Nature: the engineer's missing tool.


Robert Winch, Senior Consultant

Protecting and restoring biodiversity.

Additional Authors include Ashley Bateson, Director and Chin Chen, Senior Associate at Grant Associates.

This article was first published for CIBSE.

A biodiversity emergency

We are in both a climate and biodiversity emergency, two interlinked crises with local and global impacts being felt today. Increasingly, reducing dependency on fossil fuels has become a key priority for businesses, governments and people across the world. A catalyst for this was the 2015 Paris Agreement, adopted by over 190 countries, which set a clear and shared goal of pursuing efforts to limit global warming to 1.5oC.

Many consultants in the built environment have signed up to the international declaration of the climate and biodiversity emergency, including engineers, architects, project managers and landscape architects (1). In the UK alone, over 120 companies have joined the Building Services Engineers Climate and Biodiversity Emergency Declaration (2).

This declaration entails a commitment to collaborate, share knowledge and advocate increased resource efficiency on projects and more regenerative design principles.
The importance of biodiversity has not received the same spotlight as decarbonisation, but there is a sense we are on the cusp of change. At Davos 2020 a new global ambition was born, “nature positive by 2030”, this is viewed as the biodiversity equivalent of the Paris Climate agreement.

A driving force behind this shift in focus is nature’s unprecedented free fall, which has meant that since 1970 the relative abundance of monitored wildlife populations has declined by 69%, this figure was 60% five years ago (3).
The need for designers to be more aware of the role of protecting and incorporating nature in building development was also recognised at a recent annual conference of the UK Building Services Engineers Climate and Biodiversity Emergency (4).

The need to protect and restore biodiversity

At the most basic end of reasoning nature must be protected and restored because it is fundamental to our survival. Our natural world provides the clean air, food and water we need to thrive alongside improving our wellbeing and reducing threats of zoonotic diseases, even more prevalent following the effects of COVID-19.

Nature’s services to us, otherwise known as ecosystem services, are near infinite including everything from climate regulation, pollution reduction, medicinal plants, construction materials and eco-tourism.

For the UK’s built environment sector, a radical transformation is beginning to revalue nature. This is in part spurred by new national regulations that from November 2023 all new developments will be required to create a 10% biodiversity net gain, something many Local Authorities are already requiring be exceeded. This legal mandate is encouraging developers and asset owners to seek out the multifunctional benefits associated with nature. Beyond planning requirements, as of May 2023, organisations can set Science-Based Targets for Nature, similar to their carbon equivalent, this approach will give companies a clear structure to protect and restore nature in line with science.


Green infrastructure

Nature-based solutions provide green infrastructure like green walls, biodiverse roofs, gardens, parks, and Sustainable Urban Drainage Systems (SuDS) which have social, economic and environmental benefits. To date, engineers haven’t fully embraced nature into their toolbox but if used at scale, they offer a means of reducing the risk of the climate and biodiversity emergency.

As a building solution they not only have a low, or in some cases negative, embodied carbon impact but over their lifetime but actively pull carbon out of the atmosphere. Furthermore, focusing on nature-based solutions naturally results in an uplift to site biodiversity.

Modern developments typically target a wide spectrum of outcomes to ensure they deliver against various stakeholder expectations. Nature-based solutions, due to their diverse range of benefits, are becoming an increasingly more cost-effective solution to deliver on these priorities

Green roofs are one type of nature-based solution which are becoming increasingly common, particularly in cities and towns with a scarcity of space. 1 New Street Square, CABI Office and Greenwich University Library are examples of developments which have embraced green roofs as part of their design. In addition to their basic function of providing shelter these roofs are outcompeting their traditional alternatives by improving building performance and occupant experience. One of the more significant benefits of a green roof is its ability to alleviate some of the Urban Heat Island affect by shading the heat storing hard surfaces and absorbing solar radiation through evaporation and evapotranspiration. Consequently, reducing both internal and external air temperature by 4oC and 1oC respectively (on average). Green roofs can also, on average, reduce noise by 11db, increase property value by 6.9% and store 73% of rainwater runoff.

Quantifying nature’s value

Nature’s economic, environmental, and social value has historically been hard to quantify but at the same time evident to see and experience. For this reason, nature has struggled to be fully utilised in building design.

The Earls Court Development project, an ambitious redevelopment of the long neglected 40-acre site in Zone 1 London, has been a test bed to develop an approach to quantifying the value of a landscape-led development. For this, Biome has been created which uses data from a meta-study of scientific papers to build a value profile for each nature-based solution type. These profiles enable landscape strategies to be appraised considering how they contribute to the attainment of the development’s sustainability targets, business priorities and wider value creation. The outcome being the ability to influence and support decisions around landscaping design based on the desired attributes being sought.

As an example, take a typical masterplan containing a busy high street with lots of pedestrians and road noise. Prioritise might include reducing the risk of pedestrians overheating in the summer, decreasing the noise pollution experienced building occupants, and avoiding flood risk. Biome could be used to identify the mix of nature-based solutions to optimise delivering against these prioritise. For instance, Biome would identify that the trees on average reduce air temperature by 3oC, can absorb 4db of sound and reduce rain rainwater runoff by 43%. Some unintended benefits would also include that trees can contribute to net zero targets by sequestering carbon and help attract new retail tenants by increasing people’s willingness to spend in local businesses by 30%.

Nature-based solutions can also return financial value, last year UKGBC released guidance on The Value of Urban Nature-Based Solutions, this report outlines how nature-based solutions can be the basis for financial benefits and new revenue streams.

Nature-based solutions can be viewed by engineers as an extension to their toolbox of approaches. In practice that will likely mean creating new cross discipline working partnerships. Tapping into the expertise of landscape architects, ecologists, and sustainability consultants to apply solutions to real world projects.