As part of World Environment Day, we interviewed the architect Bárbara Miranda to talk to us about sustainable architecture.

Bárbara Miranda, Portuguese, is an architect from the Faculty of Architecture of the University of Porto.

She is currently completing a postgraduate degree in Sustainable Architecture at Kunstuniversität Linz and is an intern at Studio Anna Heringer, Germany. She sees architecture as a powerful tool to change the world. She advocates sustainable, fair and responsible social, economic and ecological architecture. We have the architect Bárbara Miranda in this interview about sustainable architecture where we challenged her to develop the topic.

1. Bárbara works with the issue of sustainability in architecture. Can you tell us a little about this topic?

Sustainable architecture is, above all, a way of building without disrespecting the environment, architectural tradition, local communities and the economy. It is a very necessary topic these days, as buildings are responsible for 40% of energy consumption in the European Union. They produce 36% of the greenhouse gases emitted. It is urgent to debate, develop and practice an architecture that is as least harmful as possible for everyone.

2. Is the architecture practiced nowadays sustainable?

The architecture most commonly practiced today is based on materials such as concrete, brick masonry, cement or various types of metals. The big problem with these materials is, at first, the abusive use of raw materials such as water or sand for their manufacture, which ends up destroying the ecosystems from which they are extracted.

Then the problem goes through production. To manufacture these materials a very high energy expenditure is necessary, which consequently leads to high emissions of carbon dioxide into the atmosphere. Furthermore, due to the standardization of construction materials that are manufactured centrally in the respective factories, the transport of these materials is also responsible for numerous CO2 emissions.

Finally, it is also important to realize that the long-lasting “quality” of these materials ends up being harmful at an environmental level, since their degradation is very slow and destroys the environment in which they are inserted. On the other hand, sustainable architecture, as it is based on local and natural building materials and techniques, allows for less transport, less energy expended and less impact on ecosystems. Therefore, when we look at traditional Portuguese architecture, made of dirt, wood, fibers or stone, we can see that sustainable architecture is not, after all, a new concept, but a concept that is very present in our history.

3. What are the sustainability indicators in a project? Do they refer to materials and/or processes?

Sustainability in a project can be applied to all parts of the project. Measures such as: employing local artisans, remunerating workers fairly, using natural materials or respecting the traditional typologies of a given area are equally sustainable. At an environmental level, both materials and processes can be indicators of sustainability. Materials that are abundantly available in the construction zone, such as dirt, wood, fibers or stone, as well as construction techniques that favor human labor rather than the use of machines, make a project more sustainable.

In a more technological aspect, it is also possible to increase the sustainability index of a building by integrating the use of renewable energies in the building. But to be sustainable, the use of technology is not mandatory. For example, dirt buildings, due to their thermal inertia, can drastically reduce the need for technological devices such as air conditioners or heaters.

4. Do you consider that the use of the resource, natural stone, in architecture can go hand in hand with sustainability?

No doubt. However, this answer will always depend on the context where it is applied. In Portugal, we can witness the great presence of stone masonry such as granite or schist in architecture, especially in the north. This demonstrates the good use of an abundant element in this area in favor of architecture. In the south of the country, we can also see the importance of stone in Portuguese architecture through the extensive use of lime. Lime, from limestone, allows the walls on which it is applied to be breathable, has antibacterial properties and also helps in the reflection of the sun’s rays, which prevents the interior areas from overheating.

On a more general level, stone also brings immense constructive advantages when it comes to foundations or structural systems. All these ways of using stone demonstrate that to make sustainable architecture, we just have to look at the materials that surround us and use them in a way that has the least environmental impact and the greatest possible social and economic impact.
However, since stone is a non-renewable resource in this sense, its use must be considered.

5. In your opinion, are architects, engineers, construction companies, material suppliers aware of the need to preserve the environment and resources?

I would say that the younger professional generations are the ones that are most aware of the impact of architecture on the environment. However, there is still a long way to go to make architecture more sustainable. It is mainly up to developed countries to recover the traditional construction techniques that by themselves already respond to climatic, ecological and social problems and transform them into contemporary architecture that responds to the current problems of the 21st century. It is experts like Anna Heringer or Martin Rauch that we should be inspired to create healthy buildings for a healthier planet too.

We are grateful for the participation of the architect Bárbara Miranda in this Sustainable Architecture interview.