Create well-designed and well-built homes that cost less to live in, minimize damage to the environment and appreciate in value - those are the goals of a new research and design/build project at the University of Virginia School of Architecture.   Through ecoMOD - an innovative, community outreach program - U.Va. students and faculty will design and construct three 1,000 to 1,200 square foot prototype modular homes during the next four years.