One way to have a green building is to make the building small.  This saves on heating and cooling costs.  I have seen living spaces for two on TV as small as 70 square feet.  One way to make living in a small space function is to have more than one function for the space.  For example using a laptop at the dining room table rather than having a whole separate desk with a pc.  In my family four of us and a dog live in 650 square feet.  It is small but we save a lot of money and live simply.

The reason for building greener homes is very important because the degradation of our environment is compromising not only our survival, but the survival of most other living beings on the planet.