This report contains the graduation project of Linde de Jonge in collaboration with Paviljoen 3, and aims to find a solution to reducing the eco-footprint of existing homes, by combining solar panels, green roofs and heat pumps in a modular fashion to be adaptable to the specific requirements of each household and complement the working of each individual system. Method User research, market analysis, creative sessions and observational studies have been implemented to support the iterative process towards a solution. The creative process was divided in three cycles. The focus of the first cycle was to find a solution with high feasibility for the company, by combining products on the market and adding small but crucial design intervention to create a unified system for flat roof surfaces. The second cycle aimed to create a solution suitable for tiled roofs, which is exceedingly common in the Netherlands, yet thus far incompatible with a green roof. The focus was on creating a solution which would enhance the exterior of the building, to increase the desirability of the design (an opportunity based on client research). The two cycles resulted in two concepts with a very opposing solution approach. These concepts were presented to the company and a selection was made. This selected concept was the start of the third cycle. In this cycle, the feasibility is established by detailing the embodiment of the system. Furthermore, the viability is illustrated by a future development roadmap. Design This project’s main challenge can be summarized as finding the balance between: 1. introducing an entire roof-system to market; 2. without losing the flexibility in the wide range of products (PV, heat pump or green roof) available to fit the variance in client and household needs; 3. and with the least amount of in-house produced parts to fit the company’s resources. The solution of this project is an entire roof-system, consisting of market available components and components proposed to be developed and manufactured by the company Paviljoen 3, which are implemented into the system according to distinct development phases. By combining existing products on the market, solely introducing components which are crucial for the viability of the roof-system and separating the innovation of system’s components into separate phases, this solution diffuses the investment costs for P3, while enabling them to acquire empirical insights concerning the system, which they can apply in further system development. They can have intensive prototyping and experience using market-bought products, before they invest in launching their own product. The design cycle ends with a final prototype of the developed components, and a company evaluation. The report concludes with a list of recommendations for the company to pursue further concept development.