GB2571838A

GB2571838A - Secondary glazing for sash-type windows

Info

Publication number: GB2571838A
Application number: GB1903135.0A
Authority: GB
Inventors: Cooke Bernard
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-03-09
Filing date: 2019-03-08
Publication date: 2019-09-11
Anticipated expiration: 2039-03-08
Also published as: GB2571838B; GB201803793D0; GB201903135D0; GB2571777A

Abstract

A staff bead 70 including a magnetic material for allowing magnetic retrofitting of a secondary glazing panel assembly 140. The bead may be entirely magnetic or include a magnetic portion attached to the surface, in a channel or contained internally, and the bead may take the appearance of an existing staff bead. Also claimed is a sash window including a secondary glazing panel assembly and a method of installing secondary glazing using magnetic means. The glazing assembly may include a panel 142 having magnets 144 or a magnetic strip at its edges, which may be recessed or rebated into the panel. There may be further magnets 154 for allowing attachment of additional secondary panels for increased insulation. The assembly 140 may include a U-shaped channel 146 at its edge having a complementary profile to the staff bead, and concealing the magnetic means.

Description

Secondary glazing for sash-type windows

This invention relates to secondary glazing for sash-type windows, and methods for installing secondary glazing in a sash-type window.

Many buildings, in particular old buildings, feature sash-type windows. The term ‘sash-type window’ is a well-known term in the art and, as used hereinafter, refers to a window assembly comprising first and second (and possible further) sashes, each of which typically comprises one or more pane of glass, held in a frame, wherein the sashes are offset from one another. In some sash-type windows, the sashes may be slid relative to each other. Typically the direction of sliding is substantially vertical, however horizontally sliding sash-type windows are also possible.

A drawback associated with sash-type windows is that they are traditionally single glazed, i.e. with the window installed in the wall of a room, in the closed configuration of the window only a single pane of glass separates the inside of the room from the outside of the room. Single glazing is undesirable as a single pane of glass provides poor heat and noise insulation, for example compared with double or triple glazing. In addition to this, sash-type windows may allow draughts of air to pass around the edges of the sashes, which also reduces heat and noise insulation.

A known prior art method of overcoming these problems is the practise of installing secondary glazing. This is a practise wherein one or more pane of glass or transparent plastics material (commonly termed a secondary glazing panel) is added to the inside of a sash-type window, usually attached to the frame surrounding the sashes. However, prior art methods of installing secondary glazing have drawbacks associated with them.

For example, in prior art methods of installing secondary glazing, the secondary glazing may be provided within a frame, said frame being attached to the frame surrounding the sashes by, for example, glue, nails, screws or other attachment means. However, the secondary glazing significantly alters the visual appearance of the window. For some sash-type windows there may be insufficient space on the frame surrounding the sashes to affix the secondary glazing frame. In addition, the secondary glazing may make it difficult to access fully the window assembly, for example for the purposes of cleaning and maintenance.

It is known to provide strips of magnetic material on the frame surrounding the sashes and for a secondary glazing panel with magnets arranged perimetrically to be magnetically attached to the strips of magnetic material. However, in this situation the secondary glazing panel must naturally be considerably larger than the sashes in the window assembly to which secondary glazing is to be applied. This significantly alters the visual appearance of the window. For some sash-type windows there may be insufficient space on the frame surrounding the sashes to affix strips of magnetic material. Additionally, where window components (e.g. staff beads) project past the plane of the frame of the window assembly, these must be planed or shaved down to avoid obstructing the secondary glazing panel. This further alters the visual appearance of the window.

If the window assembly includes a shutter assembly, this may be rendered inoperable by the presence of secondary glazing attached using prior art methods, reducing the functionality of the sash-type window.

Where sash-type windows are present in old or historic buildings (e.g. listed buildings) it is generally desirable to minimise the impact of adding secondary glazing. In addition, local building rules or regulations may preclude the installation of secondary glazing if it cannot be done in a way which substantially maintains the visual appearance of the original sash-type window. It is therefore desirable to provide a method of installing secondary glazing wherein the secondary glazing has the minimum possible effect on the visual appearance of the sash-type window.

In many old sash-type windows the original staff beads have been damaged or broken over the years (for example, when sash cords have been renewed) and may have been replaced by new ones. Alternatively, they may have been replaced by new staff beads to incorporate weather strips. There is often, therefore, little historic merit to the staff beads found today in old sash-type windows. Consequently, the staff bead represents a component of the sash-type window that can be modified or replaced to install secondary glazing without detriment to the original window.

In accordance with a first aspect of the present invention there is provided a staff bead comprising a magnet and/or magnetic material.

The staff bead could be exclusively formed of a magnet or magnetic material.

The staff bead could comprise a magnet and/or magnetic material portion attached to a non-magnetic portion.

The magnet and/or magnetic material could be located on an outer surface of the staff bead.

The magnet and/or magnetic material could be contained internally within the staff bead.

The magnet and/or magnetic material could be located in a channel in the staff bead.

