There are lots of ways to build “green” today. There are a number of different “green” certification programs out there to evaluate your level of “greenness” like EarthCraft VA, LEED, NAHB Green, Passive House US, The Thousand House Challenge and many more. All of these different certification programs have different ways to certify your level of “greenness” as well. With so many people today claiming to be “green” what is the best way to cut through all of their claims and get to the bottom of who is really “green”?
First we have to define what green means. It can be defined differently by different people. I think that adding cool technology to your house is a great step forward, but adding solar panels to a ginormous, energy leaking house and calling it green would be a bit of a stretch. So when it comes to rating a house as “green”, the basic definition would have to be a house that has a smaller carbon footprint than a typical code built house. The smaller the carbon footprint, the “greener” the house. What is a carbon footprint? Even this is difficult to define. Wikipedia says that your carbon footprint is the total amount of greenhouse gases emitted from a person or activity, or in our case, your house. Some could rightly argue that just looking at what greenhouse gases are emitted by the day to day operation of your house would be a very simplistic calculation because it does not take into account embodied energy. Embodied energy is a whole other ball game, and if you would like an absolutely great and humorous explanation of it go to https://www.ted.com/talks/lang/en/catherine_mohr_builds_green.html.
To make the definition even simpler, I am talking energy usage. At the end of the day, a house that claims to be “green” should use less electricity and propane or natural gas than a house that is built to meet today’s building code. It could be filled with recycled materials and locally sourced amenities but what good does that do the environment if your house burns the same amount of electricity or even more than the standard house down the block.
So how do you tell? Ask to see the utility bills. Of course you have to be careful that you are looking at utility bills for the house while it was occupied and not while it was sitting empty and for sale. Utility bills are a good place to start, however, sometimes it is hard to compare apples to apples. One house for sale might have Sam and Suzy Sustainability living there who use keep their thermostats set high in the summer and low in the winter and they use almost no water. The next house you look at might have Gerry and Glenda Glutton living there with their 6 plasma screen TV’s that are on all the time. The difference in the utility bills could be due to personal lifestyle choices and have nothing to do with the houses themself.
The problem here is determining how well does the house actually perform when it comes to energy usage? A new way to help homeowners gauge home performance is to rate each house using the same rating system and then publishing that information in a way that is easily accessible when you are making a home purchasing decision. The future of making energy efficiency decisions about houses is having the houses HERS index rating score published in the houses MLS (multiple listing service) listing. The HERS rating is established by a third party so you don’t have to worry about the builder or the homeowner implying that the house performs better than it actually does. Nothing gives you better information when making a big purchase like a home than a HERS rating and nothing would make it simpler to shop for a house than to have that rating published with the sales listing in the MLS. But in the end, I still tell people to ask for the utility bills.
When making a decision about the biggest purchase of your life, it helps to have something visual, like a HERS rating score, to help you compare performance. I read of one builder in San Antonio Texas that wanted to give people a cute visual of how energy efficient his houses were so he puts a chocolate bunny in the attic of every home he builds. In Texas yet! An un-melted chocolate bunny in the attic in summer in Texas speaks volumes. So when shopping for a new home either ask to see the utility bills and the HERS score or carry around a chocolate bunny with you. You decide.