New environmental challenges, coupled with the fact that 80% of the residential buildings that will exist in Europe in the year 2050 have already been built, mean that rehabilitation and restoration must be prioritised over new buildings. Construction is one of the largest generators of CO₂. Using prefabricated and industrialised products and systems can help to mitigate its harmful effects thanks to the greater control and environmental evaluation that can be carried out on these products from their manufacture until the end of their useful life (LCA). In the county of the Sierra de Cádiz (Andalusia, Spain), there are 85 water mills, many of which are derelict and in disuse, which, due to their location, size, and characteristics, are ideal for rehabilitation and restoration for residential use. Taking the “El Rodezno” mill as a case study, this paper proposes rehabilitation strategies using prefabricated industrialised elements that have a low environmental impact. The methodological discussion takes as its starting point the process of design and testing that Alvar Aalto applied in 1940 and from subsequent studies that have confirmed a research structure based on the project design and the built project with the appropriate field of study and confirmation of the applicable strategies and solutions. To this end, this article is written on the basis of the two main phases of Alvar Aalto’s method, using the same terms that the Danish architect defined: Scientific Observation, for the study of preceding works and projects in light prefabrication and for the analysis of certain construction products and systems that, based on other research, have evaluated their LCA, and Construction Period, for the rehabilitation strategies of the “El Rodezno” mill, considering the studies and analyses of Scientific Observation. For the roof solution, we took as an example the rehabilitation of the roof carried out with the same methodology, construction criteria, and prefabricated products analysed in this article and used in the intervention strategies in “El Rodezno”. The paper concludes with the validity of the methodology applied to test the starting hypotheses that lead to intervention strategies that confirm the environmental and economic advantages of industrialised prefabrication, the importance of the design and synergy that results from combining different construction systems, and technologies that improve the acceptance of prefabrication by the inhabitant and boost the circular economy.

RESUMEN La construcción exige conocimiento y ayuda a entender la lógica de la arquitectura por encima de los avances y descubrimientos producidos por ciencias, ingenierías e industrias. En cualquiera de las tendencias o movimientos que a lo largo del pasado siglo se han reconocido en arquitectura, técnica y tecnología de la construcción se han tratado como un aspecto esencial de su producción cultural y arquitectónica, y fueron usadas para indagar nuevas formas, nuevas arquitecturas, tratando de resolver una demanda social que no encontraba respuesta con los medios habituales de construir. El aforismo de Mies van der Rohe, “sólo reconozco problemas de construcción”, además de aludir a un momento en el que la industria estaba llamada a tener una participación decisiva en el futuro de la arquitectura, el sentido universal que encierra, revela que, la cuestión de la construcción en arquitectura, es una forma del pensamiento que afecta al proyecto desde sus primeros momentos. Quizá, por esta razón, muchas de las arquitecturas que visitamos o estudiamos, se preocupan profundamente por cual sería en cada momento, la mejor manera de expresar la condición constructiva de lo formado. SUMMARY: The construction requires knowledge and help to understand the logic of architecture over the progress and findings produced by science, engineering and industry. In any trends or movements throughout the last century have recognized architectural, technical and construction technology have been treated as an essential aspect of its cultural and architectural production, and were used to investigate new forms, new architectures trying to solve a social demand response was not the usual means of building. The aphorism of Mies van der Rohe, "I recognize only construction problems", and alluding to a time when the industry was destined to play a decisive role in the future of architecture, the universal sense it contains, reveals that, the issue of construction in architecture, is a form of thought that affects the project from its early stages. Perhaps for this reason, many of the architectures we visited or studied, care deeply about what would be in each moment, the best way to express the condition of the formed constructive

The catastrophic destruction of buildings in France during World War II demanded that reconstruction become one of the primary objectives in the immediate post-war period. This favoured a culture of experimentation, and created a context for Jean Prouvé to develop designs for school buildings. He developed these designs with a research-based process focusing on technical solutions and their prototypes, and with models whose fundamental premises were rapid and easy assembly-disassembly, lightness and economy. The constant correlation between the projected object and the object created in the workshop shaped the basis for the precision of his designs. This article analyses the methodology followed by Prouvé in the Jules Ferry School Group in Dieulouard, France (1952–1953), in the singular context of the post-war period, illustrating the route followed in developing the model rather than the aesthetics of the building. The prototype used in his schools, and the models generated from this system, demonstrate his architectural methods.

DE LA INVESTIGACIÓN, LA ENSEÑANZA Y EL APRENDIZAJE EXPERIMENTAL DE LA ARQUITECTURA / From research, teaching and the experimental learning of Architecure

This article reflects on the potential that old productive architectures have in activating rural environments. Despite their obsolescence, they continue to form historical, functional and explanatory networks of the territories, with potential for reactivation. It starts with an approach on the interest that traditional and vernacular architectures have generated since the 20th century. The current regional spatial planning applied to the Sierra de Cadiz and the water mills is reviewed. Their typological, functional and implementation characteristics are analysed. Finally, new scenarios are proposed that take into consideration the recovery of these architectures and the reactivation of their region.

RESUMEN Este artículo analiza la relación entre los viajes a Inglaterra de Manuel Trillo, el proyecto de viviendas colectivas en La Motilla y su investigación docente sobre vivienda y ciudad. La construcción del Edificio de Oficinas del Sevilla 1, obligó a Manuel Trillo en el año 1971, a realizar un primer viaje a Inglaterra descubriendo una arquitectura nueva y tecnológica. El interés por las teorías de Archigram, la arquitectura de Stirling y Alison&Peter Smithson motivaron, al poco tiempo, un segundo viaje. El aprendizaje que deriva de ellos, tuvo una primera consecuencia en las viviendas de La Motilla, trasladando a Sevilla modelos residenciales visitados en Inglaterra de los Smithson y de Stirling. La creación de ciudad con vivienda colectiva se convertirá en el principal campo de reflexión, investigación y práctica docente del profesor Manuel Trillo: desde la década de los setenta hasta sus últimos años en activo; en la escuela de arquitectura de Sevilla y en su breve pero intensa estancia en la escuela de arquitectura de Valladolid. En el año 2003, volverá a realizar un tercer viaje a Inglaterra; la historia parecerá repetirse, proponiendo de nuevo otras arquitecturas posibles para la ciudad de Sevilla cuando, al paso de los años, ni la tecnología ni la industrialización eran ya obstáculos para su realización.SUMMARY This article analyses the relationship between Manuel Trillo’s trips to England, the collective housing project in La Motilla and his academic research on housing and the city. The construction of the Seville 1 office building, forced Manuel Trillo in 1971, to make his first trip to England and discover a new technological architecture. The interest in theories of Archigram, architecture by Stirling and Alison&Peter Smithson motivated, soon after, a second trip. Learning that derived from them, had a first result in the homes of La Motilla, transferring to Seville residential models by Smithson and Stirling in England. The creation of the city with collective housing will become the main field of reflection, research and teaching practice of Professor Manuel Trillo: from the seventies until his last active years; in the School of Architecture of Seville and in his brief but intense stay in the School of Architecture of Valladolid. In 2003, he made a third trip to England; it seemed that history repeated itself, proposing new and other possible architectures for Seville when, over the years, neither technology nor industrialisation were obstacles to its execution.