The Dutch Energy Performance Standard (EPS) is a tool for quantifying fossil fuel use in the built-up environment. In contrast to the earlier EPC method, it can be used not only for individual dwellings, but also to calculate the energy consumption of an entire estate. By using standard assumptions about future residents' behaviour, a theoretical score on the EPS yardstick can be calculated, allowing policy-makers to set a cap on overall energy consumption at an early stage of planning. The original EPS system could be used for new housing estates only. In collaboration with DWA and Piode, CE has now developed a method for existing housing stock, which has been assessed by parties that will be using the tool. Particularly for large-scale renovation and restructuring projects, comparison of the EPS scores of the current and planned situation at an early stage will be very useful. This report sets out the details of the calculation method.