Rapid growth in world energy usage has caused concern about supply difficulties, energy depletion, and serious environmental impacts. 'Passive design' is design that takes advantage of the environment factors to maintain a comfortable temperature range. It uses 'natural' sources of heating, cooling and ventilation to create comfortable conditions inside buildings, not like conventional sustainable building using the HVAC or the sustainable technologies, such as insulation material to save energy. Passive design enjoys great potential to reduce the carbon emission without other incremental cost compared with traditional house. This paper investigates the current designing practice and experience to minimise the energy consumption of house operation. A substantial investigation into the impact of passive design measures for a case house is covered. This level of understanding is essential if we are to choose rational passive strategies for future sustainable building.