To be sustainable, a city requires using more than just environment-friendly materials and dedicated water-energy efficient systems. Truly sustainable urban systems are end-to-end solutions necessarily built upon design. Civil construction is somewhat emblematical. Determining whether new buildings are feasible and sustainable requires more in-depth reviews and not only assessing the appropriate use of electric energy, water, gas or basic sanitation services. Since 1999, the city of São Paulo has regulations that control waste collection from this industry. A few regulation bodies, such as the Green Building Council Brazil (GBC Brazil), which offers the LEED Certification, have set specifications that determine whether a project is green.
Architect Ana Simão thinks we should take a step further: aside from smarter buildings, a sustainable city should be the result of an integrated and all-inclusive design. “Using energy-efficient lighting and reclaimed water on new buildings is not enough, and the whole infrastructure should take a coordinated design approach that continually leverages waste as a way of saving energy,” she says.
Although public and private institutions have set guidelines based on environmental, housing, or commercial initiatives, many cities do not follow good densification practices. It is a common thing to see districts being developed and expanded following spontaneous trends. Heavily residential cities are now seen as mere “bedrooms” and require people to commute from long distances to their working or shopping places; this overloads urban transportation systems, be it by mass transportation or individual vehicles. “São Paulo grew up lot by lot, featuring only a few mixed zoning neighborhoods. Densification and urban structures should be conceived altogether,” points out Verônica Polzer, architect, researcher, professor at Mackenzie University, and solid waste management consultant.
Effective communication stands out as a key tool for structuring a sustainable city. Verônica mentions, for instance, gas and basic sanitation facilities: if carriers worked side by side with energy supply companies, drilling the asphalt for maintenance would be the right time to hide into the ground the wires that go through public utility poles carrying electric energy or internet signal to households. She thinks it is important to “join forces to solve problems. This is something really sustainable and groundbreaking.”
New designs, old technologies
The most efficient solutions are often found in simple, traditional practices, even when these require new applications or redesigns. This is the case of the natural, low waste generating, handcrafted adobe tile, which is manufactured at the very work site and needs to be protected against moisture. “This is a great thermal, acoustic material, much superior than the one we currently use in civil construction,” says Verônica.
A few green tile models are largely used already. Although a little bit more expensive, these models do not undergo that typical burning process and are adherent, i.e., they stick to each other without mortar. A single detail makes all the difference from a sustainable standpoint. Some brands provide center-holed tiles; this allows running pillars and beams through tiles and making work easier, as well as producing less debris at the end of the process.
And who doesn`t know the difference a tiny plant makes at home or at the office? Green walls have been introduced recently to help the city breathe better and are everywhere now. The São Paulo City Hall started supporting this practice in 2016 for streets and avenues by covering graffiti sprayed spots with vases sprouting leaves and flowers. However, Verônica draws our attention to the fact that such ordinary walls have not been designed to support the weight and moisture these plants add, so currently it is impossible to estimate how much damage they cause to the structure of walls. Besides requiring ongoing maintenance, green walls demand high implementation costs. “In this case, green roofs would be a better solution, as seen on Shopping Eldorado. If an infiltration occurs it can be easily fixed without compromising the structure,” she says.
Another innovative example of sustainable initiative is the use of containers. This is a groundbreaking solution in terms of cargo transport, but ground equipment has a varying lifespan of only 8 to 20 years. After this, it should be decommissioned and reconditioned in order for its material to be further reused in civil construction. “It is awesome. It is a user-friendly, clean, fast, and affordable solution for those looking for a house,” explains Verônica.
Although still seldom used in Brazil, many foreign initiatives have included the use of containers for wide open spaces. One can see this at the students village in Le Havre’s university town, France. Four-story buildings have been set up from old containers, giving rise to 100 apartments of 24 square meters per unity.
Co-design: thinking together
Since many cities have been disorderly and thoughtlessly built, an effort to drive sustainability should make people urban-aware and encourage social interactions aimed at meeting the needs of those who use both individual and mass spaces. That’s where co-design comes into play: a methodology for designing the city’s architecture with its population. Architect Vanessa Padiá worked over eight years as a coordinator in charge of developing an urbanization plan for the Heliópolis district, a neighborhood located in southern São Paulo. A technical team collected all ideas conceived by the community and translated them into a physical mock-up; this provided them with a better view of their work and leveraged conversations.
After reaching a common ground, they could identify bottlenecked paths, unhealthy infrastructures, possible new confined areas, and removals that would yield collective benefits. “Community leaders started sharing their thoughts, and showing which initiatives would have a positive impact,” tells us Vanessa. “We need to engage the whole community, so that the work done is positive and long-lasting,” she says.
She explains the sense of space and its usage may vary from audience to audience. An area disregarded by the project would be invaluable for users. “Maybe it is a place where kids fly kites or play marbles. Maybe it is the place where a lady deploys her beach chair for sunbathing. A kitchen might be of great importance for a family who uses it as a living room,” lists the architect. “Local residents are key when it comes to urbanizing communities,” she wraps up.
What would nature do?
Another helpful way of conceiving sustainable designs is biomimetic. Behind a hard word stands a simple solution: watching how plants and animals handle common challenges. It is about translating natural functions that would be embedded into projects based on their visible structure. Didn’t get it yet? A master in engineering and also a biomimetic consultant, Giane Cauzzi Brocco quotes the Japanese fast train as an example, whose noise was so loud that it could be heard 400 meters away. Because of air resistance, the train produced sound bursts when passing through tunnels. The solution was in the kingfisher’s beak - to catch its food, the small bird dives fast into the water while making virtually no noise or splashes at all. The secret is in its air resistance piercing beak design. Applying the same bird beak design to the train solved the problem.
In Brazil, GCP Arquitetura e Urbanismo built Votu Hotel at Algodões Beach, Maraú Peninsula, state of Bahia. The hotel was designed using the biomimetic approach. The project includes an auto-shading feature inspired in the effect produced by some species of cactus, besides a smart roofing for the building that uses natural air circulation and ensures thermal comfort based on the design of lairs made by prairie dogs, who drills dynamic air inlets and outlets at dug areas. The hotel’s kitchen works on a system that exchanges heat with the outside ambience, similar to the way toucans cool themselves through their beaks, while releasing the excess heat - the strategy keeps temperature stable and avoids spending money on air-conditioning systems.
Another example is the Eastgate Center building in Zimbabwe. Inspired on mounds built by termites (insects similar to white ants), this commercial complex does not use any artificial cooling or heating system. Air inlet and outlet channels use a smart system to open and close, while keeping room temperature at nice levels and reducing energy operating costs by 40%.
Giane concludes that a Smart City should not rely only on its household appliances or connectivity devices. “A Smart City lives by the same principles a rain forest does, which includes protecting living organisms, making coexistence possible, reusing natural resources, engaging people, promoting collaborative approaches, and embedding sustainable solutions,” she says.