People building their own houses have, at least theoretically, substantial autonomy when choosing, for example, a heating system and windows. In this article, focus is on the process of building new single-family houses and how energy efficiency and energy-efficient technology are incorporated into the building process. The conclusions emphasize energy as only one factor in housing purchase decisions. It is a big challenge to make low-energy building important to consumers. Consumer preferences for new products are unlikely to fully develop unless individuals have the opportunity to interact with them. It is difficult for consumers to know what to ask for if they lack experience of energy-efficient technologies. In the studied cases, the building codes and established standards became extremely decisive for how energy issues were included in the process. There is a need to change the design of incentives so as to make the least energy-efficient choice the most expensive. The most energy-efficient solution should be standard, and if the buyer wants to depart from that standard and build using less energy-efficient construction, then that should cost more. (C) 2013 Elsevier Ltd. All rights reserved.