A removable textile hybrid structural screen for the windows of Castello Sforzesco, Milan: when experimental metrics inform the bespoke ‘design-to-construction’ process in historical contexts

Abstract

This paper presents the completion of the experimental design-to-installation process of two textile hybrid window screens, aimed at mitigating the comfort conditions and preserving the frescoes of Sala delle Asse at Castello Sforzesco, one of the most important artefacts of cultural heritage in Milan.Given the historical relevance of the context, the main challenges that the project tackles are: 1) implementing bespoke, low impact, lightweight structural screens as reversible additions to historical buildings; 2) enhancing their performance in terms of visual, lighting and hygrothermal comfort; 3) then creating and validating an interdisciplinary methodology of managing the whole design-to-costruction process, with the aim to assess its replicability in other cultural heritage sites.The design task, led by Textile Architecture Network, at hand is to produce selfstanding vertical screens for the large-scale windows in the room, in order to control the sunlight amount on the frescos, as well as to block air drafts that cause humidity inside the room. The main challenge of the project proved to be the fragility of the direct context, since the screens must be sealed on the borders, but no perforations are allowed on the vaulted edges of the windows. Thus, a textile hybrid structure is proposed as a solution, made of : 1) bending-active and form-active elements, due to its self-standing principle that would not require drilling on the vault; 2) unconventional knitted textile materials, that need to be characterized both in terms of stretching properties and optical performances. Eventually the paper presents the preliminary multidisciplinary research campaign consisting of: 1) in situ anemometric tests by Experimental Mobile Laboratory; 1) material tests on optical transmittance carried out by SeedLab; 3) mechanical tensile tests and the updating of the material choices by Textile Architecture Network, all part of the Architecture, Built Environment and Construction Engineering

Textile Membrane for Façade Retrofitting: Exploring Fabric Potentialities for the Development of Innovative Strategies

“…The intervention accomplished at Sala delle Asse in Castello Sforzesco [26] demonstrates that textile solutions can effectively control the amount of daylight gains without completely preventing them. Moreover, thanks to their self-supporting ability, these solutions can reduce the need for additional anchoring supports, while still guaranteeing the same structural performance.…”