In this final article in our five-part series examining sustainability issues in airport design and construction, we look at the factors that influence material choice and how the COVID-19 crisis has accelerated the debate.

The materials balancing act

Performance versus cost has always been at the heart of material choice. In recent years, sustainability has taken a more central role in the decision matrix. The options around sustainable materials will only increase as technology improves, costs change, and legislation catches up with innovation.

However, sustainability considerations alone cannot inform material choice. It’s easy to get bowled over by the environmental credentials of new resources such as the (unlikely?) use of mushrooms in building materials. But if their durability is not up to the levels of usage required, the costs and massive disruption to airport operations due to frequent replacement could cancel out any advantages. Materials chosen for reasons of cost, appearance or functionality can however turn out to be the most sustainable choice. In this case, sustainability improvements may be derived from the way the material is handled, sourced or repurposed rather than by changing the material itself.

As consultants, one of the things we must do is weigh up the relative benefits of one material over another and base our recommendations on this calculation. We must also be prepared, where appropriate, to challenge the norm and move away from the status quo of how things have always been done. That means being open to new technologies; viewing them objectively and avoiding seeking change for change’s sake.

Keeping it clean

Hygiene has always been essential in areas of high footfall such as airports, but COVID-19 has highlighted the massive impact that maintaining a safe environment can have on operations. This not only affects what things are made of but also how they are assembled.

COVID-19 has also highlighted an immediate need to consider how materials are disposed of –the mountains of face masks discarded each day being a case in point – or how items such as Perspex protective screens can be repurposed once the acute risk of infection has been assuaged. In the rush to provide safety equipment, the sustainability of such items was a low priority.

As important as hygiene is though, we cannot allow every public building to resemble or have the physical attributes of a hospital. So how do we balance hygiene requirements with ambience?

Getting it right from the start

Sustainability is not just about what new buildings are made of. Before we even start designing a new building, we must ask ourselves whether the building is actually needed. Could existing structures be reused for example? Or are there options to use available space more efficiently?

If a new building is deemed necessary, the potential for future repurposing, moving and adapting it is an essential factor in determining its long-term environmental impact. We have discussed previously that buildings need to be flexible to meet changing expectations<- interne link, but the role that material choice must play in this is sometimes overlooked.

Well selected materials can have a positive impact on user experiences. An attractive, pleasant space will not only contribute to improving the customer journey but also encourage people to use the building carefully, so reducing the need for repair or renovation – which in turn improves its sustainability.

Architects must also consider how trends and changes in usage or ownership might impact on the different layers of a building. The façade might need to be updated more frequently than the internal elements, so this too will have an influence on decisions around material choice.

This need to consider the long-term flexibility of buildings is another element in the increasingly complex decision matrix around materials. By ensuring the materials selected lend themselves to adaptation in the way they are assembled or used, the long-term future of the building is improved.

Additionally, we must factor in the potential for changes in legislation which might lead to buildings being retrofitted to meet health and safety standards for example. We’re seeing this now with the necessity to rearrange airport layouts to allow for social distancing and improved hygiene at touch points. So, it’s essential that we understand possible future risks and build flexibility into both design, material choice and assembly options to ensure we can more easily adapt to changing circumstances.

This mitigation of risk can have effects that are greater than the immediate impact on the operation of the building. For example, the use of green roofs, as in the case of Amsterdam Schiphol Airport, can act as a stormwater buffer and thus reduce stress on municipal drainage by slowing the release of rainwater into the wastewater system.

Innovation driving legislation

Sometimes, there is a need to make decisions based on meeting specific legislative requirements. In the rapidly changing world of materials, it is innovation that is forcing the pace of adoption, with airports ideally placed to be driving this.

We’ve discussed in the past that airports can be seen as ambassadors<-interne link; operating as they do as small cities in many ways, with all the associated infrastructure. They are often also the gateway to a country and as such, responsible for the first impressions given to new arrivals.

In developing countries where the established building infrastructure is under developed, the opportunity to set the tone in terms of material choice and sustainability<- video/link is private from the start is one that should be enthusiastically embraced. Selection of locally manufactured materials –where appropriate– would further support sustainability goals through reduced transport costs and would also bolster the local economy.

By recognising the important role that they must play here, airports can be ahead of the curve in terms of public opinion as well as cultural and legislative change.

Finding the silver lining

The need to balance sustainability with practicality and cost will always lie at the centre of the debate around material use. COVID-19 has led to a lowering of standards when it comes to sustainable material choices as the immediate need to address hygiene concerns has in part overtaken environmental considerations.

To avoid this in the future, material choice must be made with long-term risk and flexibility in mind. There’s no avoiding the fact that COVID-19 has done lasting damage, but if we can use it as a catalyst to drive forward longer-term goals in material choice and building design, this at least is a silver lining which suggests that now really is the right time to talk about and even rethink material use.