An insightful, provocatively titled article from the 100K House blog addresses the importance of taking an integrated, holistic process to green building design, as opposed to the much more expensive approach of tacking on 'green' features to a poorly designed building:
In an interview a few weeks ago I was asked what our premium was for building LEED Platinum. The reporter had done some research and found that the highest level of LEED for Homes usually carried a 15-20% markup and wanted to know what the added cost was for our project. It was a difficult question since we don’t have a non-LEED version of the house with which to compare, but eventually I said, "Um . . . I guess . . . negative 5%"
Most of the builders and developers reporting high premiums for pursuing LEED are still trying to build the exact same home they have always built ... they polish the turd. Rather than redesign the house that has been successful for them in the past, they add solar panels, geothermal systems, high end interior fixtures, extra insulation and other green features. Since the features are add-ons and extras, the price rises as each one is tacked on.
To avoid these extra costs, one must start the home design process with affordability and sustainability factored into every decision.