Materiales de Construccion (Dec 1994)
Los vidrios de baja emisividad
Abstract
The use of low-emittance coating (low-E) glasses in Europe and the United States is not recent (they make use of them long since: 10-15years), nevertheless they are almost unknown in Spain, in all respects, in spite of being commercialized long since by different houses, specialists in these matters. We run into a lack of regulation about the qualities and stipulations these elements must comply with, since the regulations governing the thermal insulation of the buildings (CT-79) refers to the generic and peculiar qualities of the glazed openings, but these regulations do not approach the question of the real behaviour of the glazed openings with low-emittance glasses and other semi-transparent elements. The expenditure of energy and the lighting characteristics of the openings are not yet unforeseen, so far. These properties undergo a variation with regard to the base-glass or the support, due to the low-emittance coating. The article is organized in to three parts. The first part is the analysis of the functional characteristics and the lighting properties of the glasses from a general point of view. The second one explains what low-emittance glasses are, and the way of obtaining them (very briefly); according to the kind of process of obtaining the low-emission coating, the proceedings of low-emission glasses are gradually limited. Finally, the third part deals with the thermic characteristics of whole glazing, and specially with the glazed openings, from the point of view of a functional consistency for both glass and joinery.