The energy efficient building asset is the key to the building’s sustainability. To approach the concept of energy efficient building assets in a sub-tropical climate, building assets must adopt a number of innovative strategies to take advantage of subtropical climate. A framework for understanding the climate comfort building relationship was proposed (Olgyay, 1953). This understanding was adapted to the psychrometric chart and was further developed to produce 'building bioclimatic chart' (Givoni, 1969). Milne (1979) elaborated these further and developed boundaries for outdoor conditions in terms of temperature and humidity which could be made comfortable by various energy conservation and management techniques. The importance of energy efficiency improvement in building asset is elaborated. Appropriate energy efficient technologies for building systems particularly Heating, Ventilation and Air Conditioning systems (HVAC) for subtropical/ warm humid climates is presented. The effectiveness of climate-responsive building design and space-conditioning strategies within the building assets in sub-tropical Queensland, Australia is reviewed and discussed.