The municipalities of Barendrecht, Albrandswaard and Ridderkerk (BAR) aim to be CO2 neutral by 2050. An important component in achieving these objectives is to encourage sustainable behavior among residents. The way people organize their lives within a household has a major impact on climate change (Dietz. et.al., 2009). Most people are aware of this information, but it still proves difficult to adapt their lifestyle to more sustainable behaviors (Lorenzoni, Nicholson-Cole, & Whitmarsh, 2007). How can municipal policy help households to organize their lives in a sustainable way, while at the same time doing justice to the diversity in society? This question is the driver of the research project 'Sustainability in the Home’ which is executed by the Erasmus School of Social and Behavioral Sciences. In this project we use different research methods: questionnaires, focus groups, ethnographic research and co-creation.

In this research project we opt for an analytical approach to behavior that does justice to the complexity of the context in which behavior takes place. We do this by studying 'Social Practices'. Policymakers often look for solutions from a psychological behavioral perspective, in which the motives (norms, values, motivation) of individuals take central stage. However, behavior is not linear and context matters. Social practice theory is based on the principle that everyday behavior is embedded in different (social) systems. Behavior is part of the patterns in which people shape their daily lives. Meanings, skills and materials play a role in these patterns (Brand, 2010). A relevant social practice to investigate is 'retrofitting', because making the home more sustainable can be part of this. Retrofit is a continuous process in which small or large physical changes are made in and to the home, in order to live there as a family (Judson & Maller, 2014). In addition to retrofitting, we choose a focus on food-related social practices. Food is in fact responsible for at least 21% of the CO2 emissions of an average Dutch household (de Valk et al., 2016) and there is a large 'hidden impact' (see illustration), and there are many links to policy themes such as ‘mobility’, ‘energy-use’ ‘recycling’ and ‘food waste’.