5-Star Rating
A 5-Star rating indicates that a building achieves a high level of thermal energy performance, and will require minimum levels of heating and cooling to be comfortable in winter and summer. Houses which achieve a 5 star rating, compared to the average 2 star home, should be more comfortable to live in, have lower energy bills, and costs to install heating and cooling equipment should also be lower.
Energy assessments take into account different climatic conditions in different parts of the country and are benchmarked according to average household energy consumption particular to a given climatic region.
The house energy rating does not currently include the efficiency of any appliances fitted or used within the house. There are also no physical testing requirements, so air tightness testing is not required as it is with the regulations in the UK.
Read more about this topic: House Energy Rating