Kinley’s Sol Russel assesses the importance of utilising sustainable urban design solutions – to mitigate the urban heat island effect, improve air quality, and create more liveable urban environments.
While sustainability is rapidly becoming a major consideration of building design and efforts to decarbonise the UK’s building stock are proceeding with varying degrees of success, substantial population growth is adding a significant challenge.
In fact, the UK’s second largest annual numerical increase – rising by 755,300 to an estimated 69.3 million people in the year to mid-2024, is leading to considerable urbanisation up and down the nation. The associated increase in vehicles, industrial activity and energy consumption is seeing heightened air, water and waste pollution in addition to the urban heat island effect.
With the expansion of cities putting pressure on rural-urban fringes, reducing the amount of green space and risking air quality falling below World Health Organisation (WHO) guidelines, the importance of creating more liveable urban environments through effective landscape design cannot be understated.
Improving air quality & wellbeing
Despite long-term reductions in particulate matter, such as PM2.5 and PM10, and nitrogen dioxide levels, many urban areas – Manchester, London and Birmingham for instance – still exceed WHO guidelines for air quality according to reports.
To that end, taking a biophilic approach to landscape architecture design can have substantial impacts on air quality. For example, the strategic planting and delineation of vegetation can act as a ‘green screen’ between pollution sources, such as busy roads, and people.
Additionally, with trees and other plants acting as filters, they are able to trap particulate matter from the air while absorbing pollutants and carbon dioxide from the atmosphere.
This will also have long-lasting influences on the urban heat island effect, with carefully considered trees and vegetation providing shade and maximising green space to cool nearby surfaces and lower local building air conditioning costs by as much as 50%.
Enhancing biodiversity & habitat creation
In developed or urban areas, using landscape design, such as landscape edging, can create vital wildlife corridors, enabling the easy movement of species and the spread of genetic diversity. Indeed, edging can be incorporated into the design to link up existing green spaces, woodlands or hedgerows to create a network of interconnected habitats.
With landscape edging acting as effective buffer zones, it offers substantial protection for more intensive habitats from wind, fire, pesticide spray drift and even human disturbance.
The specification and incorporation of sustainable materials in landscape design also play a vital role in enhancing an urban space’s environmental performance. In addition to mitigating issues such as the urban heat effect, sustainable materials, such as aluminium landscape edging, are manufactured with less toxicity and require less energy to produce.
Regulating local temperatures
By defining boundaries of different landscape elements, landscape design can play a significant role in contributing to temperature regulation. For instance, aluminium landscape edging helps maintain defined areas for features such as trees and water, which are the main drivers of cooling through shading and evapotranspiration.
Furthermore, the delineation of green spaces through the use of landscape design helps maintain the intended integrity and shape of these areas. Preventing fragmentation in this way ensures green spaces remain compact and provide more reliable and consistent cooling effects.
Architects and landscape designers must also consider the benefits of strategic placement of vegetation and garden boundaries. By arranging plants and other vegetation in wind corridors, convection efficiency can be optimised – helping to dissipate heat more effectively.
Encouraging a greater sense of community
With the UK’s population growth seeing cultural and social needs ever evolving, landscape design requires a holistic, forward-thinking approach that not only integrates biophilic needs but also focuses heavily on community.
Through multi-functional design, urban spaces can offer the flexibility to cater for a wide range of activities, be it recreational or community events, through to urban agriculture, ensuring they remain popular and well used by local communities in the months and years ahead.
Furthermore, designing spaces with wide and accessible paths and incorporating diverse seating options means these green spaces are safe and accessible to every member of the community.
Doing so will encourage a sense of pride and ownership in the local community and inspire residents and visitors to undertake regular care and maintenance to ensure these spaces remain aesthetically beautiful, biodiverse and beloved for many years.
The effective use of landscape design, such as beautifully designed landscape edging, was on display in a recent project at London Wall.
Together with the carefully selected plants, the specified folded top edge and corten finish of raised planter beds added contrast and composition to the landscape design and created an inviting and memorable environment where people could go to relax.
With average UK temperatures having risen significantly in recent years and urban development gathering momentum, utilising green spaces to reduce the urban heat effect and provide relaxing, cooling and inviting environments is set to take greater precedence in the coming months and years.
Landscape design will play a prominent role, emphasising the importance of working with experienced and specialised landscape edging and furniture manufacturers.
Sol Russel is specification team leader at Kinley