UP TO 10,000 extreme heat deaths are predicted by 2050 as Britain was “built for a climate that no longer exists,” MPs have warned.

The environmental audit committee urged the government to climate-proof schools, hospitals, care homes and prisons despite a “significant” £11 billion annual cost.

In a letter to the government published today, committee chairman and Labour MP Toby Perkins said: “Taking action carries a significant cost. But the cost of doing nothing is far, far greater.

“Without action, we will see economic productivity take a hit; more people needing attention in hospital and suffering with poor mental health; more hospitals, care homes and schools overheating and more of our critical transport, water, food and IT systems failing. 

“Economic productivity will be hit, but more importantly we will likely see a significant number of deaths as a direct result of the current heatwave.

“The evidence could not be clearer that extreme heat is an urgent threat to Britain. 

“Yet the government is currently falling ‘far short of what is needed,’ according to its independent climate advisers.”

He demanded the government explain what action it is taking to “tackle extreme overheating, a problem that will only grow worse without intervention, as well as its views on important measures to adapt to what seems to be our new normal.”

Government climate advisers warned the committee that temperatures could top 43°C and see as many as 10,000 excess deaths in Britain by 2050.

Professor Swenja Surminski, of the Climate Change Committee, stressed that Britain “has been built for a climate that no longer exists.”

“Our analysis shows that the cost of inaction is far greater than taking action” — estimated at an annual average of £11bn until 2050.

NASUWT general secretary Matt Wrack told the Morning Star: “It is clear that significant and wide-ranging actions are needed to deal with the reality of a warming climate and to mitigate the impact on schools and pupils’ education. Doing nothing is not an option. 

“The suggestion that the exam season should be shifted outside of the summer months would need careful consideration as this would have a host of knock on impacts on the curriculum, the school year and on pupils’ destinations after school.” 

British Medical Association representative body chair Dr Amit Kochhar warned many hospital and GP practices are “outdated; in desperate need of modernising.”

With one in five GP surgeries predating the foundation of the NHS in 1948, he added: “In extreme temperatures like we’re experiencing this week or at the other end of the spectrum in the depths of winter, this can cause real problems for both staff trying to work comfortably and safely, and for patients being treated or waiting to be seen — in some cases for health conditions related to the temperature itself.”

Unison assistant general secretary Jon Richards said: “Public-sector workers can’t simply stop when temperatures soar.

“Paramedics still answer emergency calls. Care workers carry on supporting vulnerable people. And thousands of NHS, council, school and police staff still have vital jobs to do. 

“But as heatwaves become more common, employers must ensure workplaces remain safe.”

Yesterday unions, campaigners and Green Party leader Zack Polanski warned the likely next prime minister, Andy Burnham, against backsliding on climate action, amid speculation he could make former health secretary Wes Streeting his chancellor. Mr Streeting has backed drilling for more North Sea oil and gas.

National Education Union general secretary Daniel Kebede said: “This week’s extreme heatwave is causing untold disruption and discomfort throughout our education system. 

“This certainly isn’t the moment to move away from trying to tackle the very causes of what we are experiencing this week; if we make that mistake, these episodes will only continue to get worse.”

Fire Brigades Union general secretary Steve Wright added: “We see first-hand the need for urgent climate action and that must include restrictions on drilling in the North Sea.

“We urgently need a plan for adaptation that protects people’s health as well as the environment.”

Mr Polanski told the Guardian that any move to water down the party’s commitments would have dire consequences at the ballot box.

Janet Newsham, chair of the Hazards Campaign, said: “Thousands of people die each year because of exposure to extreme heat and  it is only going to get worse as climate risks increase.

“Therefore the government must respond to the climate emergency, they must ensure that publicly owned buildings are adapted to ensure good ventilation and cool air.”

The Department for the Environment, Food and Rural Affairs was contacted for comment.