A way of designing and constructing buildings and manipulating the environment within buildings, taking into account climate and environmental conditions to help achieve thermal comfort, reduce the consumption of fossil fuel and cut electricity bills. Designs include optimum site selection (such as exposure to winter sun or summer breeze), use of building components for roof, walls, floors (can be used as heat storage) and windows (for increasing daylight), etc. Green building programs aim to improve energy efficiency and the integration of renewable energy sources in buildings. It is also the practice of increasing the efficiency with which buildings use a variety of resources whether energy, water, materials while reducing the building’s impact on human health and the environment.