Fionn is Professor of Sustainable Design at the University of Sheffield, and Director of Technology in the School of Architecture. She manages research within the Architectural Science group, which has carried out a wide range of EU and EPSRC research projects, as well as government funded research contracts and consultancy related to sustainable buildings. The group has an international reputation for lighting, acoustics, building occupancy performance and feedback research.

As a chartered architect, educator and researcher she has a profound understanding of environmental and ecological issues as they impact on the construction industry, architectural education and practice.