The staff bead could be shaped to be capable of engaging with the periphery (or connecting element) of a secondary glazing panel; and optionally wherein when engaged, the combined profile of the shaped staff bead and periphery (or connecting element) of the secondary glazing panel, may resemble a conventional/traditional staff bead. In this way, by for example making a recessed or docking area, the shaped staff bead is made ready to receive a secondary glazing panel. When the secondary panel is engaged (e.g. magnetically docked) the net visual effect may resemble a conventional/traditional staff bead. For example, when engaged/docked, the combined profile is lower than the sum of the profiles of the individual components. For example, with reference to Figure 17, it can be seen that the profile (e.g. cross section) of the shaped staff bead (70) together with the shaped element (146) gives together a profile that is reminiscent of a conventional/traditional staff bead (e.g. it resembles Figure 3). In this way the traditional look of the window as a whole can be preserved, and indeed the pane of the secondary glazing is less likely to get damaged if it is arranged to be recessed in this way.

In accordance with a second aspect of the present invention there is provided a kit for a sash-type window comprising:

a staff bead as set out above; and a secondary glazing panel comprising a magnet and/or magnetic material, wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.

In accordance with a third aspect of the present invention there is provided a sashtype window comprising:

a staff bead as set out above; and a secondary glazing panel comprising a magnet or magnetic material at a point on its periphery, wherein the magnet or magnetic material of the glazing panel is magnetically attached to the magnet and/or magnetic material of the staff bead.

The skilled person in the art would appreciate that for magnetic attachment, at least one of the staff bead and glazing panel would comprise a magnet. In the case that both staff bead and glazing panel comprise a magnet, these could be arranged to cooperate to produce a net attractive force. It is contemplated, that in the situation that both the staff bead and glazing panel comprise magnetic materials a bridging magnet could be employed to provide an attractive force. It is also contemplated that the staff bead and glazing panel may comprise both magnets and magnetic materials in any reasonable way to produce a net attractive force needed to hold the two elements together.

The panel could comprise top and bottom edges connected by a pair of lateral edges, and the panel could comprise at least one magnet and/or magnetic material on each of the lateral edges.

The panel could comprise at least one magnet and/or magnetic material on the top and bottom edges.

The panel could comprise a plurality of magnets and/or magnetic material on the lateral edges.

The panel could comprise a plurality of magnets and/or magnetic material on the top and bottom edges.

At least one magnet and/or magnetic material could be attached to a planar surface of the panel.

At least one magnet and/or magnetic material could be attached to an edge surface of the panel.

At least one magnet and/or magnetic material could be rebated into the secondary glazing panel.

A magnet and/or magnetic material could be attached to a planar surface of the panel

A magnet and/or magnetic material could be attached to an edge surface of the panel

The kit or sash-type window could further comprise a connecting element arranged to fit over an edge of the panel.

The connecting element could be substantially U-shaped.

The connecting element could contact both planar surfaces of the secondary glazing panel.

The connecting element could have a surface dimensioned to engage with the staff bead.

The connecting element could have a surface dimensioned to replicate the appearance of a conventional/traditional staff bead.

The connecting element could comprise a magnet and/or magnetic material.

The kit or sash-type window could comprise a further secondary glazing panel comprising a magnet and/or magnetic material at a point on its periphery, and the magnet and/or magnetic material of the further secondary glazing panel could be magnetically attached to the magnet and/or magnetic material of the first secondary glazing panel or the connecting element, or vice versa. The further secondary glazing panel could lie in the same plane as the first secondary glazing panel, or it could be stacked on top of the first secondary glazing panel to provide triple glazing. The kit or sash-type window could equally comprise more than two secondary glazing panels.

Where the kit or sash-type window comprises two or more secondary glazing panels to cover the full extent of the window (e.g. two panels corresponding in size and shape to the first and second sashes, and abutting along a line corresponding to the line where the sashes meet), the secondary glazing panels (or connecting elements) could comprise at least one magnet and/or magnetic material on the edges where they meet, to attach the panels together as further described below.

It is contemplated that a kit for a sash-type window, or a sash-type window, could comprise:

a staff bead comprising a magnet and/or magnetic material;

a secondary glazing panel comprising a magnet and/or magnetic material; wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead; and further wherein the secondary glazing panel comprises a connecting element arranged to fit on an edge of the panel;

and wherein the connecting element has a surface dimensioned to engage with the staff bead, and wherein the connecting element may have a surface dimensioned to replicate the appearance of a conventional/traditional staff bead when attached.

In accordance with a fourth aspect of the present invention there is provided a secondary glazing panel comprising a magnet and/or magnetic material at a point on its periphery, wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to a magnet and/or magnetic material located on or within a staff bead, optionally the staff bead is a staff bead of the first aspect of the invention.

In an embodiment, the secondary glazing panel, further comprises a connecting element arranged to fit on an edge of the secondary glazing panel;

and wherein the connecting element has a surface dimensioned to engage with the staff bead, and/or wherein the connecting element may have a surface dimensioned to replicate the appearance of a conventional/traditional staff bead when engaged.

In an embodiment, the connecting element of the secondary glazing panel comprises the magnet and/or magnetic material.

In accordance with a fifth aspect of the present invention there is provided a method of installing secondary glazing on a sash-type window, the sash-type window comprising an outer box frame, one or more sashes within the box frame, and a staff bead provided around an interior of the box frame, the method comprising the steps of:

removing the staff bead;

replacing the staff bead with staff bead comprising a magnet and/or magnetic material; and attaching a secondary glazing panel to the staff bead, wherein the secondary glazing panel comprises a magnet and/or magnetic material at a point on its periphery, and wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.

