This thesis offers a response to one of the most enduring housing challenges: how to secure capital that remains affordable for housing built for social purposes. To achieve this, it presents the first in-depth academic study of impact investing in social property, or impact real estate, focusing specifically on the case of Cheyne Capital, the London-based alternative investment manager, and its role in developing housing for disadvantaged groups.Looking at one of the earliest examples of impact investing, an emergent market not yet fully institutionalised, this research examines the mechanisms developed to create Big Society Capital, the world’s first social investment wholesale bank, and to introduce Social Investment Finance Intermediaries such as Cheyne Capital in order to build the modern social finance market for social and environmental initiatives. It further considers the challenges Cheyne Capital faced as a new social landlord, particularly those relating to inefficiencies in building procurement, the need to develop viable real estate schemes and the requirement to demonstrate measurable social impact alongside financial return for each investment.The case analysis reveals that it is possible to achieve a model in which the business model and the impact model coincide. The outcome is that Cheyne Capital has invested around £900 million in addressing the shortage of affordable housing, delivering key worker housing, supported living, extra-care housing for older people and housing for people experiencing homelessness in partnership with local councils, housing associations and charities. The thesis also introduces design principles and a prototypical housing module for housing without a site, together with an exploratory framework for social impact measurement. These findings offer insight into the opportunities, risks, challenges and policy implications of using this model to deliver affordable urban housing at scale.

Serena Lehua Jarvis completed her PhD at the Architectural Association. Before joining the AA, she graduated with distinction from the Bartlett with an MSc in Building and Urban Design in Development in 2011, receiving a special commendation for her dissertation. She has worked on one of the earliest impact-investing models in social housing as architectural consultant to the Social Property Impact Fund at Cheyne Capital. Her work examines impact investing, housing design and social value for disadvantaged groups.