GB2308150A

GB2308150A - Cavity closer with insulating bars of selectable size

Info

Publication number: GB2308150A
Application number: GB9525777A
Authority: GB
Inventors: Nigel Wilson
Original assignee: CARADON EVEREST Ltd
Current assignee: CARADON EVEREST Ltd
Priority date: 1995-12-16
Filing date: 1995-12-16
Publication date: 1997-06-18
Also published as: GB9525777D0

Description

Improvements in or relating to Cavity Closures This invention relates to a cavity closer for use in building, and more particularly for forming and closing a cavity in a double skin wall around a door or window aperture Various types of cavity closing member are already known which are the form of a frame having at least three sides each side of which consists of a profiled bar incorporating two opposed lugs which in use abut the respective inner and outer reveals of the cavity wall and intermediate the lugs and projecting in a transverse direction is a hollow member which in use projects between the Inner and outer skins of the cavity.A heat insulating material may be provided within the cavity of the hollow member To facilitate, for example the fitting of window within a window aperture the cavity closer may be provided with means for securing a window frame which Is designed to seat within the frame of the cavity closer In order to ensure that a window apertures In the Inner and outer leaves of the cavity wall are formed to within acceptable dimensional tolerances, the cavity closer may be used as a former or templet. Where a window, door or the like is to be fitted beneath a lintel, the cavity closer is usually in the form of a three sided frame the side adjacent to the lintel being formed temporarily with a removable strut or similar support.The Inner and outer leaves of the wall are built up to the level of the window cill and the cavity closer Is supported in the desired position of the window aperture The lower side member of the closer Is supported by means the closer lugs resting on the inner and outer leaves of the wall, the hollow member portion then projecting downwardly into the wall cavity. The lugs of the upstanding sides of the closer may then be used as templets by a bricklayer te form the outline of the window aperture.

A problem with known cavity closer designs arises from the fact that wall cavity dimensions are variable and it has hitherto been difficult or relatively expensive to produce cavity closer designs which can accommodate the range of cavity dimensions which are normally encountered. In many conventional systems the portion of the cavity closer which projects between the leaves of the cavity wall does not extend the full width of the desired cavity and therefore cannot provide a templet to maintain a constant dept of cavity around the window reveal.Another known form of cavity closer may be assembled from a limited range of snap-together pvc-U extrusions to obtain an a closer of otherwise conventional form However. an Impracticably wide range of such extrusions would need to be stocked in order to meet all potential building requirements and assembly costs may also be Incurred Providing a wide range of cavity closers covering all likely potential dimensions Is also equally impracticable A cavity closer in accordance with the present invention can mitigate this problem.

A cavity closer in accordance with the Invention also has the advantage that in use the frame elements are adapted for use as a templets to help maintain the depth of the wall cavity around a window or door aperture as well as providing a templet for forming the outline of the aperture.

In one aspect this invention consists in a device suitable for the formation and closure of a cavity wall construction incorporating a window or door aperture or the like wherein the cavity between the inner and outer leaves of the wall opens into the reveal of the aperture, the device comprising a frame corresponding to the dimensions of the required aperture, at least one side element of the frame being provided with retaining means for retaining the side element to the corresponding side of the aperture, the side element further being provided with means for selectively attaching a templet thereto, the selected templet being so dimensioned so as to provide guide means for forming the cavity wall around at least one side the aperture and whereby In use the selected templet closes a cavity of any predetermined distance between the Inner and outer leaves of the cavity wall Advantageously, the device is provided with a limb which in use Is disposed between the Inner and outer leaves of the cavity wall the limb being adapted for the attachment of a selected templet Preferably the limb is adapted for the selective attachment of a first templet to provide guide means for the formation of one leaf of the cavity wall around the aperture and a second templet to provide guide means for the formation of the other leaf of the wall around the said aperture, whereby in use the aperture is formed and the cavity is closed by means of the first and second templets Preferably the limb Is integrally formed with the side element of the closer and is formed with opposed, outwardly directed channel formations each of which Is adapted to retain an edge portion of a templet Alternatively the limb may a separate element and means for securing the limb to the side element may be provided.. At least one channel formation may be provided therein to retain a templet.

