UK Workplace Temperature Rules: Heat Rights

The United Kingdom has never had a legal limit on the temperature inside a workplace, although a private member’s bill is strong on getting one. With summer heatwaves becoming the norm, millions of workers are wondering, when does it become too hot to work, and what does the law say?

Quick Facts on UK Workplace Temperature Rules

Question	Answer
Does the UK have any law that sets a maximum temperature at work?	No — not yet
What is the current law?	Workers need to be kept at a “reasonable” and “comfortable” temperature by the employer.
What’s the temperature of the new bill?	The temperature inside the building is 30°C (27°C for strenuous work).
What are the existing laws in Spain to implement?	25°C max for physical labour, 27°C max for office work
Who was the sponsor of the bill?	The Green Party’s MP, Hannah Spence (July 2026),
What is the date of the second reading?	October 2026

What Do UK Workplace Temperature Rules Actually Say Right Now?

The bad news is that UK Workplace Temperature Regulations don’t specify a maximum temperature. The current Health and Safety Executive (HSE) advice is that employers must maintain “reasonable” temperatures in indoor workplaces, and keep the air “clean and fresh,” but it doesn’t specify a temperature.

This is too general, according to critics. If a warehouse has a temperature of 34°C and an office has a temperature of 31°C, the notification of “reasonable temperature” provides insufficient legal safeguards.

The disparity between UK workplace temperature guidelines is even more significant for those who work outdoors, such as construction, delivery and agricultural workers. There’s no limit to the outdoor heat, whatsoever.

The New Bill: What Could Change?

A private members’ bill that was presented in July 2026 by Green Party MP Hannah Spence will remedy the lack. If passed, it would:

Set up an independent advisory body on workplace heat safety
Provide that body with power to make recommendations for change, such as a change in working hours and/or work from home during periods of extreme heat.
Potentially introduce hard temperature limits backed by law

Major trade unions (TUC and Unison) are now supporting the request for a maximum temperature of 30°C in all buildings and 27°C for those roles that involve physical exertion. The second reading of the Bill will take place in October 2026.

27°C, 30°C, 35°C — What Do These Numbers Mean?

Temperature	Significance
27°C	Determines Spain’s maximum amount of time spent sitting in office jobs, and the TUC’s recommended limit for strenuous jobs in the UK.
30°C	The recommended maximum size for general indoor workplaces in the UK, as suggested by TUC and Unison.
35°C	It is a standard suspected to cause serious heat stress, and there is no specific UK legal limit.

At present in the UK, there is no legal distinction between the three; they are just not easy to use but not per se illegal.

Can You Leave Work If It’s Too Hot?

Currently, in the UK, the rules on workplace temperature mean that it’s not really possible to just walk away from the job when it’s hot — unless you can demonstrate that there’s a genuine health and safety risk. However, there are rights for workers:

Ask your employer to complete a risk assessment if you think the heat is a risk
If your employer does not take steps to address the concern, report it to the HSE.
Rest breaks, shade, and water should be provided to outdoor workers.

If heat-related complaints are not taken seriously as a duty of care under the Health and Safety at Work Act 1974, employers may be breaking the law.

Why Businesses Are Pushing Back

Not all people are happy to have a legal cap. The threat of closures or reduced opening times during hot weather can be costly to small business owners, especially in the food service and retail sectors, they say. There are also high initial costs associated with installing an air conditioning system, and in a certain number of instances, planning permission may also be a hurdle.

Those in favour of the bill argue that the demand for heat-related sick days is already costing businesses money, and that better UK workplace heat rules would result in a more efficient workforce.

What Should Workers Do Right Now?

As the bill goes through Parliament, here’s what you can do today:

Record the temperature at the workplace when the temperature is high.
Discuss ventilation, fans, flexible workplaces or working from home with your employer.
If your employer doesn’t respond, contact your union.
Please refer to guidance from HSE at hse.gov.uk for up-to-date responsibilities for employers.
Second reading in the fall of 2026 – if voted yes, protections would move forward quickly.

FAQs on UK Workplace Temperature Rules

Is 30°C legally too hot to work in the UK?

No — There is no legal maximum temperature for workplaces at the present time. The limit trade unions are pushing for is 30°C, which is not yet law.

What is the minimum workplace temperature in the UK?

The HSE’s minimum temperature guidelines for most workplaces are 16°C, or 13°C for physically demanding jobs.

Do outdoor workers have any heat protection?

Not in law. The UK outdoor heat limit is not specified, and employers have a general duty of care.

When might new temperature rules come into force?

The second reading of the bill will be in October 2026. Even if passed, it will establish an advisory body first, meaning that it’s not likely that legally binding limits will be some time away.