Climate advisers urge workplace heat cap

The Climate Change Committee has called for the UK to introduce a national maximum workplace temperature, arguing that rising heat exposure now requires a clearer legal standard rather than broad guidance alone.

Published on 20 May, the committee’s latest adaptation assessment, A Well-Adapted UK, says hotter summers are placing growing pressure on workplaces, public services, transport systems, and buildings that were not designed for prolonged high temperatures. The report says the annual likelihood of temperatures exceeding 40°C somewhere in the UK is now around 4%, which is 20 times higher than in the 1960s, and puts the chance of another 40°C day within the next 12 years at 50%.

Among its more direct recommendations, the committee says the government should commit to a maximum temperature for workplaces and set a clear objective that rates of heat-related illness and accidents at work do not rise between now and 2050. While the report ranges across flooding, drought, food systems, and housing, heat is treated as an immediate operational concern that cuts across offices, warehouses, factories, logistics networks, and outdoor work.

Baroness Brown, chair of the Adaptation Committee, said: “Our lives, our landscapes and our homes are under increasing pressure from the changing climate. But we are not powerless.”

That recommendation meets a legal position that remains deliberately broad. Current government guidance states that there is no law setting a minimum or maximum working temperature, while the Health and Safety Executive says employers must keep indoor temperatures at a reasonable level and assess workplace risks, including those created by excessive heat. In practice, the absence of a statutory ceiling has left employers to determine what is reasonable across very different environments, building types, and working patterns.

In foundries, bakeries, on construction sites, and across other heat-exposed settings, the risks are already well understood, yet the report makes clear that the problem no longer sits only in traditionally high-temperature roles. Older office stock, poorly ventilated commercial buildings, urban heat islands, and transport disruption are widening the pressure across the economy, while heat stress itself can bring fatigue, impaired concentration, nausea, loss of consciousness, and, in severe cases, death.

Because much of the response sits in day-to-day operations rather than in abstract planning documents, the committee points to ventilation, external shading, active cooling, hydration, uniforms, rest arrangements, and shift design as practical measures that can reduce exposure. It also notes that in agriculture, starting work two hours earlier in hot weather can reduce productivity losses by up to 33%, a detail that underlines how climate adaptation is beginning to reshape scheduling as much as it reshapes buildings. Those interventions may be simple in isolation, but together they lead into broader questions around capital expenditure, retrofits, insurance, and business continuity.

Elsewhere in Europe, governments have already moved further towards prescriptive controls. The committee highlights Spain, where work activity must be reduced during periods of extreme heat if workers’ health cannot be protected, and that contrast is likely to sharpen debate in the UK as successive hot summers turn temperature management into a recurring boardroom issue rather than an occasional seasonal concern.

Its wider message on adaptation is that delay carries a cost across multiple systems at once. The committee estimates that climate damage to public welfare could reach between 1% and 5% of GDP by 2050 under 2°C of global warming, and says around £11 billion a year in public and private investment will be needed to strengthen resilience. Within that broader picture, workplaces sit at the point where climate policy, health and safety, property strategy, and workforce planning increasingly converge.

Although the committee stops short of proposing a single temperature threshold, and ministers have not committed to legislation, the case for a formal limit has now been placed squarely into the policy debate. At the same time, the report makes a broader argument that adaptation can no longer be treated as a secondary consideration in how organisations design, manage, and protect their daily operations.