[0001] The present invention relates to cladding systems, for example roof or wall cladding
systems, including support bars which are mounted by brackets to a support structure,
cladding panels being secured to the support bars by means of further brackets.
[0002] In twin skin metal roof assemblies such as the Ashgrid® system, it is known to mount
a roofing bar on a rafter using a support bracket. Such a prior art support bracket,
indicated generally at 10 in Figure 2, is formed from a single piece of bent galvanised
steel sheet and comprises a generally flat body portion 12, and a mounting portion
14 which extends from a first end 12a of the body portion 12 generally perpendicular
thereto. The mounting portion 14 is provided with a plurality of apertures through
which fasteners such as screws or bolts may pass in order to fasten the mounting portion
14 onto a rafter. A second end 1 2b of the body portion 1 2 is provided with cut-outs
18 which permit it to engage with flange formations 20 on a channel section roofing
bar 16. The bracket 12 may be located at an appropriate position on the roofing bar
16 and twisted so that the cut outs 18 engage the flange formations 20 and lock the
support bracket 10 in position. Further brackets (not shown) may then be secured to
the roofing bar, by suitable fastening means, to support the cladding panels.
[0003] GB-A-2423097 discloses a modified support bracket with formations which slidingly engage flange
formations on the roofing bar, so that the bracket formations may be positioned longitudinally
of the roofing bar, by sliding them along the bar. This specification also discloses
that brackets for supporting the cladding panels may also be slidingly located on
the roofing bar.
[0004] Both of the above mentioned cladding systems use a support/roofing bar of channel
section, the channel opening towards the support structure, the support brackets between
the support bar and support structure extending within the side walls of the channel
section and the brackets for supporting the cladding panels being secured to the base
of the channel section.
[0005] While the systems used hitherto facilitate mounting and location of the support bar
relative to the brackets between the support bar and support structure, mounting and
location of the brackets between the support bar and cladding panels, which are normally
more frequent and require more accurate location to locate with the cladding panels,
is not so straight forward.
[0006] According to a first aspect of the invention, a cladding system includes a support
bar, the support bar being of channel section, having a base and a pair of side walls
extending to one side of the base, inwardly extending flange formations extending
along the edges of the side walls remote from the base; a plurality of first bracket
formations, the first bracket formations having a base formation adapted to be secured
to a support structure and a formation, spaced axially of the base formation, for
engagement of the channel section, so that the first brackets may be secured to the
channel section at longitudinally spaced locations, the first brackets extending away
from the base of the channel section to the opposite side as the walls of the channel
section; and a plurality of second brackets, each of the second brackets having, a
foot formation which engages in the channel section, the foot formation engaging beneath
the flange formation on each side of the channel section support bar, to slidingly
locate the second bracket in the channel section support bar and an elongate formation
of uniform profile spaced axially of the foot formation for engagement of a seam formed
between two adjacent cladding panels.
[0007] With the cladding system according to the present invention a series of support bars
will normally be mounted in parallel relationship, transverse to the seams between
adjacent cladding sheets to be supported by the bars. Each support bar is sildingly
engaged with formations on a plurality of first brackets which may be pre-secured
to a support structures, in aligned, spaced relationship. A series of second brackets
are then mounted in spaced relationship on the support bar, the second brackets being
located in the channel section support bar with the foot formation parallel to the
longitudinal axis of the bar and then twisted through 90°, so that the foot formation
engages beneath the inwardly directed flange formations on either side of the channel
section. The second brackets may then be slid longitudinally along the channel, to
accurately align the profiles of second brackets located in each of the parallel support
bars, so that seams of corresponding section to the profile of the second bracket,
which are preformed on the cladding panels, may engage the profiles of several of
the aligned second brackets.
[0008] The second brackets in accordance with the present invention may be formed by extrusion,
from suitable material, for example metal such as aluminium or a plastics material,
the extrusion being cut into lengths equal substantially to the width of the channel
section, formations then being formed, which will slidingly engage the flange formations
of the support bar.
[0009] According to a further aspect of the invention, the second brackets are extruded
from aluminium or an aluminium alloy, slots being punched in the side edges of the
bracket, above the foot formation, for engagement of the flange formations of the
support bar. At the same time as forming the slots, the punch die may be adapted to
round the end edges of the profile, in order to provide a rounded lead-in edge, which
will avoid snagging with the cladding panels as they slide over the profiles, as the
roof is constructed and after construction of the roof, to allow for thermal expansion
and contraction.
[0010] While the present invention is particularly suitable for roofing structures and is
described hereinafter by reference to roof structures, it is also suitable for other
cladding systems, for example wall cladding systems.
