96 Israel Nagore Setién I Londres, Reino Unido TOWARDS AN OPEN AND USER DRIVEN HOUSING ARCHITECTURE Layers principle, infrastructure types and technical devices Departing from John Habraken theories, this paper puts forward a study on the design opportunities that the separation Support and infill offers, by means of a thorough examination of the infrastructure concept. By means of the analysis of open building projects, it is proposed a study of the different levels of the infrastructural design, developing a catalogue of technical devices running through the scales of the infrastructure 1 . It is intended to develop a set of strategies and solutions, conceived under the premise of understanding the dwelling as an open system –able to change over time-, which facilitates the user appropriation and participation. SUPPORT AND INFILL. OPEN BUILDING PRINCIPLES In 1962, dutch architect N.John Habraken published the seminal book De Dragers en de Mensen, translated and published into English as Supports: an alternative to mass housing. At that time, Europe was going through a major housing shortage because many buildings had been destroyed during the World War II. Habraken’s text is a critique of the repetitive, massive, homogeneous constructions built in the postwar era to alleviate this shortage. The plot of the book is developed from a fundamental question which remains in effect. According to Habraken, the main problem of residential archi- tecture is that it is built for people, who will never have the slightest chance to make basic decisions about their living environment. Against the idea of a house as a consumer, repetitive and finished product, Habraken proposes the concept of house as a process. A dwelling is understood as the relation- ship of the dweller with his environment, a natural relation based on the acts of our daily lives and it is deeply rooted in the foundations of our existence. However, the book is not limited to expose his censure, but includes a specific proposal as alternative. This proposal is based on identifying two levels of control in a collective housing building; the act of building and the act of dwelling-, separating what remains, the collective part controlled by the community; – which depends strictly of the regulations, structure, and installations -, the “base building”, from that which can be transformable and can be adapted to suit the user, like the interior divisions, closets or kitchens and bathrooms, the separable units or infill 2 . Habraken’s support and infill separation, is part of a broader reflection on our cities and territory. Our built environment is a live organism, a never ending changing process driven by rules and principles difficult to control and predict, which serves to our needs thanks only to its continuous adaptation and transformation. Open building principles 3 , are based on the perception of this built environment as a multi-layered structure, where five primary physical systems are recognized. Within a city, we can identify the urban structure, the urban tissue (blocks), the buildings, the infill components and the actual furniture. Each of these systems has a different life span and is related to different levels of control and responsibility –different agents acting on each level-. Our built environment is sustainable to the extend that each system is transformed independently and part by part. In short, architecture is understood as a system formed by subsystems, part at the same time of larger systems 4 . 1 The content of this paper synthesizes the findings of the MA by research Open Building in the collective housing of the 21st century. Possibilities and limitations, carried out at the Kingston Faculty of Architecture (2010-2011). As part of that research, sixteen Open Building case studies were analysed. 2 Habraken, Nicholas John and Mignucci, Andres (2010) Soportes: Vivienda y Ciudad. Instituto de Arquitectura Tropical. Editorial on line. 3 The Open building organization, created in 1992, receives the theoretical legacy of Habraken and the SAR. Nowadays is a network of initiatives dedicated to the implementa- tion of these principles. 4 Habraken & Mignucci (2010). 1. TEORÍA, HISTORIA Y PROYECTO