Fire-resistant panel

A transparent, fire-resistant, glazing panel 8 comprises at least one layer 10 of intumescent material bonded to at least one structural ply 9, 11 of the panel. The panel incorporates at least one ply 9 of vitreous material having a mean coefficient of linear thermal expansion over a temperature range of 20 DEG C to 300 DEG C which is not greater than 7.5x10 K . That ply 9 has a rough face 13 (rugosity Rtm not less than 0.1 mu m) to which a layer 10 of intumescent material is directly bonded. The rough-faced ply may be of vitro-crystalline material, and an exposed face 12 may be smooth. The vitro-crystalline material may be based on the ternary system Li2O - Al2O3 - SiO2, and the intumescent material may comprise hydrated sodium silicate. A method of manufacturing such panel comprises forming a sandwich assembly from a plurality of vitreous plies 9, 11 with successive vitreous plies in contact with an intervening layer 10 of intumescent material and subjecting that sandwich to heat and pressure conditions such as to degas the inter-ply spaces of the sandwich and to cause the sandwich assembly to be bonded together as a transparent laminate 8. At least one vitreous ply 9 is a ply of vitreous material having a mean coefficient of linear thermal expansion over a temperature range of 20 DEG C to 300 DEG C which is not greater than 7.5x10 K , such ply having a rough face 13 (Rtm not less than 0.1 mu m) in contact with a layer of intumescent material.