[0011] The invention is now described with reference to the accompanying drawings, in which:-
Figure 1 illustrates a sectional view of a roof system of the kind to which the present
invention relates;
Figure 2 illustrates a prior art support bracket and roofing bar;
Figure 3 illustrates in perspective view, an assembled section of a roofing system
in accordance with the present invention;
Figure 4 illustrates in perspective view, a bracket of the system illustrated in figure
3, for mounting the roofing system to a support structure;
Figure 5 illustrates in perspective view, the bracket illustrated in figure 4, from
the opposite side;
Figure 6 illustrates in perspective view, a bracket of the system illustrated in figure
3, for mounting a cladding panel to the roofing system;
Figure 7 illustrates in perspective view, a plastic boot for engagement of a foot
formation on the bracket illustrated in figure 6;
Figure 8 illustrates in perspective a modification to the plastic boot illustrated
in figure 7;
Figure 9 illustrates in perspective, a modification to the roofing system illustrated
in figure 1;
Figure 10 is a perspective view of a boot formation used in the modified system illustrated
in figure 9;
Figure 11 is an end view of a channel/bracket assembly of the modified system illustrated
in figure 9;
Figure 12 illustrates a clip for use in a further modification to the roofing system
illustrated in figure 9;
Figure 13 illustrates in perspective a bracket for the modified system using the clip
illustrated in figure 12;
Figure 14 is an end view of a channel/bracket assembly of the modified system illustrated
using the clip illustrated in figure 12;
Figure 15 illustrates in perspective, a modification to the clip illustrated in figure
12; and
Figure 16 is side elevation of the clip illustrated in figure 15.
[0012] Figure 1 shows a roof structure, in which a series of roofing bars 16 are mounted
parallel to one another, at spaced intervals down the slope of a roof. The roofing
bars 16 are supported on rafters or purlins 22, by means of brackets 12, for example
as described above, with reference to figure 2.
[0013] The bars 16 are of channel section, opening towards the rafter or purlin 22, the
brackets 12 extending into the channel, formations 18 on the bracket 12 engaging corresponding
formations on the bar 16. The brackets 12 are provided at spaced locations along the
length of the bars 16, across the span of the roof.
[0014] Further brackets 30 are secured to the upper face of the bars 16, by suitable fastening
means, the brackets 30 being located at spaced intervals along the bars 16. Brackets
30 on each of the bars 16 are aligned with brackets 30 on the other bars 16, up the
roof. The positioning of the brackets 30 across the roof corresponds to raised seam
formations 32 on cladding panels 34. The upper ends of the brackets 30 are provided
with profiles 36 which correspond to the profile of the seams 32 on cladding panels
34, so that the cladding panels 34, with performed seams 32, my be drawn down the
roof, the seams 34 engaging the profiles 36 of aligned brackets 30.
[0015] With the above described system, the roof may be provided with an inner skin (not
shown) made, for example, of corrugated metal sheet, which is secured directly to
the rafters or purlins 22, the brackets 12 being secured to the rafters or purlins
22, on top of this inner skin. Insulation material may then be packed between the
inner skin and cladding panels 34.
[0016] In accordance with the present application, as shown in figures 3 to 7, the brackets
40 which support a roofing bar 60 comprises a body portion 42 of channel section,
with a base 44 and side walls 46. At one end of the body portion 42, an extension
48 of the base 44 is bent at right angles to the opposite side of the base 44 to the
walls 46 and extensions 50 of the walls 46 are bent inwardly, so that the extensions
48 and 50 form a substantially planar surface, holes 52 being provided in extensions
48 and 50, by which the bracket 40 may be secured to the rafter or purlin 22, by suitable
fastening means. Corrugations 54 are provided in extensions 48 and 50 to provide reinforcement
and a more secure location of the bracket 40.
[0017] At the opposite end of bracket 40, an extension 56 of the base 44 is bent at right
angles to the base 44, between the side walls 46. The side walls 46 extend axially
beyond the bent extension 56, extensions 58 of the side walls 46 being bent at right
angles towards one another, so that the extensions 58 extend in a plane parallel to
but spaced axially of the extension 56.
[0018] The roofing bar 60 is of channel section having a base 62 and side walls 64 extending
to one side of the base 62. Flange formations 66 extend inwardly from the free edges
of the side walls 64 , a lip formation 68 extending towards the base 62 along the
inner edges of the flange formations 66. The depth of the bar 60 is equal to the spacing
between extensions 56 and 58 of the bracket 40, so that the bar 60 is a sliding fit
between extensions 56 and 58, extension 56 engaging the base 44 of the channel section
bar 60 and extensions 58 engaging the flange formations 66.
