The global community is searching for realistic options to reduce the use of fossil fu- els. The vastly growing build- ing sector will be one of the major concerns in the next 25 years. Between 2010-2030, 84 billion m² of new and rebuilt buildings will be constructed in cities worldwide. That is the equivalent to the rebuilding of the entire US building stock three and a half times over. Nearly 60% of global develop- ment will occur in Asia, about 9% in Latin America, and most of these new buildings will be constructed in tropical, warm and humid climates (McKinsey Global Institute, 2015). In maintaining the type of indoor conditions, we have learned to universally expect, buildings require massive energy inputs. The way we define comfort plays a signif- icant role in this. What if we challenge this definition? Are the conventional targets to cool and condition spaces the only way to achieve thermal comfort? ...
Common practice in many tropical countries is to design air conditioned buildings that operate at 22 °C to 24 °C all year, satisfying the stringent specifications outlined in the established Thermal Comfort Standards of ASHRAE 551, ISO 77302, EN 152513 or other locally derived standards. These thermal comfort standards are underpinned by a heat balance model developed in the 1970s for air conditioned spaces. The derived ‘static’ comfort standards tend to prefer lower temperatures and low air speeds as achieved with conventional air-conditioning techniques. As a consequence of low temperature and energy saving these buildings are designed as sealed-off from the environment and do not take advantage of favorable outdoor conditions available. Façades are closed and natural venti- lation is understood to be in conflict with air conditioning.