The origins of art and architecture are not properly understood. Research in to the evolution of art has been concerned with function with respect to survival. Art appears to have no survival function, in that creating beautiful works requires practice and time which might be better devoted to gaining food. Architecture may function as a selected fitness indicator and the experience of beauty in architecture might be an adaptive mechanism to indicate who has the best genes. Fitness indicators are defined by being wasteful, in the Handicap Principle (Zahavi, 1975). This set of exploratory studies examines beauty in architecture, in two ways. Firstly investigating if individuals agree on what is beautiful and that building beauty is used by individuals to predict the good genes of a building's owner. The second part of the investigation set out to explain architectural beauty in terms of the wasteful aspects of ceiling height and wall thickness. It was found that individuals agree on what buildings are beautiful and that they can use this beauty to predict good genes related aspects of the owner. Wasteful buildings were found to be beautiful. These findings provide support for a theory of architecture as a fitness indicator.