The Comprehensive Assessment of Systems for Built Environment Efficiency (CASBEE) for Home is the first national voluntary Green Building Program for residential structures in Japan. The effect of builder demographic factors on the adoption of the CASBEE for Home program were investigated since the success of CASBEE for Home will be heavily reliant on the usage of the program. In this study, the adoption of the CASBEE for Home program by home builders is modeled as a two-stage process with builder awareness preceding the actual use of CASBEE for Home. The results show that both firm size and the type of homes built influence Japanese builder's awareness of the CASBEE for Home program. In addition, respondents who had participated in the 200-Year House Program, another voluntary program, were significantly more likely to use CASBEE for Home. Finally, the number of years a builder has been in business both increased their awareness and usage of the CASBEE for Home program. Our results suggest that the likelihood of adopting the CASBEE for Home program was influenced by the internal resources available, the type of customers being served, and the business experience of the firm.