ACI’s (Affordable Comfort Inc.) Linda Wigington was one of the speakers at the recent Passive House conference in Dutluth, MN. Her organization offers initiatives to improve the performance of homes. Linda introduced the crowd to what she calls “Deep Energy Reduction Retrofits”, an effort to help overcome the energy obsolescence of the existing housing stock in the U.S. To help with deep energy reduction retrofits and encourage people to start, ACI just launched the Thousand Homes Challenge. Take a look at ACI’s website. It is a great resource offering white papers and resources on how to do deep energy reduction retrofits.