Authors | Jaime Ramos, Raquel C. Pico
New environmental requirements have led to a transition affecting architecture at all levels. The aim is to adopt ecological urbanism practices through the established trend of sustainable architecture. But what are the requirements for an architectural project to be considered sustainable?
The origins of sustainable architecture
It was in the 1960s and 1970s that people began to talk about sustainable architecture, a concept that became established in the vocabulary of design and urban planning in the 1990s and has remained ever since. The climate emergency has made it even more relevant.
In order to understand the meaning of sustainable architecture, we must first establish the impact of buildings in terms of resource consumption, long-term effects on ecosystems, waste generation or the creation of harmful gases. According to the International Energy Agency (IEA), buildings and the construction sector combined are responsible for over one-third of global final energy consumption. And they account for 40% of total direct and indirect CO2 emissions each year.
This is a key agent in relation to greenhouse emissions and global warming. Unfortunately, according to the IEA, there are no short-term solutions. The problem is that energy efficiency policies are too slow when it comes to contributing to urban sustainability.
These types of strategies reached 35% of buildings in 2018, but the margin of improvement barely reaches one percent each year. Increases in energy demand are largely to blame, particularly in extensive areas experiencing rapid growth in industry and technology, such as China or India.
The latest Global Status Report for Buildings and Construction, published by the United Nations Environment Programme (UNEP), emphasized in 2024 the importance of making this shift toward sustainable construction and acting on the existing housing stock. Investment in building decarbonization had increased by 14%. Concerns in the United States and Europe over energy instability had driven more sustainable upgrade actions for buildings in those regions.
“There is no credible pathway to address climate change without a radical transformation of the building and construction sector,” said Inger Andersen, Executive Director of UNEP, at the time. She also provided a valuable insight: “Half of the buildings that will exist in 2050 have not yet been built. This represents a major opportunity for the sector to reimagine the buildings of the future.”
What is sustainable architecture?
In this regard, the aim of sustainable architecture involves neutralizing the harmful effects of the sector that threaten the planet’s environmental stability and the quality of life of those living in the buildings.
By prioritizing sustainable building materials, green design strategies, and circular economy principles in construction, eco-friendly architecture enables the creation of buildings with a lower environmental impact. However, sustainable architecture is not limited to the construction process alone; it considers these spaces as a whole to ensure efficiency is maintained throughout their entire lifespan. The goal is to create long lasting spaces where people can live well and that are healthy for both the planet and its inhabitants. This is why energy consumption is carefully considered, passive or zero energy buildings are prioritized, and green areas are incorporated.
All of this is connected to the broader concept of sustainability and its different dimensions: environmental, social, economic, and public policy sustainability.
Principles of sustainable architecture
The primary areas of focus of sustainable architecture are cooling, ventilation, heating and lighting systems, water consumption and supplying power for other fixtures and appliances.
Ecological architects have various alternatives for finding efficient solutions in these areas and improving resource management. These can be grouped into three main categories.
Energy efficiency
Energy efficiency, in turn, can be split into two sub-categories. The first refers to the supply of renewable energy. This aspect still has a long way to go. Renewable energy met less than 14% of total energy demand in buildings in 2017.
To tackle this, more architects are integrating the deployment of solar photovoltaic systems on rooftops and facade cladding, the supply of wind energy, solar-assisted water heaters and heat pumps into their projects. In some climates, relatively modern options such as aerothermal systems can also provide great energy savings, although the initial investment is significant.
The second and crucial point regarding energy efficiency refers to the use of existing resources. This concept requires detailed planning in the initial phases of building designs.
A good example of this is in the area of lighting. Experts estimate that 70% of the lighting needs can be obtained from the sun. However, this rate is barely 25% in ordinary buildings today. It is important to note that lighting accounts for 17% of global electricity consumption.
Sustainable building materials
The use of appropriate building materials contributes and forms a fundamental part of the energy utilization seen in the preceding point.
But apart from this, the use of sustainable materials is becoming essential. They can be obtained from and adapted to the natural environment of origin, such as bamboo or wood, or they can be recycled products.
This concept is now seen as one of the pillars of sustainability and includes materials such as wood and all types of plastics. It is also worth noting that steel is 100% recyclable. In relation to all of the above, the homologation of unified criteria regarding the sustainability of materials is a challenge yet to be overcome.
