Retrofit Plus project comprises of a holistic package of approaches designed for increasing trust, quality and performance, and reducing the price of retrofit. The approaches include rapid assessment using dynamic simulation tools; an expert system for zero carbon solution design; off-site manufacture of insulation panels so as to minimise on-site time, reducing inter-skill barriers, and disruption to householders; ease of disassembly for adaptation to climate change and for ultimate recycling; continuous predictive control and monitoring; smart phone interfaces for real time user feedback; game technology that encourages competition in energy savings between individuals; and after care portfolio monitoring and pre-emptive and rapid response to performance problems. The project facilitates experimental investigation of different solutions for 100% carbon emissions reduction and end user engagement and change of behaviour. Combined under a new business model, the project is designed to unlock the market potential and deliver substantial scaling up of retrofit.