There is currently no robust method to evaluate how building design affects our emotion. Understanding emotion is significant, as it influences cognitive processes, behaviour and wellbeing, and is linked to the functioning of physiological systems. As mental health problems are more prevalent, and exposure to indoor environments is increasing, it is important we develop rigorous methods to understand whether design elements in our environment affect emotion. Using virtual reality and controlling for indoor environmental quality, 66 participants were exposed to different enclosed in¬door room scenes, to understand if scale affected self-report, autonomic nervous system and central nervous system correlates of emotion. Scale did not modulate neurophysiological measures or self-reported emotion, but there were differences between resting state and built environment conditions in autonomic measures, power spectral density and frontal power lateralisation. This study provides a rigorous empirical framework for assessing the environmental impact of a design characteristic on human emotion.