Correzioni urbane nei centri storici tedeschi. Proposte per il centro di Lubecca

Talking about a new Bauhaus implies asking what this novelty consists of and what distinguishes it from the original school (1919-1933). Of which, today, we must be aware of the limitations of its teaching, especially with respect to the notion of Heritage of the historic European city. After the losses suffered from wartime destruction up to the radical reconstructive interventions of the 1960s and 1970s, we have gradually become aware of such heritage. Where, this awareness is not intended only in terms of protection and preservation, but also as a constant reference for designing on its fragmented condition. To decipher it, we use an archaeological approach, based on the analysis of different temporal layers. The iconography of its urban image becomes a useful tool to select what to preserve and what to replace. To understand the methodological basis adopted here, it is necessary to refer to the debate on historic centres began after World War II when, for the first time, the loss of the centre and the need to restore a heart to the city became a central topic debated by historians, architects, and town planners. The critical revision of the functionalist city and the consequent development of tools for urban analysis contributed to the investigation of the morphological structure and typological characteristics of historical cities. With the kritische Rekonstruktion – born at the end of the 1970s and later put into practice by the IBA-Berlin – the layout of the historic city became a concrete model of comparison from an operational point of view. From here derives a participatory awareness, in which citizens and different kinds of specialists have been involved. In that sense, the reintegration of the intrinsic qualities of the historic city as urban artifact is not intended as nostalgic research of a lost past, but as a real necessary implementation with respect to the current demands for sustainability. Research on the urban form is at the heart of recent reconstruction projects for the old centres of German cities, including Berlin, Dresden, Frankfurt, Potsdam and Lübeck. A research based on the elementary principles of the single plot and the individual house as the minimum units on which to build the structure of urban blocks and the form of collective spaces. A form that refers to the collective memory of the historic city, whose legacy has been transmitted over the centuries through the figurative heritage that has come down to us. The conscious desire to reclaim this image has led to strategic operations of urban correction. These require the substitution of previous interventions, extraneous for their morphological scale and their typological-constructive choices to the historic fabric once present. The characters of residence in German historic centres are defined by settlement forms and building types. Not only typological-morphological characters, but also formal and constructive ones distinguish the historical German house as a minimal building element of the urban layout, differentiating it from those of other countries. In the specific case of Lübeck, its urban image is the result of a progressive construction process over time, based on the permanence of the parcelled layout of blocks. The side-by-side block house type has survived over the centuries, despite various stylistic and architectural variations. The ongoing renaissance of the Gründungsviertel – the old Founder’s District in the central site between St. Marien Church and the Trave River – has been realised in the spirit of critical reconstruction. Based on the shape of the historical parcels, the available plots have different sizes, thanks to which the richness and variety of the past urban image can today be reproposed under new forms. It is precisely from the study of this recent realisation that the didactic projects presented here – carried out at Politecnico di Milano (Proff.: A. Burg, M. Caja, 2020-2021) – take their cue, to find guidelines and architectural references to refer to, albeit critically. The aim was to develop a common plan for the centre of Lübeck based on the reconstructive principles of the case studies analysed. Through replacement or in-fill operations, the plan intends to restore the original urban form, based on a careful analysis of the original plots structure. The first aim is to redefine the compactness and density of the original housing blocks and the close relationship they establish with the surrounding urban fabric. Other aspects relate more specifically to the morphological and architectural scale. In addition to residential use, public buildings of different sort have also been included to revitalise these central parts of the city.