Abstract
The new urbanism movement has repeatedly stressed the importance of dimensions such as density, land use and passive solar design in urban sustainability. However, little is known about lay people's conception of these constructs. If the urban environment is to be designed to prioritise people, understanding how they conceive of sustainability becomes important. The present study investigated lay people's conceptions of sustainable urban design by asking them to build their own cities with the urban simulation Sim City. In a balanced within-subjects design, participants were asked to create both the least and the most sustainable city they could imagine, whilst expressing their thought processes in a recorded think-aloud protocol. Transcripts were subsequently analysed for common themes which allowed for a comparison between participants' notions of sustainable urban design features and those identified by experts (Jabareen, 2006). This is the first time lay concepts of sustainability have been assessed this way. Participants showed awareness of several urban form factors including compactness, diversity, density, sustainable energy and transport, as well as greenery and mixed land use. The results further suggested that laypeople place particular emphasis on urban design aspects such as energy and transport. A key novel finding was that laypeople also include non-urban design aspects, such as education about the environment, in their notions of sustainability. These findings suggest there might be both mismatches and overlaps between expert and lay concepts of what a sustainable city entails, which in turn might help explain certain failures to engage with sustainable built environments.