In this historical period of abrupt growth of the cities, with globalized networks of human settlements and infrastructural configurations (Brenner, 2014), this kind of architecture is the answer to the overpriced cost of dwellings of the city. Most of all, what is interesting, it’s the human natural propensity to set up communities even on a strange location as a roof.

This unique and bizarre urban development inspired this research, that aims to find new solutions for an alternative development of hyper-dense cities, using roofs as new ground 0 for the urban community growth. Thinking of a roof as a new habitat for the public sphere (Fraser, 1993). That’s a step forward compared to what we expected to find. We were looking for the reason behind, we found, intrinsically, a way forward another kind of development. Therefore, this thesis started from a deep analysis of how globalization influenced the urban development of the main cities of the world, focusing on three Asian trade ports, including Hong Kong, who are continuously re-shaping themselves due to unceasing immigrants flows and business investments.

In particular Hong Kong, at the center of the debate on urban development, it’s a mixture of top-down planning and bottom-up informal activities(Frampton, 2010), that unfortunately is facing a series of redevelopments of historical urban areas that are increasing gentrification at the expense of community heritage. Wedding Card Street and Langham Place are some cases that influenced this debate.

Despite these events, community is constantly re-shaping its boundaries, finding always unexpected developing solutions. You can understand a lot of Hong Kong people by looking at the use of residual spaces as sidewalks, causeways, high rise buildings canyons and, obviously roofs. These spaces are the soul of the public sphere and sense of community in Hong Kong. Between these solutions, roofs are those having a better outlook for future. In a future of increased building density, the current ground floor, concerned as base of the ordinary urban experiences,(Crawford, 2008) could be shift on above high-rise buildings, opening to an innovative and alternative urban vertical expansion.

Consequently, the research concentrates on Kowloon City District, in East Hong Kong, where one of the most radical urban renewal projects of the city is under development: the Second Central Business District of Hong Kong. Beside this top-down process, in the same district, is located one of the poorest working- class neighborhood of the city, Ma Tau Kok. This area is an arrival station for immigrants and it is well-known for the presence of several informal settlements on roofs of old buildings, disparate ex-industries and for the lack of community gathering places. Thanks to its industrial background, this area is full of massive buildings with unused large flat roofs, that have been field for our rooftop community habitat.

Following a deep study of social needs, through interviews with population and local NGO’s, we defined, as urban planning methodology, a matrix of functions, starting from users requested goals and desirable scenarios. Throughout this methodology, linked to the analysis of each building of the area, regarding users, neighborhood, roof shape and potentials, we projected the community spaces of each roof in Ma Tau Kok.

Reconnecting to the research start point, the thesis ends with a detailed study of the roof vertical expansion of the “5 streets” rooftop informal village. Our project aims to find a solution to improve inhabitants lifestyle and community public sphere, through innovative entrepreneurial solutions.

This thesis aims to criticize the usual top-down urban planning of such a global city as Hong Kong. We propose a bottom-up solution, starting from population needs and cultural heritage of the city.

We introduce a community-based program for future urban redevelopments. We introduce maximum use of buildings, converting roofs to innovative community hubs. Our aim is to move from Roof to Ground...