SPR and RED sustainability were commissioned to anlayse the financial impact of potential changes to minimum energy performance requirements for new residential buildings. The project combined NatHERS thermal-shell modelling with Whole-of-Home energy and financial analysis for representative Class 1 and Class 2 archetypes, scaled using stock modelling to reflect ACT dwelling composition and construction forecasts. Scenarios tested a range of enhanced stringency settings against the NCC 2022 baseline, incorporating upgrades such as improved building fabric, higher-efficiency fixed appliances, rooftop solar PV, and batteries. Representative dwelling archetypes were modelled, with upgrades including fabric improvements, higher-efficiency fixed appliances, rooftop PV, and batteries. Sensitivity testing examined the impacts of future climate conditions, lighter roof colours, and different technology configurations on both thermal performance and cost-effectiveness.
Results were presented using a range of approaches, including benefit–cost ratios, net present value, and day-one bill-impact analysis, to meet the needs of diverse policy, regulatory and stakeholder audiences.The work showed that strengthened performance requirements can deliver improved household energy outcomes and emissions reductions while remaining cost-effective both a private and societal level, providing government with a robust platform for policy and regulatory decision-making.