|When it comes to providing an unobtrusive secondary glazing system, the hinged unit provides the most appropriate solution, since there are no transoms or mullions to spoil the view. The reduction in noise, and improvement in thermal insulation, greatly enhances both the living and working environments.
||The hinged unit can be manufactured in two main types. The single hinged unit opens on a restricting friction stay. Where the application is on a larger scale, the friction stay is replaced with a butt hinge. they have developed and rigorously tested a variety of butt hinges for differing leaf weights. The double hinged unit has been primarily designed to fit in front of larger Windows or French Doors, utilising the same range of hinges.