In accordance with a sixth aspect of the present invention there is provided a method of installing secondary glazing on a sash-type window, the sash-type window comprising an outer box frame, one or more sashes within the box frame, and a staff bead provided around an interior of the box frame, the method comprising the steps of:

retrofitting the staff bead with a magnet and/or magnetic material; and attaching a secondary glazing panel to the staff bead, wherein the secondary glazing panel comprises a magnet or magnetic material at a point on its periphery and wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.

In accordance with a seventh aspect of the present invention there is provided a method of installing secondary glazing on a sash-type window, the method comprising the steps of:

replacing the staff bead with a staff bead as mentioned hereinabove; and attaching a secondary glazing panel as mentioned hereinabove to the staff bead, wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.

The invention will now be further described by way of non-limiting example with reference to the accompanying drawings, in which:

Fig. 1 schematically shows a front view of a sash-type window;

Fig. 2 schematically shows a top-down cross-sectional view of the sash-type window of Fig. 1;

Fig. 3 schematically shows a cross-sectional view of a first staff bead;

Fig. 4 schematically shows a cross-sectional view of a second staff bead;

Fig. 5 schematically shows a cross-sectional view of a first staff bead in accordance with the present invention;

Fig. 6 schematically shows a cross-sectional view of a second staff bead in accordance with the present invention;

Fig. 7 schematically shows a cross-sectional view of a third staff bead in accordance with the present invention;

Fig. 8 schematically shows a cross-sectional view of a fourth staff bead in accordance with the present invention;

Fig. 9 schematically shows a cross-sectional view of a fifth staff bead in accordance with the present invention;

Fig. 10 schematically shows a front view of a secondary glazing panel suitable for use in the present invention;

Fig. 11 schematically shows a partial cross-sectional view of the secondary glazing panel of Fig. 10;

Fig. 12 schematically shows a partial cross-sectional view of a further exemplary secondary glazing panel suitable for use in the present invention;

Fig. 13 schematically shows a partial cross-sectional view of a further exemplary secondary glazing panel suitable for use in the present invention;

Fig. 14 schematically shows a front view of a secondary glazing panel suitable for use in the present invention;

Fig. 15 schematically shows a cross-sectional view of the secondary glazing panel of Fig. 14;

Fig. 16 schematically shows a partial cross-sectional view of a secondary glazing panel assembly suitable for use in the present invention; and

Fig. 17 schematically shows a partial cross-sectional view of the secondary glazing panel assembly of Fig. 16 installed on the staff bead 70 of Fig. 7.

Fig. 1 schematically shows a front view of a sash-type window 10. The sash-type window 10 comprises an outer box frame 12. The box frame 12 encloses a first sash 14 and a second sash 16. The first sash 14 contains several panes of glass (three indicated at reference numeral 20). The panes of glass are held in place by glazing bars 22. The second sash contains several panes of glass (three indicated at reference numeral 24). The panes of glass are held in place by glazing bars 26.

The first and second sashes are offset from one another within the box frame 12. In the window shown in Fig. 1 the first sash is an outer sash (i.e. where the sash-type window is installed in a wall of a room, the first sash is located towards the outside of the room), and the second sash is an inner sash (i.e. where the sash-type window is installed in a wall of a room, the second sash is located towards the inside of the room), although the inner and outer positions could equally be reversed.

The first sash is a fixed sash, i.e. it is permanently held in the upper portion of the box frame 12 in the position shown in Fig. 1. The second sash is a sliding sash, i.e. the second sash is arranged to move within the box frame 12. The second sash 16 can be lifted and, due to the offset described above, the second sash may move past the first sash until both the first and second sashes are located in the upper portion of the box frame 12.

The box frame 12 contains a weight and pulley system, or a spring balance system, connected to the second sash. The weight and pulley system, or the spring balance system, acts to counterbalance the weight of the second sash and make it easier to lift, as is well-known in the art. However, while Fig. 1 shows a sash-type window with a fixed sash and a sliding sash, many sash-type windows exist in which both sashes are fixed sashes, or in which both sashes are sliding sashes. Apart from the presence or absence of a weight and pulley system, or spring balance system, the construction of such windows is substantially the same as described with respect to Fig. 1.

A staff bead 18 runs around an interior surface of the box frame 12, as is well-known in the art.

Fig. 2 schematically shows a top-down cross-sectional view of the sash-type window 10 of Fig. 1. Like reference numerals have been retained as appropriate. In this view it can be seen that the first (outer) sash 14 is separated from the second (inner) sash 16 by a parting bead 28. The cross-sectional shape of a typical staff bead 18 can also be seen, although other shapes are possible. As is well known in the art, the staff bead 18 is typically a continuous structure running around the entire interior surface of the box frame 12, i.e. along both vertical sides and along the top and bottom. In some examples, however, the staff bead may not be present around the entire interior surface of the box frame.

Fig. 3 schematically shows a cross-sectional view of a first staff bead 30. Staff beads are generally constructed of timber.

The staff bead 30 comprises a first edge 32 which abuts the box frame of the sashtype window in use. A second, adjacent edge 34 abuts the second (inner) sash of the sash-type window in use. A third, curved edge 36 projects into the interior of the room when the sash-type window is installed in a wall of a room. The third edge 36 curves into a fourth edge 38. Nothing abuts this fourth edge 38 in use.