[0019] Further brackets 70 have a planar body portion 72. At the lower end, the thickness
of the body portion 72 is increased to both sides across the width of the body portion,
to form a foot formation 74. A profile 76 extends across the full width of the body
portion, along the upper edge thereof. The width of the body portion 72 is substantially
equal to the distance between the side walls 64 of the channel section bar 60. A pair
of slots 78 are provided one on either side of the body portion 72, adjacent the foot
formation 74, to provide a clearance for the flange/lip formations 66,68, so that
the brackets 70 may be located transversely in the channel section bar 60, the foot
formation 74 engaging between the walls 64 of the channel section and the extremities
of the foot formation 74 engaging between the base 62 and flange/lip formations 66.68.
The brackets 70 are thus capable of sliding along the channel section bar 60. However,
when locating the brackets 70, they may be positioned in the channel at the appropriate
position, the width of the bracket 70 extending along the channel section, and then
twisted, so that the flange/lip formations 66,68 engage in the slots 78, and the extremities
of the foot formation 74 engage beneath the flange/lip formations 66,68. The brackets
70 may then slide along the channel section bar 60, to accurately align the brackets
70 and accommodate any tolerance variations in the width of the cladding panels 34,
[0020] The brackets 70 may conveniently be formed from aluminium or some similar material
by extrusion, the brackets 70 being cut to width, from an extruded strip. The slots
78, may be formed by punching with a die. At the same time as forming the slots 78,
the die may be arranged to form radiuses 80 on the edges of the profile 76, at both
ends. These radiuses 80 allow the seams 32 of the cladding panels 34 to slide over
the profiles 76, when constructing the roof, and also to allow for thermal expansion
after construction, without snagging.
[0021] Figure 7 shows a boot 90, which may be moulded from plastics material. The boot 90
has an axially extending recess 92, which correspond in section to the section of
the foot formation 74. The boot formation 90 slides over the foot formation 74 to
provide a thermal and vapour barrier between the foot formation 74 and the base 62
of the channel section bar 60.
[0022] Figure 8 shows a modified boot arrangement, in which the boot is formed from plastics
material in two halves 94 (only one shown). The axially extending recess 92 of each
half 94 is closed at the outer end 96, so that when the two halves 94 are engaged
on the foot formation 74, the ends will extend beyond the lateral extremities of the
bracket 70 and into frictional engagement with the inner faces of the side walls 64
of the channel section bar 60. In this manner engagement if the ends 96 of boot 94
with the walls 64, will hold the bracket 70 axially of the bar 60. The ends 96 of
the boot formation are radiused in the plane of the base 62 of the channel section
bar 60, in order to facilitate rotation of the bracket 70, so that the slots 78 engage
the flange/lip formations 66/68 of the channel section bar 60. Frictional engagement
between the ends 96 of boot formation 94 is preferably sufficient to hold the bracket
in position, but not sufficient to prevent manual adjustment of the position axially
of the bar 60 or movement of the bracket 70 axially of the bar 60 under forces applied
by thermal expansion of the cladding panel 34. In this embodiment there will be no
need for the base of the boot 94 to engage the base 62 of the channel section bar
60, so that heat loss through this path may be reduced.
[0023] In a further embodiment, as illustrated in figures 9 to 11, bracket 100 has a planar
bottom section 102 which , when the bracket 100 engages the channel section bar 60,
is clear of the base 62 of the channel section, so as to reduce heat loss. In this
embodiment plastic inserts 104 are located in the slots 78, the plastic inserts 104
defining narrow slots 106 which are a close tolerance fit with the flange formations
66 of the channel section bar 60. Engagement of the flange formations 66 in the slots
106 will thus slidable locate the brackets 100 axially of the bar 60, while allowing
the bracket 100 to be engaged with the bar 60 by insertion into the channel with the
width of the bracket 100 parallel to the longitudinal axis of the bar 60 and then
twisting through 90° to engage the flange formations 66 in the slots 106. The inserts
104 will furthermore thermally insulate the bracket 100 from the bar 60.
[0024] Preferably, the inner end 110 of the slots 104 is profiled in the plane of the side
walls 108 of the slots 104, so that the depth of the slot 106 decreases towards the
centre and/or the outer ends 112 of the inserts 104 are radiused in the plane of the
side walls 108 of slots 104, so that when the bracket 100 is twisted at 90°to the
longitudinal axis of the bar 60, the inner ends 110 will frictionally engage the opposed
inner edges of the flange formations 66 and/or the outer ends will frictionally engage
the inner faces of the side walls 64, to hold the bracket 100 axially of the bar 60,
while allowing axial movement when a force is applied thereto in order to permit accurate
axial alignment of the bracket with the seam of the cladding panel 34 or to accommodate
thermal expansion of the cladding panel.
