The diagram below shows how heat is lost and energy wasted in a house because of air getting into and out of the house.
The air circulation, such as air leaking into and out of the house, is presented in the diagram. Interestingly, although the house has three level, all of the air leaking out of the building is passing through the highest level of the building.
First of all, on the lowest level, basement, crawl space and dryer vent are used by the air to get into the building. Furthermore, in the ground level, a great number of air come into the house by using several spot. Kitchen fan vent and window are used by air to come inside the kitchen. Besides that, air get into it by using window and main door in the living room, while it pass through electrical outlet in the bathroom.
According to science, air move from the high pressure to the low pressure area. So that all of air move from the ground level to attic by using recessed light in the kitchen and bathroom, and using attic hatch in the living room. Moreover, bathroom fan vent and plumbing fan vent are used by air to get out of the building.