figure 1, do not have an integral thermal break in the core and are therefore not able to prevent or reduce thermal transfer through the core to the extent that the present invention can.

[0067] The thermal break 40' further comprises a silicone outer layer 62. The silicone outer layer 62' is inserted in a gap or break made in the lead alloy weathering extrusion sheath 42' to provide a thermal break in the sheathing material by sealing the two cut edges of the weathering extrusion sheath 42' together. The silicone outer layer 62 provides several technical advantages. One advantage is that the silicone outer layer 62 mitigates the high thermal transmission properties associated with traditional lead weathering extrusions which causes the inside of the glazing assembly 10' to become colder due to heat transfer when the glazing assembly 10' is exposed to cold air post-installation. Thus, the silicone outer layer 62 provides a further means, in addition to the GRP thermal break in the core of the body portion 10a', of insulating the glazing assembly by minimizing or at least substantially preventing heat transfer through the lead weathering extrusion 42' over the first component 10a and into the second component 10b of the body portion 10'. By cutting or breaking the sheath 42' and inserting a thermal break 62 in that cut region, thermal transfer through the sheath 42' between the warmer, internally positioned regions and the colder, externally positioned regions of the glazing assembly is significantly reduced or even eliminated, thus markedly improving thermal efficiency of embodiments of glazing arrangement in accordance with the present invention. In other words, the regions of the glazing assembly positioned within the confines of the building in which the assembly is fitted are warmer than the regions of the glazing assembly which are on the external facing surfaces of the glazing assembly, due to the thermal break providing a thermal barrier between the internally positioned regions of the glazing arrangement and the externally positioned regions of the glazing arrangement.

[0068] The glazing panels are further retained in the glazing assembly by a glazing stop 60 which engages the glazing panels 28, 38 and the body portion 10 of the glazing assembly 1, an example of which shown in Figure 3 and described in more detail in GB190909177 A. In the present embodiment, the glazing stop 60 comprises an extruded brass retaining clip. The glazing stop 60 is typically used in glazing arrangements having pitches over 60°, but can of course be applied to any glazing arrangement at any pitch, if required.

[0069] By arranging the thermal break 40' and the first and second components 10'a, 10'b of the body portion 10' so that they are connected to one another to form the body portion 10', thermal conductivity of the body portion 10' of the present invention is significantly reduced as compared to the known body portions which typically comprise metals such as steel or aluminium throughout which transfer thermal energy relatively readily throughout the body portion. This results in the glazing assembly of the present invention having a much lower thermal conductivity rating and thus is significantly more thermally efficient as compared to known glazing assemblies.

[0070] In addition to the thermal efficiency benefits, by replacing a part of the body portion with the thermal break, which in the present example, is GRP, the weight of the body portion is significantly reduced as compared to a body portion which comprises only metal (and no thermal break). This reduces the overall weight of the glazing assembly. This is particularly beneficial in patent glazing arrangements which form part or all of a roof structure because the thermal break can contribute to a reduction in the overall weight of the glazing assembly without reducing the strength of the glazing assembly because the thermal break contributes to the structural integrity of the body portion.

[0071] A method of producing a glazing assembly in accordance with the present invention is described, schematically, by way of example, as follows. The first and second components of the body portion are formed by an extrusion process which forces molten steel, in the present example, S235J mild carbon steel, through dies, each die having a shape which corresponds to the first and second components 10a', 10b' of the body portion 10b, respectively, to create the extruded first and second components of the body portion 10'. The extruded first component 10a' of the body portion 10' comprises an elongate, generally tubular component 18' depending from which is a stem 12'. At a distal end 50 of the stem 12', a channel 52 is defined during the extrusion process by creation of two spaced apart, parallel flanges depending from the distal end 50 of the stem 12'. The extruded second component 10b of the body portion 10' comprises an elongate, generally rectangular component 10b' having three spaced apart channels 30', 56, 30' each defined by two flanges extending upwardly from the inner-facing surface 22a', 22b' of the second component 10b'. After extrusion, the first and second components 10a', 10b' of the body portion are aligned such that the channel 52 at the distal end 50 of the stem 12' of the first component 10a' is aligned with a corresponding channel 56 located centrally on the inner facing surface 22a', 22b' of the second component lOb'. In the present example, the dimensions of the channel defined by the two flanges extending upwardly from the inner-facing surface are 8mm (depth), 6mm (width) and 1.5mm thickness. The channels 30' 56, 30' are each laser welded into position on the second component 10b' of the body portion 10'.

[0072] A lead weathering extrusion 42' is applied as a sheath around the core of the body portion 10' and the channels 52, 56 on each of the first and second components 10a', 10b' of the stem 12' are pushed into the lead weathering extrusion sheath 42'. A part of the lead weathering extrusion sheath 42' is cut on either side of the stem portion of the sheath 42' adjacent the underlying core stem 12'.

[0073] A pre-formed glass reinforced polyamide (GRP) thermal break 40' having dimensions of 26mm x 3mm glass reinforced polyamide in the present example, is positioned within each channel 52, 56 after which the flanges defining the sides of each channel 52, 56 are mechanically crimped against the thermal break 40', thus securing the thermal break 40' between the first and second components 10a', 10b' of the body portion 10' to provide a single piece stem 12' and body portion 10'. In the present example, the mechanical crimping connection is stronger than the GRP tensile (20MPa) and shear strengths (24 MPa).

