Tightly regulating indoor building temperatures using mechanical heating and cooling contributes significantly to worldwide greenhouse gas emissions. One promising approach for reducing the energy demand associated with indoor climate control is the adaptive model for thermal comfort. In this paper, we explore the challenges and opportunities for supporting the transition toward adaptive thermal comfort in conventionally heated buildings. We replaced the heating control system for eight university undergraduates living on campus for fifty days from January-March 2013. We report on the participants' experiences of living with and adapting to the change in conditions. We reflect on the lessons arising from our intervention for researchers and practitioners seeking to design for sustainability and thermal comfort.