Fig. 4 schematically shows a cross-sectional view of a second staff bead 40. Similarly to the staff bead shown in Fig. 3, the staff bead 40 comprises a first edge 42 which abuts the box frame of the sash-type window in use. A second, adjacent edge 44 abuts the second (inner) sash of the sash-type window in use. A third, curved edge 46 projects into the interior of the room when the sash-type window is installed in a wall of a room. The third edge 46 curves into a fourth edge 48. Nothing abuts this fourth edge 48 in use.

However, the staff bead 40 of Fig. 4 further comprises a channel 45 cut into the second edge 44 of the staff bead 40. This channel 45 is suitable for holding a weather strip (not shown). As the second edge 44 abuts the second (inner) sash of the sash-type window, a weather strip located in the channel 45 may act to reduce draughts from flowing between the second (inner) sash and the staff bead 40, particularly where said sash is a sliding sash.

Fig. 5 schematically shows a cross-sectional view of a first staff bead 50 in accordance with the present invention. The staff bead is formed of a magnetic material as indicated at M1. Otherwise, the staff bead 50 has all the other features of the existing staff beads described above with respect to Figs. 3 and 4, including a first edge 52 that abuts the box frame of the sash-type window in use, a second, adjacent edge 54 that abuts the second (inner) sash of the sash-type window in use, a third, curved edge 56 that projects into the interior of the room when the sash-type window is installed in a wall of a room. As in existing staff beads, the third edge 56 curves into a fourth edge 58. The staff bead 50 therefore replicates the visual appearance of existing staff beads which may be present in existing sash-type windows.

A channel 55 may or may not be present as desired. If the channel 55 is present, then the staff bead 50 replicates the shape of the staff bead shown in Fig. 4. If the channel 55 is absent, then the staff bead 50 replicates the shape of the staff bead shown in Fig. 3

To aid attachment of the staff bead 50 to the box frame of a sash-type window, one or more through-hole may be formed in the staff bead 50. The through hole could pass from the fourth edge 58 to the first edge 52, and could be dimensioned so that attachment means (e.g. screws or nails) could pass from the fourth edge 58 to the first edge 52 and into the box frame which the first edge 52 abuts in use. Alternatively, said hole(s) could be cut or drilled into the staff bead 50 after fabrication.

Fig. 6 schematically shows a cross-sectional view of a second staff bead 60 in accordance with the present invention. The staff bead 60 comprises a magnetic material M2. A surface 66 of the magnetic material M2 is shaped to replicate the visual appearance of a staff bead third edge (see above). The staff bead 60 further comprises a first edge 62 that abuts the box frame of the sash-type window in use and a second, adjacent edge 64 that abuts the second (inner) sash of the sash-type window in use. As in existing staff beads, the surface 66 replicating a third edge curves into a fourth edge 68. The staff bead 60 therefore replicates the visual appearance of existing staff beads which may be present in existing sash-type windows. The staff bead 60 further comprises a channel 65 cut into a second edge of the staff bead 60. This channel 65 is suitable for holding a weather strip (see description with respect to Fig. 4 above). The channel 65 may be omitted if no weather strip is required.

It will be readily appreciated that the staff bead 60 may be entirely fabricated ‘from scratch’ using modern building materials. In this case, the staff bead of a sash-type window to which secondary glazing is to be installed may simply be removed and replaced wholesale.

Alternatively, the existing staff beads of a sash-type window to which secondary glazing is to be installed may be modified to result in the staff bead 60. For example, the staff bead described above with respect to Fig. 3 or 4 may be removed from a sash-type window, the third edge may be cut away (as shown by the shaded area in Fig. 6) and replaced with a magnetic material M2. The staff bead can then be returned to its original position on the sash-type window.

Alternatively, a magnetic material may be attached, or otherwise added, to the third edge 36 or 46 of a staff bead as described above with respect to Fig. 3 or 4, thereby increasing the amount that the third, curved edge 36 or 46 projects into the interior of the room when the sash-type window is installed in a wall of a room.

To aid attachment of the staff bead 60 to the box frame of a sash-type window, one or more through-hole may be formed in the staff bead 60. The through hole could pass from the fourth edge 68 to the first edge 62, and could be dimensioned so that attachment means (e.g. screws or nails) could pass from the fourth edge 68 to the first edge 62 and into the box frame which the first edge 62 abuts in use. Alternatively, said hole(s) could be cut or drilled into the staff bead 60 after fabrication.

Fig. 7 schematically shows a cross-sectional view of a third staff bead 70 in accordance with the present invention. The staff bead 70 is constructed of a magnetic material M3. Similarly to the staff beads shown in Figs. 3 and 4, the staff bead 70 comprises a first edge 72 which abuts the box frame of the sash-type window in use. A second, adjacent edge 74 abuts the second (inner) sash of the sash-type window in use. A third, curved edge 76 projects into the interior of the room when the sash-type window is installed in a wall of a room. The third edge 76 curves into a fourth edge 78. Nothing abuts this fourth edge 78 in use.