[0074] After positioning and securing the GRP thermal break between the first and second components 10a', 10b' of the body portion 10', the cut or gap in the weather extrusion sheath 42' is aligned with the GRP thermal break 40' in the core of the body portion 10'. The gap in the sheath 42' is filled and sealed with silicone to form a silicone outer layer 62' in the region of the sheath 42' positioned externally of the body portion core. The silicone outer layer 62' provides a thermal break in the sheath 42' by virtue of the low thermal conductivity of the silicone. It will therefore be appreciated that the silicone example of the present embodiment may, in other embodiments, be substituted by another material to form the thermal break in the sheath 42'. By sealing the silicone outer layer 62' with the remainder of the lead alloy weathering extrusion sheath 42', the body portion 10' remains provided as a single part component, with the benefit of an integrated weathering system provided by the weather-resistant properties of the lead alloy that forms the extrusion sheath 42' and its integral silicone thermal break 62. This is in contrast to the prior art arrangements in which the glazing bar component is formed of more than one part, for example, a glazing mounting portion or bar and a cap which is attachable to the mounting portion/ bar. It is to be appreciated that other weather-resistant materials apart from lead may be used in one or more embodiments of the invention.

[0075] The first and second glazing panels 28', 38' are spaced apart and contained within a sealed glazing unit as shown in Figure 4. The sealed glazing unit 39 is mounted into the glazing assembly frame such that an edge of the first glazing panel 28' is on top of the ribs 26a, 26b on one side 14 of the second component 10b of the body portion 10', and the second glazing panel 38' is mounted such that it underlies and is in contact with the flange 44' of the weathering extrusion 42'. As shown in Figures 3 and 4, a further sealed glazing unit is mounted into the glazing assembly on a second side 16 of the second component 10b of the body portion 10' such that an edge of the first glazing panel 28' of the further sealed glazing unit is on top of the ribs on the second side 16 and the second glazing panel underlies and is in contact with the flange 44' of the weathering extrusion 42' on a second side of the stem 12.

[0076] Embodiments of glazing assembly according to the present invention provide a number of benefits over known glazing arrangements. As explained above, embodiments of glazing assembly according to the present invention are formed as a single part component that has a sheath, and that has a thermal break component mounted within the core. Accordingly, no fixing screws or similar fasteners are required to hold components of the glazing assembly together.

[0077] In addition to the aforementioned weathering protection benefits provided by the thermally broken weathering sheath 42' of the present invention, use of a sheath in accordance with embodiments of the present invention eliminates the need to use gaskets as part of the weathering protection for the glazing assembly and thus embodiments of the present invention provide a thermally broken glazing arrangement which is not reliant on gaskets to remain watertight. The present invention therefore provides a novel glazing assembly that is a sheathed thermally broken glazing assembly, suitable for use in a patent glazing arrangement, which has improved thermal efficiency and weatherability as compared to known arrangements, whilst still retaining the traditional aesthetic appeal required for embodiments of this invention, such as those used in older properties where a more traditional look is required.

[0078] Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of them mean "including but not limited to", and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0079] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0080] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

Claims

CLAIMS1. A glazing assembly comprising a frame, the frame comprising a body portion for receiving and supporting at least one glazing panel; the body portion comprising a first component, a second component; the first component and the second component being separate to one another; wherein at least a portion of the first component is configured to be positioned on the exterior of a building; and at least a portion of the second component is configured to be positioned on the interior of a building; and wherein the first component and the second component are connected together with a spacer component to form a substantially continuous body portion, and, wherein the spacer component comprises a material having a lower thermal conductivity than the first component and/or the second component of the body portion.
2. A glazing assembly as claimed in claim 1, wherein the spacer component comprises polyamide.
3. A glazing assembly as claimed in claim 2, wherein the spacer component comprises glass reinforced polyamide.
A glazing assembly as claimed in any preceding claim, wherein the first component of the body portion comprises a stem.
5. A glazing assembly as claimed in claim 4, wherein the spacer component is substantially collinear with respect to the stem of the first component of the body portion.
6. A glazing assembly as claimed in any preceding claim, wherein the spacer component is secured to each of the first component and second component of the body portion using mechanical crimping.
A glazing assembly as claimed in any preceding claim, wherein the spacer component comprises a silicone layer, optionally wherein the silicone layer defines at least a part of an external surface of the spacer component.
8. A glazing assembly as claimed in any preceding claim, wherein the body portion comprises a core, optionally wherein the core comprises steel, optionally stainless steel.
9. A glazing assembly as claimed in claim 8, wherein when the core comprises stainless steel, a percentage elongation of the core is between 20% and 28%.
10. A glazing assembly as claimed in claim 8 or claim 9, wherein the body portion comprises a sheath that surrounds the core.
11. A glazing assembly as claimed in claim 10, wherein the sheath comprises a lead alloy.
12. A glazing assembly as claimed in claim 11, wherein the sheath comprises 99.5% lead and 0.5% antimony.
13. A glazing assembly as claimed in any preceding claim, further comprising a barrier portion configured to engage at least a part of the body portion.
14. A glazing assembly as claimed in claim 13, wherein the barrier portion comprises lead.
15. A glazing assembly as claimed in claim 14, wherein the barrier portion comprises a lead alloy comprising 0.3% antimony.
16. A glazing assembly as claimed in any preceding claim, further comprising at least one glazing panel.
17. A glazing assembly as claimed in claim 16, when dependent on any of claims 13 to 15, wherein at least a part of the barrier portion is configured to overlie a part of the at least one glazing panel.
18. A glazing assembly as claimed in any preceding claim, further comprising one or more retaining members for retaining one or more glazing panels in the glazing assembly.
19. A method of producing a glazing assembly as defined in any preceding claim.