ABSTRACT
The invention of boilers and chillers made total indoor climate control technologically possible regardless of outdoor conditions, building architecture and use. Buildings became, as Le Corbusier portended during the 1930s, of the same type: hermetically closed and controlled at a constant temperature in all climates (Mahdavi and Kumar, 1996). This energy-intensive solution is supported by the belief that maintaining constant conditions ensures comfort and satisfaction. By applying this approach, however, the building industry failed in many cases to satisfy the comfort needs of occupants. Different studies claim that as many as 43 per cent of occupants are dissatisfied with heating, ventilating and air conditioning (HVAC), and 56 to 89 per cent of government workers regard HVAC as a problem in Europe and the US (Lomonaco and Miller, 1996; DiLouie, 2002). The tendency for the HVAC industry is, then, to keep indoor temperature at a constant value that will dissatisfy the least number of people without affecting productivity since the cost of salaries is 8 to 13 times the cost of building operation.