The overall shape of the staff bead 70 is similar to that of existing staff beads. However, the third edge 76 is recessed into the staff bead 70 as shown. This reveals an inner edge 79. The third edge 76, in conjunction with the inner edge 79, provides a ‘bed’ or ‘frame’ in which a secondary glazing panel may be located. This will be described in more detail below.

Fig. 8 schematically shows a cross-sectional view of a fourth staff bead 80 in accordance with the present invention. The staff bead 80 is similar to that shown in Fig. 7. The staff bead 80 comprises a first edge 82 which abuts the box frame of the sash-type window in use. A second, adjacent edge 84 abuts the second (inner) sash of the sash-type window in use. A third, curved edge 86 projects into the interior of the room when the sash-type window is installed in a wall of a room. The third edge 86 curves into a fourth edge 88. The third edge 86 is recessed into the staff bead 80 as shown. This reveals an inner edge 89. The third edge 86, in conjunction with the inner edge 89, provides a ‘bed’ or ‘frame’ in which a secondary glazing panel may be located. This will be described in more detail below.

However, instead of the staff bead 80 being constructed with a solid cross section it is constructed with a hollow cross section. The hollow may be wholly contained within the cross section of the staff bead, as shown in Fig. 8, or may extend to one or more edges of the staff bead, thus forming a channel. If the staff bead 80 is constructed of a magnetic material, the hollow cross section will reduce the amount of magnetic material that is required to produce the staff bead. Alternatively, if the staff bead 80 is constructed of a non-magnetic material (e.g. timber) the hollow may contain a magnetic material M4 in the hollow or channel within the staff bead 80. Alternatively, the staff bead 80 may be constructed or formed around the magnetic material M4.

It will be readily appreciated that the staff bead 80 may be entirely fabricated ‘from scratch’ using modem building materials. In this case, the staff bead of a sash-type window to which secondary glazing is to be installed may simply be removed and replaced wholesale.

Alternatively, the existing staff beads of a sash-type window to which secondary glazing is to be installed may be modified to result in the staff bead 80. For example, the staff bead may be removed from a sash-type window, a hollow or channel may be cut into the staff bead and a magnetic material M4 inserted into said hollow or channel. The staff bead can then be returned to its original position on the sash-type window.

Fig. 9 schematically shows a cross-sectional view of a fifth staff bead 90 in accordance with the present invention. The staff bead 90 is similar to that shown in Figs. 7 and 8. The staff bead 90 comprises a first edge 92 which abuts the box frame of the sash-type window in use. A second, adjacent edge 94 abuts the second (inner) sash of the sash-type window in use. A third, curved edge 96 projects into the interior of the room when the sash-type window is installed in a wall of a room. The third edge 96 curves into a fourth edge 98. The third edge 96 is recessed into the staff bead 90 as shown. This reveals an inner edge 99. The third edge 96, in conjunction with the inner edge 99, provides a ‘bed’ or ‘frame’ in which a secondary glazing panel may be located. This will be described in more detail below.

However, instead of the staff bead 90 being constructed of a magnetic material, a first part A of the staff bead 90 is constructed of a non-magnetic material (e.g. timber) and a second part B, constructed of a magnetic material, is attached to the first part A. Part A and part B could be swopped around, such that part A is constructed of a magnetic material and Part B is constructed of a non-magnetic material.

It will be readily appreciated that the staff bead 90 may be entirely fabricated ‘from scratch’ using modern building materials. In this case, the staff bead of a sash-type window to which secondary glazing is to be installed may simply be removed and replaced wholesale.

Alternatively, the existing staff beads of a sash-type window to which secondary glazing is to be installed may be modified to result in the staff bead 60. For example, the staff bead may be removed from a sash-type window, the third edge may be cut away (as shown by the shaded area B in Fig. 9) and replaced with a magnetic material. The staff bead can then be returned to its original position on the sash-type window.

To aid attachment of each of the staff beads 70, 80, 90 to the box frame of a sashtype window, one or more through-hole may be formed in the staff bead 70, 80, 90. The through-hole could pass from the fourth edge 78, 88, 98 (or the inner edge 79,

89, 99) to the first edge 72, 82, 92, and could be dimensioned so that attachment means (e.g. screws or nails) could pass from the fourth edge 78, 88, 98 (or the inner edge 79, 89, 99) into the box frame which the first edge 72, 82, 92 abuts in use. Alternatively, said hole(s) could be cut or drilled into the staff bead 70, 80, 90 after fabrication.

Fig. 10 schematically shows a front view of a secondary glazing panel 100 suitable for use in the present invention. The secondary glazing panel 100 is preferably constructed of a lightweight transparent material, such as a plastics material. Plastics materials such as acrylic or polycarbonate are particularly useful, as these materials are also easily machined or drilled.

The secondary glazing panel 100 has magnetic strips attached around its perimeter (indicated by the shaded area 102). The magnetic strips are shown as being continuous in Fig. 10, however, depending on the magnetic attraction required they may be non-continuous. Non-magnetic strips may be substituted for part of the magnetic strips. The magnetic strip on a secondary glazing panel may also vary in thickness, width and magnetic strength. The magnets are preferably neodymium magnets, as these have been found to provide a sufficiently strong attaching force between the secondary glazing panel 100 and the staff beads.

Where more than one secondary glazing panel is employed to secondary glaze a sash-type window the magnetic strips attached to the lateral edges ofthe secondary glazing panel 100 will ideally be of sufficient strength to hold the weight of the secondary glazing panel 100, in order to allow the panel to be located at any height on the sash-type window as further described below.

