Abstract

Current multi-pane windows have a very low heat loss but their solar transmittance is low resulting in a loss of daylight and solar gains. Multi-pane windows also require framing arrangements that are difficult to retrofit to existing apertures in many existing buildings. A contiguously sealed evacuated double-glazing with low long-wave radiative emittance coatings on its internal surfaces, no heavier than conventional double-glazing, with good visual transmittance suitable for retrofitting to existing buildings, has been analyzed experimentally. Measured heat transfer coefficients and visual transmittances of laboratory fabricated evacuated glazing samples, along with theoretical predictions of center of glazing thermal conductance are presented.