New Barclays research finds more than a quarter of small businesses lost productivity to this summer’s heat, while almost half of large companies say it worked in their favour. With six in ten firms now budgeting for cooling, hot weather has quietly become a line item rather than a talking point.
What the research found
Barclays surveyed 1,000 business leaders through Opinium in late July, alongside 2,000 consumers and hundreds of millions of its own card transactions. The headline number: around 60% of UK firms are investing, or planning to invest, in heat-adaptation technology — cooling, ventilation, building fabric and energy management.
The behavioural changes are already visible on the ground:
- 28% have introduced wellbeing measures during hot spells, including extra breaks
- 23% now offer flexible hours or remote working when temperatures climb
- 21% have shifted core working hours outright
The bit that should worry smaller businesses
More than a quarter of small businesses reported that high temperatures damaged productivity. Among large enterprises, close to half reported a positive effect.
That gap is not about resilience or management quality. It is about capital. Large firms occupy air-conditioned offices, run established flexible-working systems and can absorb the cost of retrofitting a building. A café, a workshop, a small warehouse or a shop with a single-glazed frontage absorbs the heat directly — and the cost of this is in output, sickness, and staff who cannot concentrate past 2pm.
Heat, in other words, is behaving like every other input cost of the last three years: it lands hardest on the businesses least able to spread it.
Your customers have a temperature at which they stay home
Barclays put a number on something retailers and hospitality operators have long suspected. Using transaction data, it found:
- Above 25.1°C, consumers avoid going out to shop
- Above 24.2°C, they resist commuting to work
Note how low those thresholds are. These are not heatwave figures — 25°C is an ordinary summer afternoon. On a hot Tuesday, footfall does not merely soften; it moves. Spend shifts to drinks, cooling products and outdoor venues, and it shifts later in the day.
For anyone forecasting weekly takings on a fixed pattern, that is a planning problem rather than a weather complaint.
Some sectors are getting a boom
Barclays recorded a 4.3% year-on-year rise in banked receipts among air-conditioning firms in Q2 — one of the clearer signs that a domestic climate-adaptation market is forming.
It is not just air conditioning. Installers, ventilation specialists, blind and shading suppliers, insulation firms, refrigeration engineers and commercial electricians are all downstream of that 60% investment figure. If you sell into commercial premises, the retrofit conversation has changed shape.
Why this summer, and why it will not be the last one
The Met Office recorded a UK mean temperature of 16.48°C between 1 June and 10 August — 1.88°C above average, and 2.46°C above average in England. Peaks hit 38°C in June and 35°C on three separate occasions across May and July. At the halfway point, forecasters said the warmest UK summer on record was “increasingly likely”.
The point for business planning is straightforward: a summer like this is no longer the outlier you write off in the accounts.
Where you stand legally
There is no statutory maximum workplace temperature in the UK, and the HSE’s position is that no meaningful upper limit can be set, because heat is often generated by the work itself rather than the weather.
What does exist is a duty. The Workplace (Health, Safety and Welfare) Regulations 1992 require a “reasonable” indoor temperature — with a stated minimum of 16°C, or 13°C for strenuous work, but no ceiling. Under the Health and Safety at Work Act 1974 and the Management of Health and Safety at Work Regulations 1999, you must assess the risk and control it so far as is reasonably practicable.
Two developments are worth watching. The HSE is reviewing its Approved Code of Practice on workplace temperature and will consult publicly. And the Climate Change Committee has recommended introducing maximum temperature regulations — a proposal the government has not yet responded to.
If a legal ceiling does arrive, the firms that already logged a heat risk assessment will find it a formality. The rest will be retrofitting under a deadline.
What to actually do before next summer
Write the risk assessment now. It is already required, it costs nothing but an hour, and it is the document that protects you if a member of staff falls ill.
Cost the cheap fixes first. Shading, reflective film, blinds, fans, relaxed dress code, hydration, rotating staff away from the hottest positions and moving physical work to mornings all reduce risk before you spend anything on plant.
Model your demand curve against temperature. If you are consumer-facing, pull last summer’s daily takings against daily temperatures. If sales fall off a cliff at 25°C, your staffing rota and your delivery slots should reflect that rather than fight it.
Treat cooling as capital expenditure, not emergency spend. Buying air conditioning in the middle of a July heatwave is the most expensive possible way to buy it — installers are booked, prices are high and you are choosing under pressure. Autumn and winter is when the quotes are competitive.
Get flexible working documented. A quarter of firms are already using flexible hours as a heat response. It is the lowest-cost adaptation available and the one that requires the most notice to implement properly.
The uncomfortable read from the Barclays data is that big companies have found a way to make hot weather work for them, and smaller ones largely have not. That gap will not close by itself — but most of what closes it is cheap, and the cheapest time to buy it is now, in the six months when nobody else is asking.
