As a typical thermochromic material, the vanadium dioxide (VO2) has a great potential for building energy efficiency development. In this study, the VO2 glazing's application performance was first demonstrated in full-size, and simulated with a software of high credibility. For a 2.9 m x 1.8 m x 1.8 m low-mass room whose window's size is 1.65 m x 1.65 m, the measured results showed that the room with the VO2 glazing saved 10.2-19.9% cumulative cooling load than that with an ordinary glazing during the demonstration. The application performance to a conventional residential room in the hot summer and warm winter zone was simulated in BuildingEnergy, a simulation software developed by the authors. The simulated results showed that the use of the VO2 glazing could save 9.4% electricity consumption. The effects of the window's orientation and the area ratio of window to wall were also discussed in this study. (C) 2013 Elsevier B.V. All rights reserved.