In economic terms, this is a major and fundamental market. In the United Kingdom, 420 million tons of building materials are used each year.
Planning for smart space utilization
A building is not an isolated entity, but rather it relates and is integrated into a specific context. Therefore, the design and functions of the building adapt to the circumstances of the area in which it is located.
This in turn requires the implementation of urban planning strategies with specific sustainability criteria. This is one of the ideas of the aforementioned strategies and policies.
Mixed-use developments are designed to lower the environmental impact of buildings with a very simple concept: bringing together several architectural solutions in one building. This reduces travel and increases energy efficiency.
What is sustainable architecture design?
Ecological design seeks to control the all-too familiar impact of our homes, work centers, schools or leisure centers. Therefore, designs in sustainable architecture are inspired by the above principles and they do so, not just to be reflected in the end result, but also through the implementation of processes, starting with planning. Essentially, the idea is to design and create buildings that consume less energy, use more advanced sustainable solutions and develop specific social cohesion functions. Sustainable examples are able to address all of these areas and create a positive impact on multiple levels.
Examples of sustainable architecture solutions
The Green Roofs of Copenhagen
It seems logical to highlight what is known as the greenest city in the world as fine example of sustainability.
Before receiving the accolade, the Danish capital installed over 200,000 square meters of green roof gardens since 2010. These are roofs that not only enhance the city or reduce its carbon footprint, but they are also capable of capturing up to 80% of rainfall with the aim of storing record amounts of water.
Transparent wood
There are solutions with great potential, aimed at reducing energy costs in buildings, through the use of existing or newly-created materials. This is the case of transparent wood.
Developed by the KTH Royal Institute of Technology in Stockholm, 100 grams of this material (a mixture of lignin and acrylics), absorb 8,000 Jules of heat in two hours. Used in construction, it absorbs heat to then release it.
3D-printed buildings?
Although it sounds more like a sci-fi movie, the truth is that 3D printing in construction is now an emerging industry. Authorities in countries like Dubai estimate that by 2030, 25% of new buildings will be constructed using this technique. There are already practical examples, such as The Wave House, that demonstrate its potential uses.
3D printing architecture is providing some outstanding benefits for urban planning, particularly in terms of reducing costs and universal access to housing. It will also contribute to the use of more sustainable materials.
Buildings that provide added solutions
There have been some extraordinary examples of sustainable architecture projects submitted in sector-specific contests in recent years. There is a common denominator in the buildings at the top of the list: construction projects must offer added value as a solution to specific urban sustainability challenges.
That is the aim of the Methanescraper or Airscraper skyscrapers, finalists in the 2019 Skyscraper Competition and which could transform waste into energy or clean the air of harmful airborne particles.
In short, sustainable architecture is no longer a project for the future, but rather a present day requirement. This has been confirmed by the IEA statistics: in 2019 public energy efficiency solutions in the construction sector represented 40% of the overall investment.
Frequently asked questions about sustainable architecture
What do we mean by sustainable architecture?
Sustainable architecture approaches green buildings in a holistic way to reduce the environmental impact of construction. This involves working with sustainable design principles, applying the circular economy to construction, and using sustainable materials. The ultimate goal is to achieve zero impact buildings.
What are the benefits of incorporating green criteria?
In addition to reducing the carbon footprint of the construction process itself, it also leads to significant savings for occupants, for example through zero energy or passive buildings, and improves their quality of life, since greener climate control systems are also more comfortable to live with.
Is sustainable architecture a modern concept?
Although green building design has gained momentum in recent decades, architecture is learning from the past and, in particular, from traditional construction methods, drawing important lessons on sustainable design principles and eco-friendly techniques.
How much do sustainable building materials help reduce the carbon footprint?
Concrete and steel are among the most polluting materials widely used in architecture over the past centuries. Replacing them with alternatives such as wood can significantly reduce the environmental impact.
Is eco-friendly architecture a solution to the challenges of the 21st century?
It is undoubtedly one of the key factors in achieving more efficient urban development and improving quality of life for citizens. Sustainable architecture addresses fundamental challenges such as energy use, the durability of materials and buildings, and housing needs.
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