The Zero Carbon policy is intended to create a kind of ecological balance to neutralize greenhouse gas emissions. Several studies report that the construction sector is one of the main responsible for the unbalance in which we find ourselves today, after all, it consumes natural resources on a gigantic scale and still builds buildings that do not collaborate with the maintenance of the environment. Therefore, searching for paths towards a carbon neutral architecture has become fundamental and one of them is learning from past masters, such as the Brazilian architect João Filgueiras Lima, known as Lelé.
When thinking about the human side, from workers to end users of his buildings, Lelé brought bioclimatic issues to the center of his work. Thus, it has become a great reference in passive strategies - without spending on mechanical or electrical energy - for building comfort, presenting a mastery of fundamental techniques for the reduction of greenhouse gas emissions, along with the improvement of energy efficiency. Therefore, we analyze the architect's professional practice and divide it into three main points that help to think about architecture in a more sustainable way.
Less Waste and Better Use of Materials
Among the most used materials in buildings are concrete and steel. Despite their durability and resistance, they require high energy consumption and emit pollutants during their production processes, contributing to the emission of greenhouse gases. By adopting them, Lelé generated more efficient processes using industrialized techniques and the construction system itself. Therefore, it created an integrated project in which pre-fabrication allowed the reduction and use of waste, mitigating damage to the environment and bringing productivity gains.
For impeccable execution, the project had a defining role. With the architect performing his role as coordinator of the whole, the designs reached numerous details that solved all material issues leaving less room for possible errors and waste at the construction site. In addition, care was taken to design the prefabricated parts so that the assembly took place in the simplest and most effective way: with easy transport and also allowing them to be handled only by humans, and not machines, through their loadable sizes and weights. Therefore, there is a lower consumption of fuel or energy during construction.
Another fundamental factor is in Lelé's design vision, which did not see the project delivered as ready, but the life of the building in its future. In his architectural design, he envisaged some solutions to accompany the evolution of the building according to possible new demands or technological updates, so that it does not become obsolete and manages to transform or have easier maintenance according to what was built. Therefore, building versatility is created, avoiding unnecessary demolition and greater material expenditure.
Let the Wind In
When designing for a tropical, hot and humid climate, the wind plays a key role in cooling and making the building healthier for its users, so solutions such as air conditioning become expendable. Thus, Lelé thought of different mechanisms to allow cross ventilation in ambiences. In addition to the roofing, as will be seen later, there was a concern to keep the wind blowing through permanent openings or frames that allow air to enter when necessary.
The efficiency of this solution is even greater since there is a special concern with the façades. In many projects, Lelé creates a buffer area based on various responses: balconies with generous eaves, vegetation and water features. Spaces that make the air even cooler before it moves through the interior of the building and that, together with the internal gardens, collaborate with maintaining a milder temperature and humidity in the ambiences.
One of the best known projects is in the ventilation system created for Sarah Salvador hospital, in 1994. Here, Lelé designed an underground gallery, in which the air is supplied through metallic ducts that are inserted between the reinforced mortar partitions, then go to the wards through ventilated shutters and, later, it is extracted through the sheds that are oriented in the opposite direction of the prevailing winds - to create pressure and collaborate with the air extraction effect.
Roofing as a Thermal Balance Instrument
The solutions adopted by Lelé on the façades ensure that they do not have a significant thermal gain. Therefore, to crown the thermal comfort, it is essential to think about the roofs. Over the course of his life, Lelé increasingly developed this aspect in his work, increasing the height of buildings, creating air mattresses to increase thermal protection, adopting insulation between the aluminums and opting for light colors to increase reflection and absorb less heat.
Finally, it is worth mentioning the characteristic use of sheds that have become major protagonists, especially in Sarah network’s case. In some projects the composition of this element gains transparent materials, such as polycarbonate, and moving parts that can be opened or closed depending on the situation, thus, they allow natural ventilation and lighting enhancing the quality of the space.
The architect is being honored at an exhibition at Escola da Cidade. One of the curators, Valdemir Rosa, reminds us that "the exhibition is meant to show an architect who, in the 20th century, was already thinking about the 21st century". A statement that summarizes the importance of his work, which remains extremely actual and relevant to think about a future in which civil construction also makes a difference in the climate scenario. May Lelé keep inspiring the future.
This article is part of the ArchDaily Topics: The Road to Net Zero Architecture presented by Randers Tegl.
Randers Tegl aims to take responsibility and think sustainable as a part of reaching the goal of Net Zero. Both in terms of how building materials impact the climate and how the materials age, but also with a focus on architecture. That is why Randers Tegl created their sustainable series GREENER, which comes with full documentation in the form of EPD, so it is possible to use the product in technical calculation programs.
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