More preferably, the limb is provided with detent means for the selective attachment of a templet. thereto. The limb is preferably formed Integrally with the side element, such as by extrusion of a thermally Insulating material such as pvc-U Alternatively other means, for example screw fixings for attaching a selected templet or clamp means may provided for clamping a selected templet directly to the side element. The end portion of the templet remote from the side element may be furnished with a detached limb In the form of fixing plate or bracket which may be screwed or otherwise fixed to the side element. Detent means, such as tangs, may also be provided on the side element to help locate and secure a templet thereto.

In accordance with this invention, a cavity closer device of continuously variable width may readily be fabricated since the templets may be easily cut or otherwise formed to any desired dimensional size. Alternatively or In addition the side element of a closure member in accordance with this invention may be provided with means for the adjusting the relative lateral position of two templet members whereby the position of the templet surfaces for the inner and outer leaves of the cavity wall may be variably adjusted At least one of the side elements forming the closer member may be provided with means for retaining it to the corresponding side of the aperture in the form of a lug extending from the side element which, in use, abuts the reveal of an aperture The side element may for certain applications be provided with two opposed and outwardly directed lugs to retain the element with respect to the reveal the templet being disposed Intermediate the edges of the opposed lugs and arranged to project transversely with respect thereto, whereby In use the limb extends between the inner and the outer parts of a cavity wall.

Preferably, the limb is adapted to retain at least one templet member whereby in use the selected templet member may retained in contact at least one of the cavity wall parts Although a selected templet member may be attached to a limb by any convenient means the limb is preferably is preferably provided with at least one channel formation adapted to retain an edge portion of a templet Preferably, the templets are bars of heat insulating material which may conveniently be In the form of expanded polystyrene foam of rectangular cross section which can be cheaply and easily made In a wide range of cross sectional sizes for Instance by cutting sheet or blocks to any required size.

The use of a thermally insulating templet which fully closes the cavity may be expected to have a higher Insulation value than that obtained by mean of Insulating the hollow core of a conventional cavity templet which does not substantially bridge the wall cavity towards either side In order that the invention may be more clearly understood four embodiments will now be described by way of example only with reference to the accompanying drawings in which Figure 1 is a cross sectional drawing of a side element a first embodiment of a cavity closer installed within a window aperture formed in a cavity wall Figure 2 is a cross sectional drawing of a side element of a second embodiment installed as shown in Figure 1 and Figure 3 is a cross sectional drawing of a side element illustrating a third embodiment of the invention positioned in situ.

Figure 4 is a cross sectional drawing of a side element Illustrating a fourth embodiment of the Invention Referring to Figure 1 one of the elongate side elements 2 of a three-element cavity closer is in the form of single pvc-U extruded profile having opposed lugs 4, 6 and an limb in the form of a profiled hollow section limb which In use, as shown extends from the plane of the lugs into the cavity between the Inner and outer cavity wall parts 10. 12 respectively The lower part of hollow section integral limb 8 Is provided with opposed legs 14 16 directed towards the outer and Inner wall parts 12, 10 respectively. The outer end portions of the legs 14. 16 are each provided with a tooth formation 18.Similar tooth formations 18 are also provide on the lower surfaces of the lugs 4 and 6 Polystyrene foam insulating bars 20 of rectangular cross section are selected to ensure that any predetermined cavity width d as may be required are be closed when a bar 20 Is attached to each of the opposed sides of the hollow section limb, as shown. Attachment of the bars 20 to the opposed sides of hollow section limb 8 Is achieved by pressing the bars 20 into contact with the sides of limb 8 in which position they are retained by teeth 18 engaging the opposite sides of each Insulating bar Clips 26 are also provided to further retain the bars 20 in position.

The cavity closer is installed in a conventional way. The inner and outer leaves of brick or block cavity wall 10,12 are built up to window cill height as shown in Figure 1 and an assembled cavity closer with the insulation bars attached is supported vertically with the lugs 4, 6 of the lower horizontal element abutting the reveals 22, 24 of the window aperture and the extending limb 8 extending between Inner and outer leaves 10, 12 of the cavity wall. The upstanding elements of the cavity closer, not illustrated provide a templet for the brickwork surrounding the window aperture.

However, as may be seen from Figure 1, the templet for the Inner and outer leaves is provided by the lugs 6 and 4 and the exposed outer sides of the insulating bars 20.

