Architects need to consider different scenarios for what the climate will look like in 50 years when they design buildings, according to a report by the British Council for Offices (BCO)
The study argues that developers and designers need to ‘de-risk’ buildings by reducing the effects of worse flash flooding, gales and heatwaves than the UK is currently used to.
‘It would shock the general public to understand that buildings are designed based on the average weather over the past 20 years, not taking into account what is happening now, let alone in the future,’ said Simon Wyatt, lead author of the report and sustainability partner at consultant Cundall.
‘We need to look at how we are designing buildings which are fit for purpose in 20, 50 or 100 years. Everything from architecture, building services, wind load, ground movement and material expansion, heating and cooling loads – all these things are affected by weather, but none of them are [currently] based on climate science,’ he added.
Developers should therefore consider what ‘climate scenario’ they are designing to – an increase in the average world temperature of one, two, three or 4°C.
Wyatt pointed out that a global temperature change of 2°C is more significant than it sounds, as sea temperatures would increase by around 1°C while land temperatures would experience an increase more like 4°C.
And even the latter temperature is an average, so the peak summer temperature in a city like London could increase by around 10°C. Climate change could also see the amount of rain dropped during heavy storms increase by 200 per cent in some areas, according to Wyatt.
Developers should, the BCO report suggests, therefore take a risk-based approach: if designing for a worse scenario costs little, then it will be worth doing, whereas if its costs lots it may be easier to mitigate the worst case through insurance or other methods.
‘Architects need to understand the impact of different scenarios for design,’ says Wyatt. ‘For example, if a client wants a naturally ventilated building, what are the opening areas on a glazed building for the 3°C and 4°C scenario? Architects need to be able to explain the difference to clients.’
The report notes that developers are increasingly being asked by insurers and investors about what they are doing to make sure buildings are able to adapt to, and thrive in, a changing climate.
But Wyatt adds: ‘The problem is that there is nothing at the bottom of the industry telling people how to design for climate change.
‘What we are looking to do is work with professional bodies [such as CIBSE and RIBA] to review what design criteria are weather-related and see if it takes climate science into account.’