Windows, why triple glazed?
Better windows mean less heat loss, reduced energy cost and carbon but an important aspect not often addressed is comfort. In the three examples here we have measured single, double and triple glazed windows in the same house this cold winter with outside temp 0 C and inside a warm 21C. None of these have radiators under them so the glass surface temperatures are from room temperature. Existing traditional sash single glazed shows a very cold 9.3 C which causes drafts within the room and condensation to form on this cold surface. The replacement triple glazed window is the German passivhaus Institute certified window. It is wood with carefully insulated frames with a glass surface temperature of 20.3 C resulting in no discomfort or condensation. From the infrared camera colour one can see the glass is yellow and green with only some of the frame blue vs the dark blue back of the single glass. The middle window is a double glass french door with glass surface at 16.9 C and yellow greens. This new french door although wood with seals does not have the care of gaskets and insulated frame of the passivhaus window.