This invention relates to edge seals for windows and panels and, more especially, to fire-resistant edge seals for use with conventional glazing beads.

Glazing beads are known which comprise a channel section extruded from plastics material and having a combustible core of intumescent material which expands when subjected to excessive heat. Such glazing beads are expensive to produce and provide only limited protection when subjected to fire. Examples of publications which describe such glazing beads include patent applications GB 2287739, GB 2212546 and DE 3436236. The beads disclosed in these publications all relate to beads for use with a specifically dimensioned window or panel.

The present invention sets out to provide an edge seal for use with a glazing bead for a window or panel which can accommodate a range of glass sheet or panel thicknesses and provides enhanced protection against fire.

According to the present invention in one aspect, there is provided an edge seal for a window or panel which comprises a channel section strip of a relatively rigid plastics material comprising an elongate base and walls upstanding from each side edge of the base, a lip extending inwardly towards the centre line of the channel section strip from the end of each wall remote from the base, and a relatively flexible protrusion extending inwardly towards the longitudinal centre line of the channel section strip from the edge of each lip, and a strip of intumescent material in contact with the inner surface of each side wall between the base and the under surface of each lip.

Each flexible seal is preferably tapered towards its distal edge and is inclined upwardly towards the centre line of the channel section strip.

The invention will now be described, by way of example only, with reference to the accompany diagrammatic drawing in which the sole Figure is a section taken through an edge seal in accordance with the invention.

The illustrated edge seal is relatively rigid and is produced continuously as an extrusion from a synthetic thermoplastic material. As will be seen from the drawing, the edge seal is of channel section having a base 1 and upstanding side walls 2, and includes inwardly extending lips 3 formed with upwardly inclined and inwardly extending projections 4. The projections 4 are relatively flexible and project inwardly to define a separation gap which is slightly less than the thickness of the glass sheet or panel to be located within the channel of the edge seal.

Positioned along the inner face of each side wall 2 is a strip of intumescent material 5, each intumescent strip 5 being retained in place by its contact with the base and the under surfaces of the respective lip 3.

In use, lengths of edge seal are positioned around the side edges of a sheet of glass or panel material with the ends of the edge seal suitably shaped to accommodate corners and the like. The sheet or panel with the mounted edge seals are then positioned within a frame in the conventional way and masked by conventional glazing beads. These beads may be rebated to receive each exposed side of the edge seal. The flexibility of the projections 4 ensure an effective seal with the mounted glass sheet or panel.

In the event of fire, the intumescent strips rapidly expand and move over the adjoining sides of the glass sheet or panel to assist

retention of the sheet or panel in place and to inhibit the passage of fire and smoke.

It will be appreciated that the foregoing is merely exemplary of glazing gaskets in accordance with the invention and that modifications can readily be made thereto without departing from the true scope of the invention as set out in the appended claims.