A house doesn’t need to have solar panels, rainwater collecting system, or uses recycled materials in order to be considered as eco-friendly. The La Maison-vague by Parisian architect Patrick Nadeau is a good example of an eco—friendly house without the solar panels and other common eco-friendly items. The only thing that this eco-house has is the unique insulation it got, wherein it uses earth and a great selection of plants. The house structure is made of wood, which is known to be a sustainable material as well. With this type of insulation, residents can save much on energy for their air-conditioner or heater.