Lyons O'Neill

Building climate resilience into our built environment

In Europe, this summer is a sign of times to come. While countries in the Global South have been visibly, disproportionately experiencing the impact of climate change for years, nations like the UK have historically felt its effects far less acutely.

But times are changing.  July was the hottest month on record and Europe continues to struggle with intense heatwaves, storms and wildfires. Last summer, over 61,000 people died in Europe as a result of the heat.

With greenhouse gas emissions at an all-time high and global temperatures continuing to climb, new climates are being created. Recent research has found that the number of days of uncomfortably hot temperatures will increase by almost a third in the UK and Switzerland, if global temperatures rise by 2⁰C.

Current infrastructure is simply not built for this new burning world. It’s more than a lack of integrated air con: buildings in northern Europe are often designed to trap heat for winter and so become untenable in high temperatures. Steel train lines buckleRoads melt. Then there’s the other effects of climate change. Violent storms, flooding, more frequent weather extremes.

Designing for a new climate

As our climate changes around us, architects and engineers have two duties. The first is to make sustainability the top priority for every project – so there’s an inhabitable planet to build on in the future. The second is to design infrastructure and buildings that can protect people and continue to function under these new conditions.

Often, the two go hand in hand. For instance, rainwater collection and grey-water reuse systems reduce a household’s draw on regional water supplies, whilst serving inhabitants in seasons of drought. ‘Blue roofs’ and ‘green roofs’ are also features that help manage water flow in this new climate – acting to control drainage during periods of heavy rainfall.

Such new adaptations are outlined in the World Green Building Council’s industry guide on Climate Change Resilience in the Built Environment, released last October. The guide lists a number of measures designers can take to combat extreme heat including adding semi-permanent shading devices, opting for light-coloured roofs and carefully choosing building orientation and areas of glazing. Designs such as patio and atrium designs additionally allow natural ventilation and cooling and ‘green roofs’ (partially or fully covered by vegetation) act as passive cooling techniques. Even a change as simple as external shutters, commonly used in countries beyond the UK, can greatly mitigate heat. The use of thermal mass can also assist with cooling but this should not come at the price of overall sustainability: concrete has both a high thermal mass and environmental cost.

Greater climate resilience is quickly becoming a legal imperative, as well as a moral one. Governments are waking up to the need for greater climate resilience with the UK issuing updated planning guidance last August, to better protect new homes from flooding and support local areas with sustainable drainage.

Resilience in action

But the construction industry shouldn’t wait for regulatory pressure to build climate resilience – by then it could be too late. It’s time to start incorporating resilience techniques into projects so the work we do now can last.

For example, our recent project at Penarth Street, Southwark, saw us work on a housing development and install blue roofs to help with surface water harvesting. These roofs will limit the discharge from the site and subsequently reduce stress on the local sewer infrastructure, which is set to face huge strain with the increasing frequency of heavy rainfall and storm events.

We’re facing a changing environment – the challenge now is how to adapt to it.