Why green cities are important

September 6, 2019

Urbanisation is putting pressure on our planet's resources like never before. Between 2019 and 2025 over 2 billion square meters of new building stock will be developed every year! It is important to consider what impact these new structures will have on our planet and on the people that will inhabit them. We believe a return of timber as main construction material has many environmental benefits and could make cities a better place to live in.

The impact of the construction industry on our environment

Few people know that the construction sector is currently one of the most polluting sectors on earth. A study by Willmott Dixon (2010) indicates that the sector is responsible for 23% of air pollution, 50% of total climate change, 40% of drinking water pollution and 50% of all landfill waste. Especially the concrete and steel industry are big polluters. A different study by the U.S. Green Building Council (2016) reveals that buildings alone account for more than 40% of total energy consumption on earth.

In our last blog we discussed that cities are growing incredibly fast and by 2050 over 70% of the world population will live in an urban area. In other words, we will need to develop tons of new buildings in order to be able to welcome more than 2.5 billion new citizens in the coming decades. To keep the earth habitable we believe it is essential to consider the impact of buildings, as well as the consequences of our choices for material, design and manufacture for current and future generations.

One of the solutions could be to return to one of the most traditional building materials: timber. The potential of this material is huge, with benefits such as reduced energy consumption, reduced CO2 emission, and the ease of transportability as opposed to steel and concrete.

Benefits of building with cross-laminated timber

Timber is without doubt the most used construction material in human history, but in the last century concrete and steel have surpassed the use of timber. Nevertheless, the return of timber as main construction material could play a key role in reducing our carbon footprint. Timber has two main benefits compared to using concrete and steel:

  1. When trees grow they absorb carbon from the atmosphere. So when we use timber to construct buildings the CO2 is basically captured in the material, giving it a big advantage over concrete and steel.
  2. On top of that, timber is also much less carbon intensive to manufacture and transport compared to concrete and steel.

The past few years architects all over the world have started to use cross-laminated timber (CLT) in their designs. Compared with regular 'timber, cross-laminated timber provides additional strength, stability, durability and fire safety. These additional benefits make timber finally a viable option to use as main construction material in the development of large buildings and even high-rises.  A beautiful example is shown in the video below from architect Chris Precht.

The rise of green cities

In addition to the fact that urbanisation has a big impact on our environment, we also need to consider the impact of urbanisation on the people who live in our cities. For the past century, nature has disappeared from our streets. Apart from the fact that no one wants to live in a concrete bunker, we believe the presence of nature is a big contributor to the wellbeing of our citizens. It is proven that nature, planting and trees contribute significantly to social integration, reduced crime, improved physical and mental health.

“One of the most striking examples concerns Chicago’s Robert Taylor housing project, the largest public housing development in the world when completed in 1962. Of the 28 tower blocks, studies showed that those surrounded by trees and greenery were linked to 48% fewer property crimes and 56% fewer violent crimes compared to identical blocks surrounded by barren land. The green spaces were found to bring people together outdoors thereby increasing surveillance and discouraging crime, while also reducing aggression and helping people relax. The city planted 20,000 more trees as a result of the study.” (Arup, 2019, p33-34)

Unfortunately, nature has left our streets already a long time ago and with land becoming more scarce this issue will become even bigger. We believe we can bring nature back to our cities by starting to integrate it in our buildings. Green building have many benefits. A study by TRADA (2015) shows that individuals who live in green buildings participate more in social activities, have more visitors, know more about their neighbours and have stronger feelings of belonging. Even more interesting is that not only trees and plants have a positive impact on the way people feel, but also natural materials like wood can do the same. The use of timber inside and outside of buildings lead to more positive feelings, less stress, lower risk of depression, and improved health in the long term (Nyrud & Bringslimark, 2010).

At Habit, we are on a mission to rethink the way we build and bring nature back to our cities. We envisage buildings made out of timber integrated with a lot of green in which our residents feel a true sense of beloning.