Buildings dated between 1950 and 1975 were constructed in an era where energy efficient performance was not a critical part of the design. Many of these buildings now require the retrofit of exterior pre-fabricated concrete panels, and an opportunity exists to ensure this occurs utilising the latest technologies to improve energy efficiency. IMPRESS has leveraged on the potential of offsite manufacture for prefabrication by developing a new range of easy to install panels. Three different prefabricated panels for buildings have been developed: (i) a polyurethane based insulated panel for overcladding (ii) a thin, lightweight pre-cast concrete sandwich panel for over-cladding; (iii) a lightweight sandwich panel incorporating Phase Change Material, for re-cladding. Innovative nano/micro particle based coatings, suitable for 3D printing, have also developed to achieve anti-corrosion resistance, high mechanical strength, improved solar reflectance, and improved ageing resistance. To create the panels, an innovative manufacturing process has been created that includes Reconfigurable Moulding (RM) techniques, 3D laser scanning and 3D printed technology. The overall manufacturing process allows allow for mass production of panels, increases the speed of production and gives new controlled and cost effective solutions. Improved methodologies and systems have been created and the project has produced decision support tool for the design stage of renovation to allow the end user to choose which re-cladding/over-cladding option is suitable for their building. A new BIM based Iterative Design Methodology has been produced which incorporates all stages of the design - install - operate process, and has been integrated in an online management platform as well as backed by a cloud based BIM database focussing on the interoperability between software tools required for the prefabricated process. The final results were demonstrated on two buildings where final as-built product performance was evaluated and the software and methodology assessed.