Science and Innovation

Pere Joan Ravetllat Mira is an architect from the Escuela Técnica Superior de Arquitectura de Barcelona (ETSAB) and full professor at the Department of Architectural Projects of the Universitat Politècnica de Catalunya (UPC). With a long career in applied research, he is the coordinator of the REARQ group, dedicated to the rehabilitation and improvement of vulnerable residential environments and built heritage. He has led innovative projects such as COHAB-Raval and ‘Rev-Ter: Reviure els terrats‘ (project funded under the 2021 call for Research and Innovation projects), focused on sustainability, accessibility and improved habitability. His work emphasizes collaborative processes, ecological solutions and interventions adapted to social needs.

What lines of research are currently being developed in your field? What impact do they have at the local level?

The REARQ research group focuses on two main lines: intervention in vulnerable residential tissues and intervention in built heritage. We propose functional and sustainable improvements to increase the quality of life, especially for the most vulnerable groups, and we work on historic buildings to establish intervention criteria adapted to their complexities. These lines have a direct impact in Barcelona, improving living conditions in areas such as Ciutat Vella.

In general terms, two main lines of specialized research can be traced from the Architectural Rehabilitation and Restoration or REARQ group that I coordinate at the Universitat Politècnica de Catalunya.

Firstly, within the line of intervention in vulnerable residential fabrics, the multidisciplinary and transversal integration proposed by REARQ aims to establish processes aimed at the functional, sustainable and social improvement of housing in our environment, allowing progress towards a better quality of life and health, with special emphasis on the most vulnerable groups.

On the other hand, we work on the intervention in the built heritage. In this sense, we propose to intervene at different scales in the built heritage, from isolated buildings to built ensembles or systems that, due to their complexity or difficulty to address, remain without adequate intervention criteria.

Focusing on the project ‘Rev-Ter: Reviure els terrats’, what are its precedents?

The main precedent is the COHAB-Raval project, of co-design and co-manufacturing of solutions to improve the habitability of communities in the Raval neighborhood, promoted by the BIT HABITAT Foundation and developed during the year 2021. A good part of the team of that project collaborates in this initiative.

Based on the group’s previous research and the knowledge of the entities involved working in the field, for the first time we sought to materialize some solutions in the form of low-cost prototypes that we built in the common spaces of five different communities. In this work we realized the opportunities that this model of collaboration and applied research opens up, and we decided to seek funding for a new project to explore in more detail solutions for the rooftop space, which we have been able to see is a key space in Ciutat Vella.

What goals did you set for Rev-Ter?

As a main objective, we set out to design and prototype different low-cost solutions with quick and easy construction that would respond to the needs of use and improvement of the rooftops of Ciutat Vella. To do so, we proposed a broad socio-spatial analysis of the different neighborhoods and some buildings, and raised the possibility of building these prototypes in a pilot community.

How did you conduct the research, what did it entail?

It consisted of an extensive phase of characterization and approach in the neighborhoods from different perspectives, focused on the space of the rooftops, the use that is made, the needs of the communities that can be accommodated in these spaces, and their perception of it. In this phase, we have also elaborated very detailed descriptions of different rooftop spaces both at urban scale and in detail, taking some pilot buildings that we have visited, inspected, analyzed and drawn from the proximity.

Then, we have started a co-design work with two communities of neighbors, one of them in the Raval neighborhood and the other in the neighborhood of Sant Pere, Santa Caterina and La Ribera, to build two prototypes on their rooftops. This process has been accompanied by an investigation of constructive solutions and materials that are ecological, more efficient, that allow their ‘dismountability’ and are recyclable.

Finally, we have built two complete prototypes, with different elements (gazebo, platform, cabinets, planters, railings, sunscreens, clotheslines) for each of the communities, according to the needs expressed by the neighbors and the opportunities and shortcomings of each of the intervened rooftops.

What was the citizens’ engagement in the project?

In the first phase of the project, we organized dynamics of participation and debate with different entities and working groups, neighborhood groups and organizations related to the group of elderly people in Ciutat Vella. They helped us to make a more careful diagnosis of the needs and possible conflicts that are generated in the space of the rooftops, or the difficulties that can lead to intervene. The communities of the different buildings that we visited and studied in detail also provided us with valuable information for the study.

Finally, in the co-design and prototyping phase, we have held different meetings and participation sessions with the neighborhood communities of the two buildings where we have ended up building the prototypes, as well as training and celebration sessions once the project was completed.

Which were the results obtained?

From an analytical point of view, we have obtained different approaches, from a global scale of the whole of Ciutat Vella and the sociodemographic and socio-spatial dynamics that occur and that have an impact on the group of elderly people, the neighborhood communities in general and the use they can make of the rooftops. Aspects such as the lack of elevator, the lack of outdoor spaces and the small size of the dwellings, among many others, take on significant relevance.

