Characterising the use of windows in thermal simulation

The use of windows is a key adaptive opportunity in naturally ventilated buildings especially in summer when the building is likely to be free-running. In these circumstances the use of windows can be on important key to occupants remainingcomfortable, particularly in warm weather. This aspect of buildings is poorly covered in existing thermal simulations in which occupant behaviour is ignored or presented in a very basic fashion. This paper presents an approach to the simulationof window opening behaviour which has been developed from observations of occupant behaviour in UK offices. The paper presents examples of the use of the adaptive window-opening algorithm which demonstrate the advantages of opening windows to comfort and the cost in terms of extra energy use. The paper suggests way in which the methodologycan be extended to other controls and other climates.