This study was initiated to determine the extent of cold temperature air leakage from operable windows available in todays marketplace and the impact that this has on the energy consumption of a house. During the heating season, changes in the window's leakage characteristics, as a result of thermal and pressure effects, were to be included. At two laboratories, air-leakage tests down to-30°C were performed on 35 windows, enough to reach some general conclusions about performance.
The paper examines the extent to which user's intervention may compromise the therrmal performance of small sunspaces in the context of a Solar Energy Demonstration Project at Easthall in Glasgow (55°52'N), which was monitored from September 1992 to May 1994. Results indicate a tendency to close down windows etc. late in autumn and open them up early in spring relative to heat demand. In other words a user – driven energy load due to ventilation is higher in autumn and spring than in the central winter period.