From the NYT Sunday Magazine (How to build ...):
If the greenest house is no house at all, what's the next best thing? For homeowners like Tony and Sally Grassi, ecologically responsible construction isn't just about minimizing the immediate impact on the environment (their new 3,000-square-foot house in midcoast Maine was built on the site of a small hunting lodge) or energy consumption (photovoltaics, or solar panels, will supply some of their energy needs). It's about materials, especially plastics, adhesives and additives.
Wouldn't a greener house be 2000 square feet, instead of 3000?