The UK’s climate has flipped. Scorching summers are now more common than harsh winters, yet our buildings remain stubbornly rooted in a colder past, writes Kevin Morrissey.
I appreciated the opportunity to be quoted in The Times last week as someone with ideas about how we should adapt our built environment to cope with a warming climate. However, due to the normal pressures on space in the national print media, my comments were somewhat truncated.
“Morrissey at BESA conceded that air conditioning and ventilation were ‘not a panacea’. Keeping homes cool would also involve shade from awnings and trees, Mediterranean-style shutters, and other things.”
In his famous speech about putting a man on the Moon, then US President John F. Kennedy said: “We choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard.”
There was much speculation at the time about what he was referring to. While not claiming a similar level of public interest in the utterances of BESA’s technical director, the curious Times reader might similarly wonder: “What are these other things?”
The list is extensive and varied because adapting to a warming climate, like putting a man on the Moon, is hard. It is also getting harder because the impact of climate change is accelerating. The Met Office is already forecasting another heatwave for next week.
Overheating Homes
It requires a rounded, holistic approach that combines government policy with technical solutions and incentives to change behaviour. However, to succeed, we must finally accept that we no longer live in a cold country.
Successive governments have prepared Britain for a climate model that no longer exists. The result is a nation of overheating homes that were never designed to keep people cool.
Research suggests that 80% of UK homes overheat during the summer, while the British Medical Journal reports that annual heat-related deaths across the UK could exceed 10,000 by 2050.
The World Meteorological Organization also says there have already been more than 1,300 excess deaths across Europe since 21 June this year linked to extreme heat.
BESA members and specialist firms registered with the cooling industry scheme REFCOM, which the Association manages, have been sounding the alarm about overheating and the related risks of poor indoor air quality for years. However, government policy has remained rooted in the belief that we still live in a cold country.
The first sign of a modest shift came late last year, when the government announced that it would expand the Boiler Upgrade Scheme (BUS), which has been helping consumers switch from boilers to heat pumps.
This expansion included air-to-air heat pumps, which can provide cooling and air conditioning for homes as well as heating.
However, the latest government figures show that, up to May 2026, no air-to-air heat pump installations had been carried out through the BUS scheme.
While the expansion was clearly a step in the right direction, as with many other government initiatives, there was little advance warning. As a result, the frameworks needed to deliver it are still catching up.
These frameworks also demand higher levels of competence, so individuals and businesses must weigh up the advantages of investing in training and upskilling against the potential risks.
There is understandably a trust issue. MEP businesses have seen previous government-backed schemes come and go, including the ECO scheme, which provided full heat pump funding for lower-income households but was scrapped following poor-quality work on insulation upgrades that it also funded.
Responsible businesses that invest in training and developing their people are all too aware that the benefits may be short-lived if funding is withdrawn when a current or future government needs to make savings.
Heat pumps have, in effect, become a victim of the fallout from the insulation scandal, and a replacement for the ECO scheme is urgently needed.
Measures to reduce running costs by addressing the unfair burden of subsidies levied on electricity bills are also vital.
Narrowing the “spark gap” between electricity and gas is fundamental because energy-efficient electrical systems such as heat pumps are currently being unfairly penalised.
Households pay around four times more for a unit of electricity than for gas, which is proving to be one of the biggest barriers to the UK’s plans for the decarbonisation of heating and cooling.
Policies Must Reflect A Warmer Climate
It is heartening that influential bodies such as the All-Party Parliamentary Group for Healthy Homes and Buildings, of which BESA is a sponsor, are taking a lead in addressing some of these issues with government. However, other policies and public-sector programmes may be making the problem worse.
The Warm Homes Plan and the Great British Insulation Scheme are intended to reshape how we heat buildings. While better insulation may help to reduce heating bills, improved thermal performance can also trap heat and moisture.
This compounds the risk of overheating, damp, mould and poor indoor air quality, all of which can exacerbate health issues and increase mortality.
The Future Homes Standard does at least work alongside Building Regulations Part O (Overheating), which sets mandatory requirements designed to prevent homes from becoming excessively hot.
These include improved ventilation to remove heat, limits on solar gain through the building fabric using passive measures, and compliance modelling aimed at ensuring developers meet overheating standards.
However, these measures apply only to new homes and, as the government is well aware, we do not build enough of them.
Part O came into force only in 2022, so anything already designed and under construction before then may be unsuited to the hotter weather we now experience.
This includes thousands of relatively recently built, heavily glazed high-rise buildings with overheating apartments and enclosed internal corridors that become dangerously hot.
We have effectively built a generation of tall buildings that could become uninhabitable during summer heatwaves by the middle of the century.
Overheating is part of a wider health and safety crisis that is not properly reflected in current policy or in the new building safety regime introduced following the Grenfell Tower disaster.
However, reforming grant funding and addressing the spark gap could trigger a wider national retrofit strategy that improves the health-related performance of homes through whole-house upgrades. This could be achieved relatively quickly.
Solar panels also perform best during summer conditions, so much of the electricity they generate could be used to power heat pumps and other forms of electrical air conditioning when they are needed most.
Ventilation and air conditioning systems, where installed, also require initial verification followed by maintenance and monitoring throughout their operational life.
Many indoor air quality and overheating problems, including damp, mould and the resulting health and wellbeing issues, begin with a tick-box exercise at handover.
This confirms that a system has been installed, rather than verifying whether it will maintain a comfortable, healthy and safe environment throughout its operating lifetime.
Competence, Controls And Maintenance
Consider the problems experienced with mechanical ventilation with heat recovery (MVHR) systems. Thousands were installed by unqualified operators, never properly explained to homeowners and never maintained.
However, smart controls and metering, coupled with tariff adjustments for consumers, could be used to shape behaviour and energy-use patterns.
We already have Winter Fuel Payments for people at risk from cold, so why not introduce targeted Summer Cool Payments for those most vulnerable to the effects of overheating, helping to make mechanical cooling more affordable?
There are, therefore, many things on the to-do list. Admittedly, many are aimed at accelerating the deployment of heat pumps and possibly air conditioning, but they could also support a properly planned focus on whole-house retrofitting and maintenance.
Just as insulation programmes were intended to reduce demand for heating, retrofitting buildings with renewably powered heat pumps, ventilation and passive measures could reduce the amount of energy needed to keep them cool.
In this way, a new cooling strategy could move alongside the drive to decarbonise buildings on the road to net zero.