This is a follow up of an assessment of a web-based, energy efficiency recommendation engine providing a customized “path to zero-net energy” for any existing home. This tool uses current technologies in building energy simulation and combines it in a novel way with other recent developments in 3D building data from aerial photography and cloud computing, to develop individual 'energy models' of each home. This project aims to assess adding additional energy use data and/or home energy audit information to the data set to improve the reliability of recommendations.