Coatings and finishes in historic centres between tradition and modern times - bases for an action and preservation plan for the historic centre of Coimbra
During the 20th century, traditional constructive systems were gradually replaced by industrial systems. As a consequence, traditional construction techniques, in particular historical coatings and finishes, have been little by little falling into oblivion. Urban images of historic centres have therefore been rapidly losing their character. That is precisely what happened to the Historic Centre (HC) of Coimbra. It should be noted that the very nature of the construction means that the simultaneous implementation of both traditional and modern constructive systems is unworkable; as a result, one of the factors responsible for the loss of character of the urban image of historic centres is directly related to using modern techniques and materials in historic buildings. This seriously affects the ability to understand the urban image in historic centres. In order to address this problem, we believe specific tools must be created which may help overcome the traditional/modern dichotomy by combining traditional techniques with the wide possibilities offered by technological advances and thus achieve sustainability. Our project, which systematizes and furthers the exploratory work conducted in the HC of Coimbra, sets out to study and analyze its “epidermis”, i.e. the colours, textures, coatings, architectural surfaces and so forth which shape the urban image of old Coimbra. This analysis will be a working base to propose a methodology to create both a Colour Plan and maintenance and restoration actions in other historic centres. The study relates the problem of building coatings and finishes, from a historical perspective, both to their social and economic functions and to urban and heritage policies. It uses the architectural, urban planning, materials techniques and sociological analytical dimensions in an interdisciplinary methodological approach, and this is the key to the development of an action and preservation plan for historic centres. The combination of these different analytical perspectives is what makes this project innovative and will enable it to have a broad impact both on scientific knowledge and on urban and heritage management policies. According to José Aguiar, the 1980s and '90s “have seen an evolution in the approach to colour plan development. Rather than plans based on general rules, (...) there is an evolution towards detailed plans in which each building is a unique case, (...)". This was when the first urban planning laws arose which required a Colour Plan as an instrument of urban control. This author also states that “from the definition of abstract standards on colour, plans are evolving to an increasingly accurate control of how intervention is conducted by shaping, rating, defining and regulating project practices, as well as bringing them closer to models defined by the theoretical and critical frameworks of heritage restoration and conservation: rather than ‘Colour Plans’, we now have ‘Plans that regulate materials that provide colour’”. Therefore, this project sets out to identify and characterize the formal solutions and the technology and materials used in traditional coatings and finishes in the HC which can still be identified in the Architectural Heritage. This will enable it to create a working base to support the subsequent implementation of an Integrated Plan to Protect Traditional Coatings and Finishes – a Colour Plan – to facilitate and stimulate the preservation of cultural heritage. Research into the HC “epidermis” will help to define intervention criteria for image protection (traditional building coatings and finishes) and to disseminate information collected so that it can be used in future conservation and restoration interventions in historic centres in general. The technical studies will use macroscopic and microscopic analytical techniques, including analysis of chemical and mineralogical composition. The following techniques will be used: optical microscopy; micro-Raman spectroscopy (well established in this area of research); powder X-ray diffraction and colorimetric characterization and manipulation of hyper-spectral images, in order to characterize the pigments and materials used. This project could be an important contribution to the reasons underpinning the application of the University of Coimbra to de designated as a UNESCO heritage site, as well as supporting the future creation of an interpretation centre for historic coatings and finishes in the HC of Coimbra.
Faculty of Science and Technology - University of Coimbra; University of Beira Interior; Câmara Municipal de Coimbra; IGESPAR – Instituto de Gestão do Património Arquitectónico e Arqueológico
Francisco Miguel Pereira Brardo Ferreira
Joana Abrantes
Jorge Santos
José António Raimundo Mendes da Silva
Lídia Maria Gil Catarino
Paulo Peixoto
Paulo Torrão Fiadeiro
Pedro Providência
Tiago Duarte