A glazing unit comprises a substrate ply and a laminating ply laminated to a surface of the substrate ply. A coating on the laminated surface of the substrate ply is a film stack comprising an electrically conductive film of silver metal covered by a tantalum pentoxide dielectric film immediately adjacent the laminating ply. Between the silver film and the tantalum pentoxide film is an adhesion film of metal selected from zinc and copper. Applications include, for example, glazing units for solar load reduction and electrically heated glazing units.