GB2111109A

GB2111109A - Insulated window or door frames

Info

Publication number: GB2111109A
Application number: GB08229760A
Authority: GB
Inventors: Colin Martin White
Original assignee: BKL Extrusions Ltd
Current assignee: BKL Extrusions Ltd
Priority date: 1981-10-20
Filing date: 1982-10-18
Publication date: 1983-06-29
Also published as: GB2111109B

Abstract

A frame member for a window or door, with a metal element and a thermally insulating covering 16,17,19, e.g. of a plastics material which may be foamed, on both sides of the metal element so that the metal element is insulated and inaccessible when the window or door is installed. A removable glazing bead 20 also has a thermally insulating covering 21. <IMAGE>

Description

SPECIFICATION Window or door frame member This invention relates to a frame member for use in a window or door assembly.

Frame members for use in window or door assemblies commonly are made of metal, typically an aluminium alloy which has been extruded in the desired cross-sectional shape.

It is known that such frame members can have a covering of a thermally insulating material on a surface thereof which is accessible when the window or door is installed in a building structure, with the object of cutting down energy loss through the frame and avoiding condensation thereon within the building. It will be appreciated that in the absence of such an insulating covering the thermal conductivity of the frame is very great compared with glass in the window or door, particularly if double glazed. It is an object of the present invention to provide a further improved frame member.

Accordingly, the invention provides a frame member for a window or door assembly, comprising a metal element having on each of two portions thereof, which portions would externally accessible from opposite sides of the window or door assembly when installed, a covering of a thermally insulating material, and a removable glazing bead element also having a covering of a thermally insulating material and engaging one of said portions of said metal element.

One advantage of the invention is that the thermal conductivity of the frame as a whole can be reduced still further by provision of insulating material on both sides thereof, including the glazing bead element. A further advantage is that suitable colour finishes can be selected for the insulating material on both sides of the metal frame member.

These and other features of the invention will now be described by way of example with reference to the accompanying drawings, of which: Figure 1 is a section through a frame member in accordance with the invention; Figure 2 is a section through a modification of the frame member of Fig. 1.

Referring firstly to Fig. 1 of the drawings, the frame member there illustrated is intended to form a mullion or transom of a window. It comprises an elongate extrusion of an aluminium alloy, with a box section portion 10, and a substantially T-shaped formation 11 protruding from one side thereof and two formations 12, 13 extending laterally from the other side of the box section. The formations 12, 13 are mirror image identical, and between them extend two barbed formations 14, 15.

The formations 12,13 each have a thermally insulating covering 16, 17, respectively, each of which is hooked over the end of the formation 12, 13 and pressed onto the respective barb 14, 15. The coverings 16, 17 are of a plastics material, either an extruded shell of an appropriate material into which a foam filling has been extruded or a selfskinned foamed plastics material such as that known by the registered trade mark Celuka.

The gap between the coverings 16, 17 is filled by a pushed in resilient strip 18.

The T-shaped formation 11 carries a thermally insulating cover 19 of a plastics material, secured thereto by being snapped over the free ends of the limbs of the T-shaped formation 11. A glazing bead 20, again an aluminium extrusion and also provided with a thermally insulating covering 21 snap fitted thereon, is provided, and includes a formation in the form of a lip 22 which engages behind the end 23 of the thermally insulating covering 19 which has been snapped over the free end of the T-shaped formation 11. Typically the cover 19 will be on the exterior of a building in which the frame member is installed.

When the illustrated frame member is installed as part of a window, glass, in the form of sealed double glazing unit 24, is received between the formation 12 and glazing bead 20, and retained by wedge gaskets 25.

Another glazing unit is received by the formation 13 and its corresponding glazing bead (not shown). In such an installation, no metal part of the assembly is accessible, either on the interior of the building or the exterior thereof. This gives good thermal insulation, and, as already referred to, the colour of the insulating coverings can be selected as desired.

Referring now to Fig. 2, this shows the manner in which the metal element of the frame member may be used with a thermally insulating covering on one side only thereof.

In this case, a glazing bead 26 without an insulating covering engages by a lip 27 behind a projection 28 protruding from the inner surface of the limb of the T-shaped formation at a position spaced from the free end thereof.

Thus the single design of metal element may be used in a frame member both with a thermally insulating covering on both sides thereof and with the covering on one side only.

One advantage of this construction, apart from the improved insulation, is that it enables replacement of the exterior covering of the frame member, if the original covering becomes discoloured due to weathering, accidentally damaged, or merely if a change of colour is required. Alternatively the exterior covering could be removed completely, with a penalty in insulating effect if the metal frame member remains exposed.

The exterior covering material could be a material with a foamed core, as for the interior insulating covering.

Claims

1. A frame member for a window or door assembly, comprising a metal element having on each of two portions thereof, which would be externally accessible from opposite sides of the window or door assembly when installed, a covering of a thermally insulating material, and a removable glazing bead element also having a covering of a thermally insulating material and engaging one of said portions of said metal element.

2. A frame member according to Claim 1 wherein said metal element is adapted to engage a glazing bead element not having a covering of a thermally insulating material.

3. A frame member according to Claim 1 or Claim 2 wherein said covering of thermally insulating material is of a plastics material, having snap engagement with said one portion of said metal element and/or said glazing bead element.

4. A frame member according to any one of the preceding Claims wherein said covering on said portion of said metal element which does not engage said glazing bead element is of a plastics material having a solid shell or skin and a foamed interior.

5. A frame member substantially as hereinbefore described with reference to the accompanying drawings.