At a more detailed level, we have been able to highlight the great richness of rooftop spaces. We have characterized some of the most common deficiencies that occur and that have a significant impact on the state of conservation of the building, but above all, on the possibilities and safety in the daily use of the roof space itself for leisure activities, care and relaxation by the community of neighbors.

Although some rooftops are in very good condition and the space is large enough to accommodate different uses, they are often not at all equipped and pleasant due to the lack of shaded areas, storage elements, or protective elements such as railings. The main improvement strategies have to revolve around: health, safety and risk prevention, durability, accessibility, environmental comfort and energy savings, and noise protection.

Through the participation sessions with different organizations and groups, as well as that expressed by neighbors of different communities studied in more detail, it is clear that the main problem in the use of rooftops is the difficulty of managing access and usage habits. Reluctance due to doubts related to maintenance and long-term conservation also have an impact. In this sense, encouraging meeting spaces, providing tools for community management and collective appropriation of shared spaces, and providing training on use and maintenance habits can be very positive impulses.

And how are these outcomes put into practice?

On an experimental scale, the main results of the project are set out in a Catalog of improvement solutions, which is structured on the basis of a list of needs and potential uses. The catalog includes from simple or partial interventions (railings and sills, ramps, surfaces and pavements, planters, furniture, clotheslines) to more global interventions (gazebos with floating pavement and integrated mobile elements). All of them can be disassembled, built with recyclable materials, low cost and simple and fast construction.

The catalog of solutions is also presented through their application on previously characterized and diagnosed case studies, where it is easier and more graphic to understand the potential and variability. The agreement with two pilot communities and the construction of two complex solutions with gazebo and multiple elements (planters, ramps, railings, floating pavement, etc.) are the final result that culminates the project.

What are your conclusions?

The project has allowed us to build a knowledge base around the rooftop space in Ciutat Vella from a socio-spatial perspective that can be very useful. In addition, it has provided a catalog of architectural proposals for the equipment and improvement of these spaces, and has explored their materialization through two prototypes. This theoretical-practical exercise with an enormous local social commitment opens different ways of continuity, around the reflection on how to improve the rooftop space on a global scale and the prospecting of practical implementable solutions.

The rooftops are underutilized spaces, with a huge potential for use that happens to have elements that support the community appropriation of these spaces that enjoy a great quality in one around high density of uses and population, and in buildings where the rest of the common spaces are very small and do not give place to the meeting and being.

There are different technological and architectural possibilities for improvement that do not compromise the state of conservation or the long-term durability of elements such as the current flooring and waterproofing, and that can be very useful to equip, make these spaces more pleasant and more comfortable.

The systems developed can start from very simple elements and end up articulating more comprehensive solutions, are low cost, recyclable and fully removable, a fact that guarantees efficiency in the short and long term.

What would you say are the social implications of these results at the neighborhood, district, city, metropolitan area, etc. level?

Solution-oriented research for the improvement of living conditions in existing buildings is a field that has a long way to go, because the need for improvement is enormous. In existing multi-family buildings, especially in disadvantaged areas where the dwellings are small, there is a lack of outdoor spaces (both in the building and in the neighborhood in general), and community spaces are of great importance.

Rooftops, which are outdoors, can also contribute to the renaturalization of the city, the improvement of environmental comfort, and the recovery or articulation of forms of socialization and neighborhood that have been lost or have not yet taken place, offering more comfortable and pleasant environments, as well as horizons of more community coexistence.

This type of approach can be oriented to other neighborhoods with similar conditions, especially underprivileged neighborhoods with a type of multi-family buildings of a certain height with walkable roofs. These situations are very frequent in different neighborhoods of the city of Barcelona and its Metropolitan Area.

Then, what are the new challenges posed by these results and what role do citizens, administrations, companies and other organizations play?

The challenge of improving the habitability of existing multi-family buildings is enormous and involves multiple agents, from the public administration to the third sector, applied university research and citizens. Community spaces are halfway between the street, squares, parks and housing. They are often more generous and offer opportunities that housing cannot cover, especially in terms of outdoor spaces for tranquility, silence, naturalization and also socialization with the neighborhood.

This is a challenge with architectural and technological implications, but in which community management is of paramount importance, which must be promoted by citizens, neighborhood communities, neighborhood organizations and entities, property management companies and the administration.

Will this line of research continue?

The research groups are involved in different projects linked to the improvement of habitability conditions in existing buildings, and continue to collaborate in this line through multidisciplinary teams, as well as with the local entities involved in the project.

Throughout this year, the satisfaction and use of the prototypes implemented in the two pilot communities will be monitored, and some training sessions will continue, both in the field of systems and materials maintenance and community management.

Collaboration with local companies in the construction sector and with neighborhood organizations should allow replication of the solutions proposed and included in an openly published catalog in other neighborhood communities.