As we move into another summer heatwave, BESA technical director Kevin Morrissey says we need to urgently rethink how we deal with overheating buildings.
UK heatwaves are becoming more frequent and intense, which has major implications for health, well-being and productivity. In fact, extreme heat has been identified as the “silent killer” of climate change and overheating as our “most overlooked building safety issue”.
Therefore, BESA is urging the government to re-set the Boiler Upgrade Scheme (BUS), which is currently under review, to include incentives for air-to-air heat pumps that provide cooling as well as heating.
Not only could this help to tackle overheating but would also fuel additional market growth and help to reduce carbon emissions as part of a wider programme of building retrofits that includes a range of cooling methods like smart controls and solar shading.
It is a major drawback that this support is not already available, and this change could help to address the disappointingly slow roll out of heat pump installations, which are still far below the government’s targets. Also, the social and economic benefits would mean this taxpayer funding would quickly pay for itself.
Risks from overheating and poor air quality
BESA members have been sounding the alarm bells about overheating and the related risks of poor air quality in buildings for years. Their lobbying, technical guidance and day-to-day activities place building engineering firms at the forefront of efforts to provide a safer, healthier and more comfortable built environment for all.
A recent study found that 80% of UK homes overheat in the summer and the government reported that UK summertime temperatures are projected to be between 1.3°C and 5.1°C warmer over the coming decades. So, with the transformation of our climate and environment already locked in there is clearly much to do to address the growing impact of our warmer summers.
Whilst thermal comfort is important, the bigger issue here is that overheating impacts people’s productivity, attainment, wellbeing, and health, and can be fatal. The summer heat waves of 2022 saw an estimated 2,985 excess deaths, but the London School of Hygiene and Tropical Medicine (LSHTM) believes that was an underestimate because heat is not always recorded as a cause of death where there is a pre-existing health condition.
The British Medical Journal adds that annual heat related deaths across the UK could exceed 10,000 by 2050.
Part of the reason for this dramatic increase is that whilst government investment is addressing other impacts of climate change, such as investment on flood defences, much of the progress is “either too slow, has stalled, or is heading in the wrong direction”. This has led some commentators, including Dr Akshay Deoras, of the University of Reading, to observe that “If floods and storms are the loud alarms of climate change, extreme heat is its silent killer. It is disproportionately lethal, often going unnoticed until it’s too late”.
The inequality in the effects of heat is highlighted by the LSHTM, which notes that exposure to temperature in the high 20s and low 30s can be fatal for people over 65, infants, pregnant people, and those with existing health conditions.
Socioeconomic factors also contribute to the risk profile and the outcome for vulnerable populations, such as those who live or work in poor quality homes and buildings across the UK. They are just as exposed to the impact of excess heat in the summer as cold in the winter.
However, heat related deaths are not the exclusive domain of the poorer members of society or those in social housing. Heat can also be fatal for anyone suffering from common health conditions including heart disease, diabetes, and respiratory issues.
It is heartening that influential bodies like the All Party Parliamentary Group for Healthy Homes and Buildings, which BESA sponsors, are taking a lead on addressing some of the issues with government, but other policies and public sector programmes may be making the problem worse.
As well as the current BUS, the Warm Homes Plan and the Great British Insulation Scheme are aimed at reshaping how we heat buildings. While better insulation may have a positive impact on heating bills, the improved thermal performance also traps heat and moisture compounding the risk of overheating, damp, mould and poor air quality, all of which exacerbate health issues and increase the risk of mortality.
Radically reshaped regulator
The UK’s building safety regime, reshaped in the wake of the Grenfell Tower tragedy, has quite rightly focused heavily on fire safety, and recent changes to The Building Safety Regulator (BSR), have reinforced this through the appointment of a new leadership team whose experience and background is very firmly rooted in fire safety.
Whilst changes at the BSR have been made to address project delays and Gateway holdups, it is crucial that any “fast tracking” of the planning process and the necessary focus on safety, does not compromise other aspects of occupant health and well-being. It is encouraging that the reformed BSR has recognised the role of specialists in providing a comprehensive and integrated approach, which BESA members are ready to support with effective and efficient cooling and ventilation services.
The UK has an historic antipathy to residential air conditioning as many still believe we live in a cold country. Recent summers suggest otherwise and, while prominent figures like London Mayor Sadiq Khan, are still calling for better ventilation rather than cooling, it may be time to recognise the limitations of this approach against the backdrop of climate change, rising temperatures, the growing impact of air and noise pollution.
Better ventilation did prove its worth during the Covid-19 pandemic when the transmission of disease in poorly ventilated indoor spaces was found to be one of the most significant factors in its spread. This prompted Professor Cath Noakes, a prominent member of the government’s Scientific Advisory Group for Emergencies (SAGE), to describe lack of ventilation as the “most overlooked building safety issue”.
So, the question for our industry is how we make best use of our knowledge and existing solutions to meet much wider health and social goals. And, if we are looking to increase the use of heat pump technology to deal with what are likely to be shorter heating seasons, why don’t we embrace that technology to provide cooling that also enhances ventilation strategies?
Yes, there are still big issues around electricity generation and grid capacity, but the continued increase in renewable generation and upgrading of the national grid will help resolve the carbon emissions and infrastructural challenges.
Mechanical cooling/air conditioning is not a panacea, it needs to be deployed in conjunction with other initiatives, such as shading. There are also health risks associated with its use and overuse, especially if not properly maintained and operated.
There is still the risk that demand for cooling reverses the direction of travel on carbon reduction and fuel poverty, but smart controls and metering coupled with tariff adjustment for general consumers, could be used to shape behaviours and use, while targeted Summer Cool Payments could help protect vulnerable people at risk.
If we are all now feeling the heat, surely, it’s time to rethink how to be cool.
Sources of further reading:
UEL study finds 80% of UK homes overheat in summer | University of East London
Climate change explained - GOV.UK
Environment Agency climate adaptation reporting fourth round: climate resilience for a better environment - GOV.UK
Nearly 600 heat-related deaths expected in UK heatwave, researchers estimate |
Climate change: UK is unprepared for rising deaths and health disruption, report warns |
The BMJ Government not taking climate threats seriously - watchdog - BBC News
Projections of heat related mortality under combined climate and socioeconomic adaptation scenarios for England and Wales | PLOS Climate