Even buying an ordinary house seems to be an enormous maze when considering all the emotional, financial and legal issues. Let´s assume that you are not a “green energy” engineer with experience in doing home inspections, then not many of us have experience with buying a zero energy house. We are all first time buyers.
The easiest way to start is to check whether the house is recognized as a zero energy home by the U.S. Department of Energy’s National Renewable Energy Program. It is very important to hire a home inspector, preferably an engineer with experience in doing zero energy home or green home inspections. He has to make sure that the house is well insulated, has energy star rated appliances, sufficient power sources (photovoltaic or wind), and energy efficient cooling and heating systems.
Do not look for retrofits! A true zero energy home have to be designed and built from the ground to save and produce energy.