This data was collected as part of a continuing collaboration between the University of Bath and Bath and North East Somerset Council, exploring the impacts of (and reception to) pioneering sustainable planning policies for new buildings which were first introduced in January 2023. This project evaluates the success of the policies two years on, establishing long-term trends, opportunities for refinement, and the national policy implications of this unique policy case study. The deposited data relates to two parts of the methodology. The first is an analysis of incoming planning application, relating to the characteristics of proposed buildings and key parameters submitted to comply with the net zero energy requirements. The second is the results of a questionnaire sent out to applicants.