IUMAT (Integrated Urban Metabolism Analysis Tool) is a system-based sustainability analysis tool. It quantifies and aggregates the social, economic and environmental capitals of urban activity in an integrated framework focusing on the metabolic flows of urban development. This paper builds on previous work on urban metabolism and advances an analytical framework that defines how the consumption of resources and resulting environmental impacts are calculated as indices of sustainability in an urban region. The benefits of integrated urban modeling using the proposed framework as well as the data sources are detailed. The underlying analytical framework for the proposed tool applies the dynamics of choice, time, and scale towards dynamically interpreting demographic and economic factors. IUMAT's calculative modules for land cover, transportation, and energy/water/resource use are described as well as the modality of connections between the modules.