Although refurbishment is a necessary step to reach the ambitious energy and decarbonisation targets for 2020 and 2050, which require an eventual reduction up to 90% in CO2 emissions, the rate of renovation is still relatively low. There is an increasing demand to upgrade both the physical condition and the performance of the building, with the minimum disturbance to the interior, so that the occupants do not have to be relocated during construction. Thus, the role of the occupant becomes essential not only in terms of performance during the post-refurbishment phase, but also in terms of the design and planning of the refurbishment. Furthermore, the traditional design and delivery processes are fragmented and are not efficient to take on the challenges ahead. To address these issues, the 2ndSkin-BTA project brings different stakeholder together, aiming at reversing the traditional decision-making process, to integrate their expertise and objectives into an innovate building technology concept. The objective is to design, construct and monitor a renovation project that achieves zero energy use of a dwelling, while providing upscaling possibilities and broad adoptability of the process. This paper presents the first project phase, which is the integrated design process. To this end, the development of the preliminary design of the refurbishment strategy is based on a reference building. It proceeds in parallel with the prototypes’ development and it benefits from the test results. Nevertheless, the proposed design is not a one-project solution but rather an approach that highlights the underlying argumentation line for different retrofitting measures, in different cases.