[0001] This invention relates to a curtain wall system for the cladding of buildings using
gaskets and in particular relates to the provision of additional retention for such
systems when required because of extreme windloads or local regulations.
[0002] In our US patent No. 4631884 there is described a novel wall system which comprises
an auxiliary framework attached to the main steel work of a building and made of a
plurality of framework members. Each such framework member has as generally T shaped
cross section and includes an elongated central support portion defining a pair of
opposed shoulders for seating the edges of a pair of adjacent infill panels. The framework
member has a channel generally parallel with the support portion and shaped to receive
and grip the foot of a flexible gasket, the gasket having a transverse limb adapted
to extend toward or over the associated shoulder to bear against and retain the infill.
The thickness of any given infill may be substantially the same as the cross sectional
length of the support portion of the associated framework member. The term 'curtain
wall' as used herein is intended to cover systems of this type as well as conventional
curtain wall systems.
[0003] One advantage of the system above described is the flexibility accorded the system
to enable subsequent alerations and/or extensions to be accommodated. Thus the removal
of one gasket allows its associated infill to be removed and replaced with, for example,
an infill bearing an opening window, without disturbing adjacent infills or retention
devices. (The term infill includes a construction panel, glazing unit, or the like
which is capable of being used as cladding for a building, that is to constitute the
internal and external walling for a building).
[0004] While the gasket provides adequate retention of the infill for all normal uses, in
certain instances, for example in places of exceptionally high wind loading, or where
local regulations require it, it may be necessary to provide in addition to the gasket
an independent means of retaining the infill within the framework. Such a means is
disclosed in our UK patent No. 2093497. There, rods or plates are inserted through
corresponding holes in the side walls of the framework portion so as to overlie edge
portions of the adjacent infill. However this latter method has not proved completely
satisfactory in practice, especially since the plate or rod will generally overlie
infills on either side of the given framework section and thus to some extent reduce
the flexibility of the system.
[0005] The invention seeks to provide a form of retention for use with gasket-type curtain
wall systems improved in the above respects.
[0006] According to the present invention there is provided a curtain wall system for the
cladding of a building which comprises framework members for receiving and seating
infill panels, and gaskets adapted to be received within the framework members to
extend over and retain the infills, characterised in that, for a given infill, one
or more clips are provided which locate in respective channels in orthogonally disposed
adjacent framework members and retain the corner of the infill.
[0007] The clips may be made of a suitable material such as sheet metal, for example sheet
steel, and are conveniently generally 'U'-shaped in appearance. The U-shaped 'legs'
of the clip are preferably skewed at an angle of approximately 45 degrees outwardly
so as to be at an angle of approximately 90 degrees to one another. This allows the
legs of the clip to fit against the sides of a vertical and transverse framework member
adjacent a corner. The bottom of the legs of the clip preferably are folded over to
provide a detente which is a lock-fit in a channel provided in the framework members.
The channel may be provided specially for the clips but, in a preferred form of the
invention, the channel is one already provided in the framework member, for example
to retain an adaptor used in the system of the above mentioned US patent for adapting
the system to different thicknesses of infill member.
[0008] Preferably four such clips are used with each infill member, one adjacent each corner.
However, if desired a lesser number may be employed, e.g. a pair of diametrically
opposed corners where this will give adequate retention. The clip system is easily
fitted after the infill has been placed in position and before the gasket is inserted
completing the operation.
[0009] The invention will be described further, by way of example, with reference to the
accompanying drawings, in which:
Figure 1 is a partial perspective view of a curtain system embodying the retention
of the invention;
Figure 2 is a vertical section through another form of framework member; and
Figure 3 is an elevational view of the embodiment of figure 2.
[0010] Referring to the drawings, a curtain wall system generally designated 10 is illustrated
comprising vertical framework members 12 horizontal framework members 14. The vertical
framework members 12 include a reinforcing box section 16 and thus are conventional
curtain wall members. The horizontal members 14 include no such box portion but are
otherwise identical to the members 12.