Where more than one secondary glazing panel is employed to secondary glaze a sash-type window, the edge of a secondary glazing panel that abuts another secondary glazing panel will not be adjacent to the staff bead and therefore will not require a magnetic strip to attach it to the staff bead. Instead a magnet, magnetic strip, or magnetic material may be attached to, or rebated in to, the edge surface of the secondary glazing panel (or within the connecting element described further below) to attach it magnetically to another secondary glazing panel as further described below.

Fig. 11 schematically shows a partial cross-sectional view of the secondary glazing panel 100 of Fig. 10.

In this view it can be seen that a magnetic strip 104 is attached to one of the planar surfaces of the secondary glazing panel 100 at a point on its periphery. The magnetic strip 104 may be attached by any suitable means, e.g. gluing, screwing, etc.

Fig. 12 schematically shows a partial cross sectional view of a further exemplary secondary glazing panel 110 for use in the present invention. In this example, a magnetic strip 114 has been rebated into the secondary glazing panel 110 at a point on its periphery.

Fig. 13 schematically shows a partial cross sectional view of a further exemplary secondary glazing panel 120 for use in the present invention. In this example, a magnetic strip 124 has been rebated into the secondary glazing panel 120 at a point on its periphery, but slightly inset when compared to the example shown in Fig. 12.

Fig. 14 schematically shows a front view of a secondary glazing panel 130 suitable for use in the present invention. The secondary glazing panel 130 is preferably constructed of a lightweight transparent material, such as a plastics material. Plastics materials such as acrylic or polycarbonate are particularly useful, as these materials are also easily machined and drilled.

The secondary glazing panel 130 has a number of discrete magnets attached along its lateral edges and its top and bottom edges. Magnets attached along the lateral edges are indicated at reference numerals 132 and 134, and magnets attached along the top and bottom edges are indicated at reference numerals 136 and 138 respectively. Holes may be formed in the panel, into which the magnets may be inserted. Alternatively, holes may be drilled or cut into the panel after fabrication.

Any number of magnets may be used in practise, but where more than one panel is used to secondary glaze a sash-type window ideally the magnets along the lateral edges will be strong enough to support the weight of the secondary glazing panel 130 in order to allow the panel to be located at any height on the sash-type window as further described below according to the invention. In the limit a single magnet may be present on each side of the secondary glazing panel 130.

Fig. 15 schematically shows a cross-sectional view of the secondary glazing panel 130 of Fig. 14. Like reference numerals have been retained as appropriate.

In this view it can be seen that the magnets 132, 136 are set into the secondary glazing panel 130, e.g. by drilling holes into the panel and inserting magnets into the holes. In alternative embodiments the magnets could be attached to the face or edge of the secondary glazing panel 130 e.g. using adhesive.

Magnet 136 is shown set (or with magnetic attraction) at right angles to the magnets 132. Where two or more panels are used to secondary glaze a sash-type window the magnetic attraction provided by the magnet 136 serves to hold the panels together at the point where the panels meet. Where each panel comprises magnets set at right angles, these must be of opposite polarity for the magnetic attraction to work. Alternatively, one of the panels where the panels meet may comprise magnetic material in place of magnet 136.

While Fig. 15 shows a panel comprising a number of discrete magnets, the above technique may also be applied to panels comprising magnetic strips. Again, where the panels meet, the magnetic strips will need to be of opposite polarity for the magnetic attraction to work. Alternatively, one of the panels may comprise magnetic material in place of magnet 136.

Fig. 16 schematically shows a partial cross-sectional view of a secondary glazing panel assembly 140 suitable for use with the staff beads shown in Figs. 5, 6, 7, 8 and 9. The drawing shows a discrete magnet in accordance with the secondary glazing panel shown in Figs. 14 and 15 but could equally describe a secondary glazing panel in accordance with Figs. 10, 11, 12 and 13.

The secondary glazing panel assembly 140 comprises a secondary glazing panel 142 with a magnet 144 embedded in the secondary glazing panel 142 near its periphery. A U-shaped element 146 is attached along the edge of the secondary glazing panel 142. The U-shaped element 146 comprises an inner curved surface 148 and an outer curved surface 150.

The inner curved surface 148 is dimensioned so as to correspond in size and shape to the third surface of a staff bead (see surface 56, 66, 76, 86 and 96 in Figs. 5, 6, 7, 8 and 9). In the case of staff beads 70, 80 and 90 a lateral edge 152 of the Ushaped element 146 contacts the inner surface of the staff bead (see surfaces 79, 89 and 99 in Figs. 7, 8 and 9). In this way, the U-shaped element is located in the ‘bed’ or ‘frame’ described above, and so the secondary glazing panel 142 is maintained in a fixed position with respect to the window frame abutting the staff bead. The outer curved surface 150 replicates the shape of the original staff bead so that the sashtype window will retain its original visual appearance even after secondary glazing has been installed on it. Where the staff bead has previously been modified (e.g. repaired or replaced over the years) prior to secondary glazing being installed, the outer curved surface 150 may replicate the original, unmodified staff bead. In this way, the act of installing secondary glazing may serve a dual purpose by both improving the heat and sound insulation of the window, and at the same time restoring the appearance of the sash-type window.

