"Envelope: The SAIC report derives most of its envelope-related savings from window replacement and roof insulation, assuming that only 1 percent of campus energy can be saved by weatherization. The report did not consider changes such as entry-way retrofits to reduce heat loss during entry and exit or improvements in insulation in areas besides roofs. Additionally, the report made no estimation of chilled water savings due to either weatherization or wall insulation, or any potential savings from decreasing heat gain through roofs due to improved reflectivity or vegetative roofs. Improvements to building envelope, weatherization, improving insulation levels in roofs and other areas, and tightening building infiltration and exfiltration would offer a 4 percent reduction in campus energy use, though more is highly likely. The campus target for envelopes is 1 percent."