Center for the Built Environment

Although naturally ventilated buildings are gaining popularity, it is commonly seen that buildings are not always fully naturally ventilated, but sometimes combine both natural ventilation and mechanical cooling; these are referred to as ‘mixed mode’ (MM) buildings. The temporal and spatial method of cooling the space further classifies the mixed mode building as changeover, zoned and concurrent type (Center for the Built Environment website). Typically in office buildings in India, part of the building is AC while the rest of it is NV possibly due to programmatic requirements such as conference rooms and computer labs or due to warm indoor conditions. In such zoned mixed mode (MM) buildings, occupants move frequently between the AC and NV zone which poses an interesting question - Does the experience of comfort in the AC zone influence the comfort expectation of occupants who primarily work in the NV zone? To answer this question, the physical environmental conditions, use of adaptive actions and thermal comfort responses need to be evaluated in both the zones of the MM building.