The issue is already having an economic impact. Research from the London School of Economics and Political Science’s Grantham Research Institute found that the June 2026 heatwave resulted in an estimated 24 million lost working hours and £1.15 billion in lost economic output.

The study, based on a nationally representative survey of 1,950 adults, found that 87% of respondents experienced at least one health impact during the heatwave. Around 3.6% reported that they had not worked at all during the week, while the effects were particularly pronounced among people working outdoors or in physically demanding roles.

The findings come as The Physiological Society calls for a more consistent approach to protecting workers from extreme heat. Its new report points to the need for clearer heat thresholds, updated regulations and employer guidance, alongside greater consideration of how the human body responds to high temperatures.

The health implications also extend beyond individual workplaces. According to the report, heat-related impacts on the UK health sector currently cost around £538 million each year. This figure could increase by 245% by the 2050s as temperatures rise and heatwaves become more frequent.

For facilities and workplace teams, managing heat presents a practical challenge. Keeping a building cool involves much more than adjusting the air conditioning. Building design, ventilation, shading, occupancy, equipment, working patterns and the physical demands placed on employees can all affect how people experience heat.

The Health and Safety Executive does not set a maximum workplace temperature in UK law. Employers are required to provide a reasonable indoor temperature and assess risks where working conditions could affect employees' health and safety. HSE guidance also makes clear that thermal comfort depends on factors including air temperature, humidity, air movement, radiant heat, clothing and workload.

That means facilities teams may need to consider a range of measures during periods of extreme heat. These can include improving ventilation and air conditioning, providing shading, allowing more flexible working hours, increasing access to drinking water and rest breaks, and reviewing working arrangements for people particularly exposed to heat.

There is also a longer-term planning issue for organisations. The UK is expected to experience more frequent periods of extreme heat as the climate changes, putting additional pressure on buildings and the systems responsible for maintaining suitable working conditions.

For facilities managers, this makes heat resilience an increasingly relevant part of workplace planning. Understanding how buildings perform during extreme weather, identifying where employees are most exposed and having practical measures ready before temperatures rise can all help reduce the impact on people and operations.

The latest research suggests that extreme heat is already affecting how much people can work and the conditions in which they work. As hot weather becomes a more regular consideration for UK organisations, workplace and facilities teams will have an important role in preparing buildings, policies and working practices for it.

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