Idaho residents with homes built or under construction before 2002, or who had a building permit issued before January 1, 2002, qualify for an income tax deduction for 100% of the cost of installing new insulation or other approved energy efficiency improvements in an existing residence. Any insulation added must be in addition to, not a replacement of, existing insulation. Other energy efficiency measures that may be deducted are windows that are more energy efficient than existing windows, storm windows, weather stripping and caulking, and duct sealing and insulation.