[0011] Each of the framework members has a generally T-shaped cross section and includes
an elongated central support portion 20 defining a pair of opposed shoulders for seating
the edges of a pair of adjacent infill panels 22, 24. As illustrated, the infill panel
22 is a double glazed unit, while the infill panel 24 is a cladding panel. The framework
members 12, 14 have channels 26 shaped to receive and grip the foot 28 of a flexible
gasket 30. The gasket 30 has a transverse limb 32 adapted to extend toward or over
the associated shoulder to bear against and retain the infill 22, 24. The thickness
of the infill 24 is substantially the same as the cross sectional length of the support
section 20 of the associated framework. However the infill 22 is of substantially
lesser thickness and the difference is taken up by an adaptor clip 34 retained in
one of two channels 36, 38 in the support portion 20 as fully described in our above
mentioned US patent. As illustrated the other channel 38 adjacent the infill 22 retains
a beading member 40 which aids sealing and/or drainage of the infill unit 22.
[0012] In normal use of the system illustrated, one of the infill members, for example the
glazing unit 22, would be placed into the square opening defined by the framework
members 14 and 12 and the gasket 30 fixed into place therearound thus retaining the
infill 22. Where additional retention is required, in accordance with the present
invention, additionally two or more clips 42 are provided. These are generally U-shaped
in appearance having a central retaining portion 44 and two legs 46. The legs 46 are
skewed with respect to the central portion 44 so as to be substantially mutually orthogonal.
As can be seen more clearly in figure 2, each of the legs 46 terminate in a curled
over portion 48 which acts as a detente with the sloping sidewall of the channels
38. Thus, once the infill 22 has been placed in the opening formed by the framework
members 12, 14 four such clips 42 as shown in figure 1 with the retaining portion
44 across each corner of the infill with the legs 46 conforming closely to the adjacent
side walls of the framework members 12, 14. Pushing the clips downwardly (towards
the infill) allows the turned up portions 48 to 'lock' into the channels 38 where
the clips are thus retained and, in turn, retain the infill. The gaskets 30 are then
put in place in the normal way.
[0013] Removal of the clips and/or the infill is a simple reversal of the above process.
The gasket 30 is removed exposing the clips and a tool slid between the framework
member sidewall and the clip leg 46 to dislodge the turned up portion 48 from its
channel 38. Each clip may then be removed after which the infill is simply taken out.
This procedure does not disturb adjacent gaskets or infills and thus the flexibility
of the system is preserved in that if a cladding panel is to be replaced with, for
example, a window, this may be done quickly and simply without disturbing the entire
wall of the building.
[0014] The device of the invention provides a simple easy to use and extremely economical
solution to the requirement to provide additional retention to building systems of
the type described when this is necessary for conditions of wind loading or local
regulations.
1. A curtain wall system for the cladding of a building which comprises framework
members for receiving and seating infill panels, and gaskets adapted to be received
within the framework members to extend over and retain the infills, characterised
in that, for a given infill, one or more clips are provided which locate in respective
channels in orthogonally disposed adjacent framework members and retain the corner
of the infill.
2. A system as claimed in claim 1 in which the clips are made of sheet metal and are
generally 'U'-shaped in appearance.
3. A system as cliamed in either of claims 1 or 2 in which the U-shaped legs of the
clip are skewed at an angle of approximately 45 degrees outwardly so as to be at an
angle of approximately 90 degrees to one another.
4. A system as claimed in any of claims 1 to 3 in which the bottom of the legs of
the clip are folded over to provide a detente which is a lock-fit in a channel provided
in the framework members.
5. A system as claimed in claim 4 in which the channel is one already provided in
the framework member, for example to retain an adaptor.
6. A system as claimed in any of claims 1 to 5 in which four such clips are used with
each infill member, one adjacent each corner.
7. A system as claimed in any of claims 1 to 5 in which a pair of clips are used in
diametrically opposed corners.
8. A system as claimed in any of claims 1 to 7 wherin the clips are fitted after the
infill has been placed in position and before the gasket is inserted completing the
operation.