Heat islands, biophilia + the need to be green
Nature has always played an essential role in human imagination and expression of the built environment. However, in 2022, greening our buildings and cities will have new meaning and purpose. For too long we have believed in unlimited natural resources and unlimited habitats, and have only recently begun to understand that the world and nature have limits. A rapid transition from a human-centred to a nature-centred understanding must occur to prevent further damage to the planet and the environment.
Without a significant immediate reduction in emissions across all sectors, it will be impossible to limit global warming to a maximum of 1.5°C, after which it will be irreversible. We must reduce, if not prevent, all new carbon dioxide2 Emissions from building construction and operation, as well as finding ways to extract and store carbon already in the atmosphere. Trees and plants are vital to preventing global warming because they can sequester carbon from the atmosphere. The evaporative cooling and shading effect helps prevent urban heat island effects.
The urban heat island effect refers to the difference in temperature between a city and neighboring less developed areas. However, they can also appear within a city context where large non-vegetated areas are adjacent to a shaded, cooler urban fabric.
Cities such as London, Dubai, Singapore and Los Angeles are prime examples. Here, hotter and drier summers resulting from global warming are amplified by heat island effects. Some reports indicate that these cities can be up to 10 degrees warmer than surrounding rural areas. A warmer climate can present problems for older adults or those with health conditions.
To combat this, we need to envision a built environment that promotes ecological balance (sustainability) and, more importantly, a restorative approach that returns to the land what was taken from it (regeneration).
Bringing plants into our buildings and cities isn’t just about sequestering carbon. They have a positive impact on our health and well-being. A study conducted by epidemiologist Dr. Payam Dadvand (Centre for Research and Environmental Epidemiology of Barcelona) in 2015 showed how green spaces directly affect the cognitive development of primary school children. Illustrating how each increase in landscape in the environment over the course of one year results in a five percent short-term improvement or development of working memory. The city’s landscape also encourages active travel and physical exercise.
Lessons from London
London is a leading example of greening, with more than eight million trees and 3,000 parks. Reports indicate that trees cover 21% of the city’s area. The recent trend of urban rewilding promotes biodiversity, clean air, physical and mental well-being, and active travel. Creating rainwater gardens, butterfly trails, and reusing brown sites and existing structures are all focused on renewal and restoration.
While many steps point in the right direction, more needs to be done on the ground beneath the tree canopies. Asphalt or paved areas can represent 50% or more of the total city area. Concrete and petroleum-based asphalt have a large carbon footprint. Recently, in development are CO2– Reduced alternatives such as carbon dioxide2– Reduced concrete, Greenbloc or a warm alternative to asphalt.
London’s squares, streets, rooftops and large urban infrastructure remain heat islands. Perhaps the most famous example of this in London is Trafalgar Square, a mass of gray concrete and amphitheater surrounded by busy roads with little green space. However, it was very encouraging to see it transformed in April this year into a day with Green Blanket to help raise awareness of rewilding.
A more recent example is the King’s Cross redevelopment area opposite Google. Although it is often celebrated as a great example of placemaking and regeneration, its uniform composition does little to address these concerns, with artificial turf on its steps, which although green, brings no benefit.
This issue is widely recognized. “Through planning policy, we are managing heat risks in new developments as well as increasing the amount of green space and vegetation to play a role in cooling the city,” the London Assembly notes. In line with this, we see tangible, positive transformations in urban design across London. We should ultimately consider ourselves fortunate to have so many well-maintained parks and gardens and ever-increasing green initiatives.
One important example is Canary Wharf, a dense, historically gray area of London undergoing significant green improvement. Today, it offers about 20 acres of landscaped parks, gardens and plazas and 70,000 new seasonal plantings annually. The recent arrival of the Crossrail Place Roof Garden, one of London’s most important parks, once again underscores this commitment to greening, providing tranquil spaces for residents and visitors, and helping to reduce the heat island effect. Paddington is another excellent example, home to its extensive green wall, canals and a collaborative strategy from various landowners to create positive change.
The London Energy Transformation Initiative (LETI) sets out measures to help transform London’s built environment to net zero carbon. Urban Greening Factor (UGF) is another tool used to evaluate the quality and quantity of urban greening. It enables and encourages key developments from the beginning of the planning process to determine how much urban greening will be incorporated as a key element into the site and building design and how it will meet the London G5 Urban Greening Plan policy.
Green spaces can act as a carbon store, offsetting some of the carbon buildup in urban areas with heavily enclosed surfaces such as sidewalks and buildings. Plants benefit human health through their ability to reduce noise pollution and remove pollutants, including ozone. This has a direct impact on improving the health of urban residents. According to some studies, just one square meter of green roof offsets a car’s annual particulate emissions.
Green is good for the environment, creates added value and improves the quality of life and neighbourhood. Greening strategies positively impact highways, communities and productivity while increasing the value of businesses and real estate.
Another popular aspect is the so-called urban agriculture or rooftop farming. Urban agriculture has a positive impact on the social and emotional well-being of individuals, communities and the environment. There is plenty of unused roof space in London and in cities around the world to use for agriculture. Locally grown food can help reduce energy consumption in transportation.
This renewed focus on urban green spaces leads to the concept of biophilia, which is defined as “the innate human instinct to connect with nature and other living organisms.” From an architectural perspective, the principle of biophilic design is about connecting people to nature, bringing elements of our natural world into the built environment, such as natural light, water, plants, and natural materials such as wood, stone, and texture. Of textures, patterns and shades.
Biophilic design doesn’t have to be complicated and expensive. Ultimately, it’s pretty straightforward; We need to provide nature with the open space it needs to live and thrive. Trees and plants are wonders of structural performance, functionality, and carbon sequestration. Maybe buildings could become like trees.
Looking at interior design, we know that retail and shopping environments, for example, are a highly emotional experience, and that the look and feel of a store has a tangible impact. Incorporating biophilia, which brings natural comfort, into the design can create a premium destination where people want to stay for long periods. Designing spaces to include water features, trees, and semi-temperate, open landscaped areas can create an environment that provides the psychologically calming effects of nature and has been proven to attract people and extend dwell time.
By designing climate positive and sustainable buildings that amplify the connection to nature, we can make a significant difference in our cities.
(tags for translation) Biophilia