[0025] In a further embodiment, as illustrated in figures 12 to 14 in place of a boot formation,
a pair of clips 120 may be located, one in each of the slots 78 in the bracket 70.
According to a preferred embodiment the clips 120 are pressed from sheet metal, preferable
a metal with poor thermal conductivity, for example stainless steel. For lower load
applications the clips 120 may however be moulded from plastics material.
[0026] Figure 12 illustrates a clip 120 pressed from stainless steel. The clip 120 has rectilinear
a base portion 122. A pair of lugs 124 extend normal to the plane of the base portion
122, to one side of the base portion 122, from one pair of parallel edges of the base
portion 122. A second pair of lug formations 126,127 extend normal to the plane of
the base portion 122, to the side of the base portion 122 opposite to lugs 124. The
lug formations 126,127 extending from edges of the base portion 122 disposed at 90°
to the edges from which lugs 124 extend.
[0027] Flange formations 128 are provided along the side edges of lugs 126,127, the flange
formations 128 on each lug 126 being directed towards the flange formations 128 on
the other lug 126, to leave a gap 130 between adjacent flange formations 128, the
gap 130 being slightly wider than the thickness of the flange formations 66 of the
channel section bar 60. Lug 126 extends beyond lug 127 and the outer end 132 of the
lug 126 remote from the base portion 122 extends beyond the flange formations 128
and is curved in the plane of the lugs 1 26.
[0028] As illustrated in figure 13 the clips 120 locate in the slots 78 in the bracket 100,
the base portion 122 engaging the inner end of slot 78 and the lugs 124 engaging opposite
sides of the bottom section 102. The lugs 124 are pressed into the bottom section
102 of bracket 100, the free ends of the lugs 124 are pressed to a deeper extent than
the ends adjacent the base portion 122, so as to securely locate the clip 120 in the
slot 78.
[0029] As illustrated in figure 14, when the bracket 100 is engaged with the channel section
bar 60, the flange formations 66 engage in the gaps 130 between adjacent flange formations
128 on the lugs 126. The inner edges of flange formations 66 engage the base portions
122 of the clips 120 on either side of the bracket 100 and the ends 132 of the lower
lug 126 engages the inner surface of the walls 64 of the channel section bar 60. The
curved outer end 132 of lug 126 permits the bracket to be twisted into engagement
with the channel section bar 60, in the manner disclosed above, engagement of the
base portion 122 and outer ends 132 of the clips 120, locating the brackets 100 axially
of the channel section bar, while allowing movement of the bracket 100 to permit manual
axial alignment of the bracket with the seam of the cladding panel 34 or to accommodate
thermal expansion of the cladding panel.
[0030] In the modification illustrated in figures 15 and 16, flanges formations 140 on the
lower lug 126 are bent out of the plane of lug 126, away from the flange formations
128 on lug 127. The flange formations 128 on lug 127 are extended towards lug 126,
to provide a gap 130 which is an interference fit with the flange formations 66 of
the channel section bar 60. The flange formations 140 which taper away from the gap
130 will act as a lead in formation, as the bracket 100 is twisted so that the flange
formations 66 of bar 60 engage in the gaps between flange formations 128 and 140.
The flange formations 128 and 140 will thereby resiliently engage each side of the
flange formations 66 of bar 60 to hold the bracket 100 longitudinally of the bar 60,
while allowing movement of the bracket 100 to permit manual axial alignment of the
bracket with the seam of the cladding panel 34 or to accommodate thermal expansion
of the cladding panel. In an alternative embodiment the lug 126 may be of curved configuration,
the curvature being away from lug 127, to provide the lead in.
[0031] Various modifications may be made without departing from the invention. For example
while the above embodiment of the invention relates to a roof structure, the invention
is equally applicable to other cladding systems, for example wall cladding systems,
where the support bars 60 will be secured horizontally, to a suitable support structure
by means of brackets 40. When used to support wall cladding systems, the extensions
50 by which the support bracket 40 are secured to a vertical support member, will
preferable be turned outwardly away from one another, so that they are directed upwardly
and downwardly, thereby improving the strength of the bracket when vertically loaded.
[0032] Furthermore, while in the above embodiment the brackets 70 are formed by extrusion,
from aluminium, other suitable materials may be used. For example the brackets 70
may extruded from a suitable plastics material, which would avoid the need for a separate
plastic boot formation. Alternatively the brackets 70 may be made from any suitable
material, using a process other than extrusion.
