In order to develop the concept of sustainability in the built environment there must be increased use of detailed predictive tools, both at an individual building level and at urban scale. A number of tools exist for predicting the energy and environmental performance at an individual building level. However, there are few tools available to predict performance at an urban scale. This paper describes the Energy and Environment Prediction (EEP) tool which was developed to model existing urban scale built environments, incorporating building energy use, traffic flow and health.