Dr. Weil teaches courses in energy efficient buildings. With primary responsibility for the Extension program in building energy, his research program is responsive to the needs of various stakeholders in the Commonwealth of Massachusetts, including home builders, architects, weatherization companies, energy utilities, state government agencies, town governments, environmental and community organizations, and homeowners. He is particularly interested in the social and behavioral dimensions of energy efficiency. He is a building analyst certified with the Building Performance Institute, and continues to enjoy building diagnostics. He manages the online Green Building Certificate for the BCT program.