The U-shaped element 146 also comprises a magnetic material 154 so that further secondary glazing panels (e.g. the secondary glazing panels shown in Figs. 10-15) may be ‘stacked’ on the first panel 142 e.g. to provide triple or quadruple glazing. As well as being capable of stacking, where two or more secondary glazing panels are used to cover the full extent of the window (e.g. two panels corresponding in size and shape to the first and second sashes, and abutting along a line corresponding to the line where the sashes meet), it may sometimes be desirable to move one panel to partially overlap another. For example, during summer months the gap revealed by moving one panel to an overlapping position can be used to provide an air flow into / out of the room.

Alternatively, the magnetic material 154 may be attached by glue or other suitable means to the secondary glazing panel, or rebated into the secondary glazing panel, and not form part of the U-shaped element. In these cases, the U-shaped element could be omitted and stacking or overlapping could still be achieved using multiple panels.

However, the magnetic material 154 may be omitted in some embodiments e.g. where stacking or overlapping of secondary glazing panels is not required, or where the configuration of magnets or magnetic strips provides sufficient magnetic strength to enable stacking or overlapping.

Fig. 17 schematically shows a partial cross-sectional view of the secondary glazing panel assembly 140 of Fig. 16 installed on the staff bead 70 of Fig. 7. Like reference numerals have been retained as appropriate.

It will further be appreciated by those skilled in the art that although the invention has been described by way of example with reference to the Figures above it is not so limited and that alternative embodiments could be constructed without departing from the scope of the invention as defined in the appended claims.

For example, a handle or pull-cord may be attached to, or embedded in, a secondary glazing panel. This is particularly useful for embodiments in which the secondary glazing panel lies flush with the surrounding staff bead in use. In these circumstances it may be difficult for a user to pry the panel out of the ‘bed’ or ‘frame’ as there will be little clearance for the user’s fingers. The handle (which could be a removable magnetic handle, utilising magnetic attraction between the handle and the secondary glazing panel) or pull-cord will facilitate removal of the secondary glazing panel.

As a further example, while rectangular first and second sashes are shown in the Figures, the invention is not limited to this, and can be applied to any shape of window assembly in practise. For example, it is not unusual for the uppermost sash to have an arched or semi-circular shape.

A layer of insulating material may be added, for example, to surface 54, 64, 74, 84 or 94 to reduce conduction of heat through the staff bead. This will be particularly useful where the staff bead is constructed of, or comprises, a material which is a good conductor of heat.

While the forgoing description makes reference to the addition of secondary glazing to a sash-type window the invention applies equally to the situation where a sashtype window is constructed from scratch.

While the foregoing description makes reference to secondary glazing being the installation of one or more secondary glazing panel generally in a single plane on a window assembly, the invention is not limited to a panel or panels in a single plane. Any number of stacked panels could be used in practise to provide, for example, triple or quadruple glazing, with enhanced heat and sound insulation being achieved through the use of a greater number of panels.

While first and second sashes are shown in the Figures, the invention is not limited to window assemblies having exactly two sashes. For example, the invention may be applied to window assemblies having more than two sashes.

Additionally, while the secondary glazing panels described above are transparent panels, in some circumstances it may be desirable to fit other panels, such as an insect screen or blackout panel, over a sash-type window. The present invention may be used to do this instead or as well.

Additional strips of material, comprising a magnet or magnetic strip, may be provided to be located in the recess in the staff beads shown in Figs. 7, 8 and 9 to restore the cross section of the staff bead to a traditional shape where a secondary glazing panel has been removed e.g. temporarily during the summer months.

While the staff beads described above have curved surfaces to replicate a traditional pattern, the invention may be applied to staff beads of any shape, e.g. staff beads having flat surfaces.

While the secondary glazing panels described above comprise magnetic strips or discrete magnets, the invention may be applied to a secondary glazing panel comprising a mix of both magnetic strips and discrete magnets.

While the secondary glazing panels described above comprise single planar sheets of e.g. plastics materials, the invention may be applied to secondary glazing panels comprising more than one planar sheet.

While the above embodiments have been described as having magnets disposed in the panel and a magnetic material in the staff bead, these could readily be swapped around (i.e. such that the staff bead comprises a magnet and the panel comprises a magnetic material). It is also contemplated in the case that both staff bead and glazing panel comprise a magnet, these could be arranged to cooperate to produce a net attractive force.

For example, the magnetic material could be a first material and the magnet could be a second material; wherein the first material is a first magnet having a first magnetic polarity (e.g. North); the second material is a second magnet having a second magnetic polarity (e.g. South); or a magnetic material;

and wherein the first and second materials are arranged to be attracted by magnetic force.

It is contemplated, that in the situation that both the staff bead and glazing panel comprise magnetic materials a bridging magnet could be employed to provide an attractive force. It is also contemplated that the staff bead and glazing panel may comprise both magnets and magnetic materials in any reasonable way to produce a net attractive force needed to hold the two elements together.

Claims

1. A staff bead comprising a magnet and/or magnetic material.

2. A staff bead according to claim 1, wherein the staff bead is exclusively formed of a magnet or magnetic material, or wherein the staff bead comprises a magnet and/or magnetic material portion attached to a non-magnetic portion; or wherein the magnet and/or magnetic material is located on an outer surface of the staff bead; and/or is contained internally within the staff bead; and/or is located in a channel in the staff bead.

