Abstract: Due to the presence of high temperature and humidity in the sub-tropical climate like Phuentsholing, residents are forced to use electro mechanical ventilation increasing the energy consumption by a building. Due to this cooling energy demand in buildings represent about 10% of the total energy consumed by the world. Phenomena such as global warming, population growth and longing for luxury living are the key reasons for an increase in energy demand. Particularly, due to the impact of global warming, many people have started to use mechanical system like HVAC for cooling spaces. However, these energy demands can be reduced by 5% to 6% by using natural ventilating mechanism. This paper investigates the impacts of the various type of natural ventilation in building and present the effectiveness of the balconies to induce natural ventilation in building employing Computational Fluid Dynamics.