A report has claimed the 'silent killer' heatwaves could claim up to 10,000 lives annually in the UK without concerted action.

The Environmental Audit Committee has raised concerns over the UK’s lack of preparedness in its report on ‘Heat resilience and sustainable cooling’.

The committee of UK Parliamentarians heard that suicide risk is twice as high in the UK when the temperature was 32°C rather than 22°C.

"Work-related injuries also increase, and interrupted sleep patterns due to high temperatures can cost the UK economy £60bn a year, or 1.5% to 2% of GDP," the Committee said in its report.

The social and economic case for accelerating heat adaptation measures in the UK is clear-cut, and EAC recommends measures around prioritising passive cooling – that do not involve expending energy – and clear Government messaging on the risks of heat events, underpinned by a national strategy on heat resilience.

Nature-based solutions

Nature-based solutions offer important passive cooling measures and additional co-benefits.

Parks, trees, water bodies and green infrastructure - such as green roofs – can have significant cooling effects and also help biodiversity and air quality.

The committe recommended the government must adopt a range of these measures, particularly in areas where the ‘urban heat island’ effect typically raises temperatures: for example, London can be up to 8°C warmer than surrounding rural areas.

Over 4.6 million English homes experience summertime overheating, and with 80% of homes that will exist in 2050 having already been built, retrofitting for net zero and thermal comfort will be needed on a vast scale.

Existing initiatives on insulation and energy efficiency should be developed into a national retrofit programme which should be delivered by local authorities, supported by long term funding, focusing on insulation and ventilation, as well as passive measures, above active cooling mechanisms.

Fans may also have a role, and the Government should consider amending Building Regulations to encourage the use of ceiling fans. The Government must urgently bring forward proposals to encourage access to low-cost finance for householders to retrofit passive cooling measures.

Some of the passive measures EAC heard about included installing external shutters, which could reduce incidences of heat mortality by around 40%, and coating the roofs of buildings with reflective white paint.

Environmental Audit Committee Chair, Philip Dunne, MP, said: “The world is heating up, and in the coming year we may exceed an increase of over 1.5°C above pre-industrial levels: breaking a key ambition of the Paris Agreement. The record temperatures we are seeing in UK summers, triggered by climate change, pose significant risks to health and wellbeing, and swift action must now be taken to adapt to the UK’s changing climate."

“Projections suggest that without action, there could be 10,000 UK heat-related deaths annually. High temperatures are costing the UK economy £60 billion a year: so measures to address the risks from overheating are simply a no-brainer. There are a number of relatively simple ways to mitigate overheating risk, such as installing shutters, increasing the size of green spaces and using reflective paint on roofs. Yet none of these measures are being rolled out at scale. There is now a real opportunity to focus on these measures in tandem with improving the energy efficiency of the country’s homes in a new national retrofit programme," Philip Dunne said.

“Tackling overheating at scale will not be a quick or easy undertaking. Clear collaboration between Government departments and local authorities is necessary, supported by a clear messaging campaign and a pipeline of funding and skilled retrofitters to undertake the work needed. Existing Government policy fails to grasp the urgency of the task at hand. A Minister with oversight on heat resilience must be appointed to oversee this important work," he said.

Radhika Khosla, Associate Professor at the Smith School of Enterprise and Environment, University of Oxford, who acted as Specialist Adviser for the EAC’s inquiry, said: “We were delighted to partner with the EAC for this timely and important inquiry. Sustainable cooling has rightly been pushed up the global agenda in recent years as temperatures rise around the world. But now that we recognise the problems from extreme heat, it is imperative we commit to the solutions. Our hope is that this report helps the UK take action to meet its Global Cooling Pledge commitments and, most importantly, helps to save lives and protect people’s wellbeing while reducing emissions from cooling.”