Green roofs are a fundamental technology in the transformation of urban centers into more sustainable environments, with a positive impact on buildings, cities, and their inhabitants. Yet, green roof technology may require the use of materials with a high environmental impact, namely, when associated with large transport distances. The present work arises from the need to find an environmental solution to use in an eco-school on one of the Azores islands. It tests green roofs on a wooden structure using local and sustainable materials. Prototypes were built to monitor their performance and to complement the theoretical information investigated regarding the construction systems of green roofs with alternative materials. The installation of the prototypes was accompanied by the school community, and the performance was monitored. The pumice stone proved to be an efficient solution for the drainage layer of the green roof. The use of local soil (volcanic origin) instead of a commercial substrate proved to work properly, both for drainage and for vegetation growth. Finally, the results also contribute to a better understanding of green roofs on wooden structures and encourage the use of local materials in future projects, with a view towards a circular economy.
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