This article considers how teachers' encounters with a newly built learning space are complicit in the practices performed in that space. It builds on previous research into the relationship between learning spaces and pedagogical change by highlighting the acoustic aspects and how they were perceived by teachers in a primary school. Over two phases of the study, teachers and the principal were interviewed post occupancy to gather their perceptions and experiences of the learning environment. These interviews were analysed as evidence of practices and cross-referenced with the acoustic assessments which were conducted in each phase. The results show that, because of the salience of teachers' perceptions and experiences of the acoustic environment in their pedagogical practices, this aspect of school design needs to be more clearly considered. The study also highlights the importance of teacher's voices so that their situated pedagogical knowledge is taken into account.