Referring to Figure 2 a cavity closer similar to that described with reference to Figure 1 is shown in part, fitted in situ, into a window aperture In which the outer leaf has a raised abutment ledge 28 for locating and supporting the outer frame of a window. In this case a resilient sealing strip 30 is provide to accommodate small dimensional variations in the structure Although In the case of this embodiment the closer member Is provided with two opposed lugs 4. 6 only the lug 6 abuts a reveal 24 to locate the closer In position. The other lug 4 serves to help retain the insulation bar 20 in position and other means may be provided to serve this purpose.

Referring to Figure 3 a cavity closer similar to that described with reference to Figures 1 and 2 is shown. In part fitted In situ Into a window aperture provided with a tile external window cill In this case the cement bed 30 fills the outer channel of the side element 2 formed by the lug 4 the leg 14 and the outwardly facing wall of the limb 8. Accordingly the cavity may be closed In this case by the use of a single insulating bar 20 attached to the interior side of the limb 8. As the case with the embodiment illustrated in Figure 2 the lug 4 does not serve the support function of the same part when used in the arrangement shown In Figure 1 and may be dispensed with . Alternative means for retaining the cement bed may be provided.

Referring to Figure 4, the side element has a first member 28 which has opposed, extending lugs 4 and 6 which retain the closer against the reveal parts 12. 10 as previously described. Member 28 is provided with a central channel section 29, the outer walls of which provide abutment surfaces for the edges of Insulating bars 20.

The side element is provided with a separate limb 30, In the form of a channel shaped profile having opposed flanges 32, 34 provided with inwardly directed tangs 18. The bars 20 are cut to any thickness as may be required so as to provide, In use, a guide for forming and so as to close the cavity of a window or like aperture thus formed. a cavity of any pre determined dimension between the leaves 10 and 12 of the cavity wall. Fixing means not shown are provided along the line a-a to connect the element 28 and limb 30 so as to clamp the bars 20 In the required position.

Claims

1 A device suitable for the formation and closure of a cavity wall construction incorporating a window or door aperture or the like wherein the cavity between the inner and outer leaves of the wall opens Into the reveal of the aperture the device comprising a frame corresponding to the dimensions of the required aperture, at least one side element of the frame being provided with retaining means for retaining the side element to the corresponding side of the aperture the side element further being provided with means for selectively attaching a templet thereto, the selected templet being so dimensioned so as to provide guide means for forming the cavity wall around at least one side the aperture and whereby In use the selected templet closes a cavity of any pre-determined distance between the inner and outer leaves of the cavity wall.

2. A device as claimed in claim 1 In which the side element Is provided with a limb which In use Is disposed between the Inner and outer leaves of the cavity wall the limb being adapted to retain a selected templet

3. A device as claimed In Claim 2 in which the limb Is adapted for the selective attachment of a first templet to provide guide means for forming one leaf of the cavity wall around the aperture and a second templet to provide guide means for forming the other leaf of the wall around the said aperture whereby in use the cavity Is closed by the first and second templets

4. A device as claimed in Claim 3 In which the limb Is provided with a channel formation adapted to retain an edge portion of a templet

5 A device as claimed in Claim 2. 3 or 4 In which the limb Is provided with detent means for the selective attachment of a templet thereto

6.A device as claimed in any preceding claim in which clamp means are provided for clamping a selected templet to the side element

7. A device as claimed in any preceding Claim in which the means for retaining the side element to the corresponding side of the aperture Is In the form of a lug extending from the side element which, In use, abuts the reveal of the aperture formed in a cavity wall,

8. A device as claimed In any preceding Claim in which the templet Is selected from a range of pre-sized bars of an Insulating material.

9. A device as claimed in any preceding Claim in which the side element is integrally with the limb member.

10. A frame component suitable for the fabrication of a device as claimed in any preceding Claim comprising a frame element having means for retaining the element to the reveal of an aperture In a cavity wall and means for selectively attaching a templet thereto, the templet being so dimensioned and arranged to provide a guide for the construction of a leaf of a cavity wall around the edge of an aperture to be formed therein, and which in use projects between the Inner and outer leaves of the cavity wall and which in use serves to ciose the cavity.

11 A cavity closure device or frame element substantially as described with reference to Figures 1, 2, 3 or 4 of the accompanying drawings.