Abstract: A fire-retarding window assembly, includes a frame; and at least two transparent window panels which are held to the frame at two opposed edges and which are disposed in edge-to-edge relationship with one another, wherein each transparent fire-retarding window panel includes a plurality of sheets of glazing material and at least one intumescent layer sandwiched between sheets of the glazing material, at least one sheet of glazing material of each panel having a fire resistance which is at least equivalent to that of a sheet of annealed soda-lime glass having the same longest dimension as the panel, having a ratio of its longest dimension to its thickness of not more than 340:1, and having a minimum thickness of 5 mm, and wherein adjacent edges of successive transparent fire-retarding window panels are sealed with a non-structural filler material which is one of non-flammable or self-extinguishing.

Abstract: A glazing panel which is transparent and fire-resistant, including at least one vitreous structural ply including at least one rough-faced ply composed of vitreous material having a mean coefficient of linear thermal expansion over a temperature range of 20.degree. C. to 300.degree. C. which is not greater than 7.5.times.10.sup.-6 K.sup.-1 and having a rough face for which roughness, R.sub.tm, is not less than 0.1 .mu.m; and at least one layer of intumescent material directly bonded to and in contact with the rough face of the at least one rough-faced ply.

Abstract: A light-transmitting fire resistant glazing panel includes at least two vitreous sheets between which is sandwiched at least one intervening layer of intumescent material, for example, of hydrated sodium silicate. Two of the vitreous sheets are of different thicknesses and they are bonded together via the sandwiched intumescent material. The thinner of the two vitreous sheets is of conforming size to the thicker sheet and the thinner sheet and intumescent layer are shaped to leave the main face of the thicker sheet to which they are bonded exposed at a plurality of local marginal areas. This allows a hinge bracket 11 to be attached to the thicker sheet 1 at the exposed area 5 by a plurality of bolts leading through holes in the thicker sheet. The bolts may comprise sheathes, e.g. of nylon, or they may lead through bushes, e.g. of nylon, to avoid direct contact between the metal of the bolts and the glass if this is desired.

Abstract: A fire-screening glazing panel including a plurality of sheets of vitreous material and at least two spaced layers of intumescent material each sandwiched between sheets of the vitreous material. At least two of the plurality of vitreous sheets are internal vitreous sheets sandwiched between the at least two intumescent layers, and the at least two internal vitreous sheets are laminated together without intervening intumescent material.