Home Buyers: What is HERS and Why you should care?

You may have seen a new line item in home listings nowadays that says HERS with a number next to it. The number is an index, meaning a relative score of how energy efficient the home is when compared to a standard home of same size built to local and national codes that has a score of 100. So, if the home you are looking at has an index of 70, it means this home is 30% more efficient than a comparable new home built to standard. A higher score, i.e. a number greater than 100, indicates that the home is less efficient than a standard new home.

How does it affect you? Well, it affects your bottom line at the end of the day. A higher score means your utility bill, especially for heating and cooling, will be much higher compared to a standard home. A lower score saves you money every month through the life of your stay in that home.

HERS IndexThe Home Energy Rating System (HERS) Index, in vogue since 1995, has become the industry standard by which a home's energy efficiency is measured. It’s also the nationally recognized system for inspecting and calculating a home's energy performance. A certified Home Energy Rater assesses the energy efficiency of a home, assigning it a relative performance score.

You have to be careful though, since not all homes are tested for the HERS rating. So, you may not see the score in many of the existing or even new homes. Many sellers and builders do not spend the money to get the home tested, especially when they know the home may not rate well, leaving you, the buyer, in the dark to bear the cost of higher utility bills.

Some builders call their new homes ‘green’ or ‘energy-efficient’ simply because they use slightly thicker insulation in the walls and ceilings. However, there's more to a home's health than insulation. A true energy efficient green home should be certified by agencies like EarthCraft or LEED. I will discuss why HERS is not the only thing you should be aware of in a home and why certification is important in my next article.

So, when you are looking at potential homes to buy or build, ask for the HERS index. If one is not available, ask if the seller/builder will test the home. When buyers start asking for the score, the sellers/builders will be forced to have their homes tested. This will encourage all builders to build their homes to higher standards than merely what building codes recommend. Remember, a code only indicates the minimum standard a home should be built to. There is no upper limit.

EarthCraft - http://www.viridiant.org/
LEED - http://www.usgbc.org/leed