3. A staff bead according to claim 1 or 2, wherein the staff bead is shaped to be capable of engaging with the periphery, or connecting element, of a secondary glazing panel; and optionally wherein when engaged, the combined profile of the shaped staff bead and periphery or connecting element of the secondary glazing panel resembles a conventional/traditional staff bead.

4. A kit for a sash-type window comprising:

a staff bead according to any one of claims 1 to 3; and a secondary glazing panel comprising a magnet and/or magnetic material, wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.

5. A sash-type window comprising:

a staff bead according to any of claims 1 to 3; and a secondary glazing panel comprising a magnet and/or magnetic material at a point on its periphery, wherein the magnet and/or magnetic material of the glazing panel is magnetically attached to the magnet and/or magnetic material of the staff bead.

6. A kit or sash-type window according to claim 4 or 5, wherein the panel comprises top and bottom edges connected by a pair of lateral edges, and wherein the panel comprises at least one magnet and/or magnetic material on each of the lateral edges.

7. A kit or sash-type window according to any one of claims 4 to 6, wherein the panel comprises at least one magnet and/or magnetic material on the top and bottom edges.

8. A kit or sash-type window according to any one of claims 4 or 7, wherein the panel comprises a plurality of magnets and/or magnetic materials on the lateral edges; and/or wherein the panel comprises a plurality of magnets and/or magnetic materials on the top and bottom edges.

9. A kit or sash-type window according to any of claims 4 to 8, wherein at least one magnet and/or magnetic material is attached to a planar surface of the panel.

10. A kit or sash-type window according to any of claims 4 to 9, wherein at least one magnet and/or magnetic material is attached to an edge surface of the panel.

11. A kit or sash-type window according to any of claims 4 to 10, wherein at least one magnet and/or magnetic material is rebated into the secondary glazing panel.

12. A kit or sash-type window according to any of claims 4 to 11, wherein the kit or sash-type window further comprises a further secondary glazing panel comprising a magnet and/or magnetic material at a point on its periphery, and wherein the magnet and/or magnetic material of the further secondary glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the secondary glazing panel.

13. A kit or sash-type window according to any of claims 4 to 12, further comprising a connecting element arranged to fit over an edge of the panel.

14. A kit or sash-type window according to claim 13, wherein the connecting element has a surface dimensioned to engage with the staff bead.

15. A kit or sash-type window according to claim 13 or 14, wherein the connecting element has a surface dimensioned to replicate the appearance of a staff bead.

16. A kit or sash-type window according to any one of claims 13 to 15, wherein the connecting element is substantially U-shaped.

17. A kit or sash-type window according to any one of claims 13 to 16, wherein the connecting element contacts both planar surfaces of the secondary glazing panel.

18. A kit or sash-type window according to any of claims 13 to 17, wherein the connecting element comprises a magnet and/or magnetic material.

19. A kit or sash-type window according to any one of claims 4 to 18, wherein the kit or sash-type window further comprises a further secondary glazing panel comprising a magnet and/or magnetic material at a point on its periphery, and wherein the magnet and/or magnetic material of the further secondary glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of, or within, the connecting element.

20. A kit for a sash-type window, or a sash-type window, comprising:

a staff bead comprising a magnet and/or magnetic material;

a secondary glazing panel comprising a magnet and/or magnetic material;

wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead; and further wherein the secondary glazing panel comprises a connecting element arranged to fit on an edge of the panel;

and wherein the connecting element has a surface dimensioned to engage with the staff bead, and wherein optionally the connecting element has a surface dimensioned to replicate the appearance of a conventional/traditional staff bead when attached.

21. A secondary glazing panel comprising a magnet and/or magnetic material at a point on its periphery, wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to a magnet and/or magnetic material located on or within a staff bead; and optionally the staff bead is a staff bead as defined in any one of claims 1 to 3.

22. A secondary glazing panel of claim 21, further comprising a connecting element arranged to fit on an edge of the secondary glazing panel;

and wherein the connecting element has a surface dimensioned to engage with the staff bead, and/or wherein the connecting element has a surface dimensioned to replicate the appearance of a conventional/traditional staff bead when engaged.

23. A secondary glazing panel of claim 21 or 22 wherein the connecting element comprises the magnet and/or magnetic material.

24. A method of installing secondary glazing on a sash-type window, the sashtype window comprising an outer box frame, one or more sashes within the box frame, and a staff bead provided around an interior of the box frame, the method comprising the steps of:

(i) replacing the staff bead with staff bead comprising a magnet and/or magnetic material; or retrofitting the staff bead with a magnet and/or magnetic material; and (ii) attaching a secondary glazing panel to the staff bead, wherein the secondary glazing panel comprises a magnet and/or magnetic material at a point on its periphery, wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.

25. A method of installing secondary glazing on a sash-type window, the method comprising the steps of:

replacing the staff bead with a staff bead as defined in any one of claims 1 to 20; and

5 attaching a secondary glazing panel as defined in any one of claims 1 to 23 to the staff bead; and wherein the magnet and/or magnetic material of the glazing panel is arranged for magnetic attachment to the magnet and/or magnetic material of the staff bead.