[0033] The brackets 40 and channel section support bar 60 are preferably formed from sheet
steel, although again any suitable materials may be used.
1. A cladding system including a support bar (60) made of steel, the support bar (60)
being of channel section, having a base (62) and a pair of side walls (64) extending
to one side of the base (62), inwardly extending flange formations (66) extending
along the edges of the side walls (64) remote from the base (62); and a plurality
of brackets (70), each of the brackets (70) having; a foot formation (74) which engages
in the channel section (60), the foot formation (74) engaging beneath the flange formation
(66) on each side of the channel section support bar (60), to slidingly locate the
bracket (70) in the channel section support bar (60) and an elongate formation (76)
of uniform profile spaced axially of the foot formation (72) for engagement of a seam
(32) formed between two adjacent cladding panels (34), said brackets (70) being formed
from aluminium or aluminium alloy, inserts (90; 94; 104; 120) being provided between
the support bar (60) and brackets (70) to isolate the brackets (70) from the support
bar (60) both thermally and chemically.
2. A cladding system according to claim 1 in which the brackets (70) are formed by extrusion.
3. A cladding system according to claim 2 in which an extrusion defining a foot formation
(70) along one longitudinal edge and a profile (76) along a second longitudinal edge
is cut into lengths corresponding to the width to of the support bar (60), to form
the brackets (70).
4. A cladding system according to claim 3 in which slots (78) are formed in the side
edges of the extruded brackets (70) above the foot formation (74), to provide a clearance
for the flange formations (66) of the channel section support bar (60).
5. A cladding system according to claim 6 on which the slots (78) are punched from the
extruded bracket (70) by means of a punch die.
6. A cladding system according to claim 5 in which at the same time as punching the slots
(78), the punch die is adapted to round the end edges (80) of the profile (76).
7. A cladding system according to claim according to any one of the preceding claims
in which the insert (90; 94; 104) is in the form of a plastic boot formation which
is interposed between the foot formation (74) of the bracket (70) and the channel
section support bar (60).
8. A cladding system according to any one of claims 1 to 6 in which a pair of inserts
(120) are located in slots (78), one slot (78) being provided in each of the side
edges of the extruded brackets (70) above the foot formation (74).
9. A cladding system according to claim 8 in the inserts (120) are formed from stainless
steel.
10. A cladding system according to claim 8 or 9 in which each insert (120) comprises a
clip having a planar base portion (122); a pair of first lugs (124) pressed to one
side of the base portion (122) from spaced parallel edges of the base portion (122),
said first lugs (124) being adapted to engage opposite faces of the bracket (70);
and a pair of second lug formations (126, 127) pressed to the opposite side of the
base portion (122) as the first lugs (124), from edges disposed at 90° to edges from
which the first lugs (124) are pressed, the second lug formations (126, 127) defining
a gap (130) therebetween, the flange formations (66) on each side of the channel section
(60) engaging in said gap (130).
11. A cladding system according to claim 10 in which flange formations (128) are provided
along the side edges of one or both second lug formations (126, 127), the flange formations
(128) on one second lug (126, 127) extending towards the flange formations (128) on
the other second lug formation (127, 126) or towards the other second lug formation
(127, 126) to define the gap (130).
12. A cladding system according to claim 10 or 11 in which the second lug formation (126)
adjacent the foot formation (74) has portions (140) bent out of the plane of the second
lug formation (1 26), away from the other second lug formation (127), to provide a
lead-in formation to guide the flange formations (66) of the channel section support
bar (60) into the gaps (130) between the second lug formations (126, 127).
13. A cladding system according to any one of claims 10 to 12 in which the first lug formations
(124) are indented into the faces of the bracket (70).
14. A cladding system according to any one of claims 10 to 13 in which when the bracket
(70) is installed in the channel section support bar (60), the inner edges of the
flange formations (66) engage the base portions (122) of the inserts (120) on either
side of the bracket (70).
15. A cladding system according to any one of claims 10 to 14 in which a projection (132)
is provided on the second lug formation (126) adjacent the foot formation (74), said
projection (132) abutting the inner surface of the side wall (64) of the channel section
support bar (60), when the bracket (70) is installed in the channel section support
bar (60).
16. A cladding system according to any one of the preceding claims in which support brackets
(40) are provided to mount the support bar (60) to a support structure, said support
brackets (40) having a base formation (48, 50) adapted to be secured to the support
structure and a formation (56, 58), spaced axially of the base formation (48, 50),
for engagement of the channel section (60), so that the support brackets (40) may
be secured to the channel section (60) at longitudinally spaced locations, the support
brackets (40) extending away from the base (62) of the channel section (60) to the
opposite side as the walls (64) of the channel section (60).