Are UK Homes Ready for a Hotter Climate?

Are UK homes designed for summers as hot as this?

There is something uniquely British about spending the summer complaining that it is too hot, while simultaneously knowing that by October we will probably be complaining that it is too cold.

But this year, the heat has felt different.

For many of us, the combination of high temperatures and humidity has made homes feel less like a place to escape the heat and more like somewhere that is determined to hold onto it. Fans are brought out of storage and the familiar British advice of “just open a window” starts to feel considerably less useful when the air outside is warm and heavy too.

It raises an interesting question: are our homes designed for the summers we are beginning to experience?

A country built for keeping warm

For generations, the priority in UK housing has been relatively straightforward: keep the warmth in.

We have traditionally had a cool, damp climate, with long periods where heating our homes is far more important than cooling them. Our building stock reflects that history.

In fact, the UK has one of the oldest housing stocks in Europe. Research from the Resolution Foundation found that 38% of homes were built before 1946, the highest proportion of any European country.

These homes were designed for a very different set of environmental conditions and, in many cases, long before overheating was a significant consideration in residential design.

Now, the challenge is becoming two-sided.

We still need homes that can retain heat efficiently during winter, but we increasingly need them to be capable of shedding unwanted heat during summer.

And that is a much more complicated problem than simply turning the heating off.

The heat is already making an impact

The Met Office recorded three distinct UK heatwaves by July this year, with temperatures reaching 35°C or above in May, June and July for the first time in the UK weather record. By July, eight days had already exceeded 34°C, surpassing the previous record held by 1976 and 2020.

Heat is also about more than the number on the thermometer. Humidity and a lack of overnight cooling can make hot weather considerably more uncomfortable, particularly indoors. During June’s exceptional heat, the Met Office highlighted the combination of high humidity and limited overnight cooling as a factor contributing to heat stress.

And this is where the issue becomes particularly relevant to the built environment. The Climate Change Committee’s latest assessment warns that, by 2050, 92% of existing UK homes could be at risk of overheating under a 2°C global warming scenario.

That is a remarkable figure, suggesting that overheating is not simply a problem for a handful of exceptionally hot days. It is something that needs to be considered when we think about the long-term performance of our homes.

Is air conditioning the answer?

The obvious response to hotter summers is, of course, air conditioning. For anyone who has spent a humid night trying to sleep in a room that feels warmer than it should, the appeal is obvious. But widespread air conditioning also brings questions around energy demand, household costs and the pressure placed on the wider electricity network.

Around one million of England’s 25 million homes currently have air conditioning, with research from the University of Reading suggesting this could rise to 18 million by 2050 as summers become hotter.

Rather than simply relying on mechanical cooling, however, there is a growing case for considering how buildings can be designed to manage heat before air conditioning becomes necessary.

Designing for summer as well as winter

This is where building design has an increasingly important role to play. Orientation, glazing, shading and ventilation can all influence how a home responds to hot weather, helping to reduce solar gain and allow heat to escape when conditions are cooler.

These passive approaches do not mean air conditioning has no place, but they do encourage us to think about cooling as part of the building’s design rather than something that is added later. If we can reduce the amount of heat entering a property in the first place, we may also reduce how much mechanical cooling is needed to make it comfortable.

The bigger challenge: existing homes

New homes can be designed with future conditions in mind, but we cannot simply replace the UK’s existing housing stock every time the climate changes. Millions of properties were built decades or even centuries ago, and many will present significant challenges when it comes to adapting them for hotter summers.

The Climate Change Committee’s projection that 92% of existing homes could be at risk of overheating by 2050 highlights the scale of the challenge. Addressing it will require a long-term approach to improving the performance of existing buildings, while recognising that what works for a modern new-build may not always be practical or appropriate for an older property.

That makes the question of how we adapt the homes we already have just as important as how we design the ones we are yet to build.

What does a future-proof home look like?

For a long time, conversations around future-proofing homes have focused on energy efficiency, insulation and reducing heat loss. Those things remain important, but perhaps future-proofing now needs to mean something broader.

A home should not only be able to keep its occupants warm through a cold winter; increasingly, it needs to remain comfortable through periods of extreme heat too. That does not necessarily mean every British home needs air conditioning. In fact, perhaps the long-term answer is almost the opposite: the homes of the future may be the ones designed to need less mechanical cooling in the first place.

As we continue to build new homes and adapt the ones already standing, the challenge will be finding the right balance between efficiency, comfort, practicality and resilience. Because if this summer has taught us anything, it is that the British weather is not always quite as predictable as we like to think.

Perhaps the question we should be asking is no longer simply whether our homes are ready for winter.

Are they ready for summer too?