How to weatherproof your home for sub-tropical Britain

With projected 40C summers and biblical floods hitting us already, how can you guard against our shift to a sub-tropical climate?

Flood
British summers are likely to regularly see temperatures of above 40C in the future

The mid 13th century ditty Sumer is icumen in is one of our oldest songs. Composed at Reading Abbey in the 1260s, the song is also the first known musical composition featuring a six-part polyphony in the English language. Otherwise known as the Summer Canon, it celebrates the many joys of a British summer: the meadows blooming, cuckoos trilling and all the landscape bursting into glorious life.

In the mid-latitudes of the northern hemisphere, the months of June, July and August have for centuries been celebrated in our culture as the season of carefree relaxation after enduring the dark months of winter. But now the prospect of summer coming in appears to be an increasingly ominous one.  

As we have seen across the country in recent weeks, summer is rapidly becoming the season of heatwaves, wildfires and flash floods. The Met Office’s annual State of the UK climate report, published yesterday, sheds new light on the Great British subtropical summer we must soon learn to live with – and indeed is already upon us.

According to the report (which covers last year), in early August 2020, temperatures hit 34C on six consecutive days, with five “tropical nights” where the mercury did not drop below 20C, making it one of the most significant heatwaves to affect southern England in the past 60 years.

tmg.video.placeholder.alt H-V4VXkPZYo

Even if humanity manages to restrict global warming to 1.5C (when currently we are on course for double that) British summers are likely to regularly see temperatures of above 40C in the future.

And as we have seen on the streets of London in recent days, where patients were evacuated from an East London hospital and homes, roads, and tube stations were deluged, extreme summer flooding events are also becoming more likely as a warmer climate enables the atmosphere to hold more moisture, which then dumps down on us in rainfall. Last year was the third warmest, fifth wettest and eighth sunniest on record for the UK.

“We have already changed the climate, without a doubt,” says Professor Richard Betts, head of climate impact research at the Met Office Hadley Centre. “For now we have to live with the changes that are already here, and adapt to them.”

Betts was one of the authors of the UK’s climate change risk assessment report, which advises the Government and published its latest findings in June. The report highlighted eight risk areas that need urgent attention over the next two years – prominent among them the risk to human health from overheating in buildings as temperatures continue to soar. Last August’s heatwave, for example, led to more than 1,700 deaths across Britain. According to a new report by the Red Cross, heat-related deaths in Britain could triple to about 7,000 annually over the next 30 years.

“I think there is a big change needed in our housing stock particularly around overheating,” says Rachel Brisley, a Yorkshire-based technical director in climate services for JBA Consulting, and co-author of the report. “We are very adaptable as a species and can cope with higher temperatures, but we do need to consider our living environment.”    

One prominent concern is new-build homes that have been heavily insulated to comply with building regulations but in some cases without the adequate ventilation to disperse properly the heat in summer. In recent weeks, some people living in new-build properties have complained about sweltering temperatures as the heat is trapped inside.

“A lot of focus has been on making homes energy efficient, which is a very good thing but we have not been setting ourselves up to deal with heatwaves,” says Betts. “You might have a low carbon home but it could still overheat in summer.”

Air conditioning is another policy dilemma the Government is grappling with as it seeks to improve our housing stock better to cope with the increasingly extreme weather we now face at any time of year. As more homes and businesses require air conditioning units, there is a fear that this will place even greater strain on our energy supply and also further ramp up global temperatures as most units emit refrigerant gases called hydrofluorocarbons, which trap heat in the atmosphere.

Speaking on a recent trip to Britain, US climate envoy John Kerry struck a positive note, saying he was confident we could find a technological solution to such problems, including our increasing reliance on air conditioning. Irish firm Exergyn has recently developed a new type of air conditioner that doesn’t release the damaging gases. These are the sort of technological solutions, predicts Kerry, which can cut up to 50 per cent of future emissions.

Our homes will also change in other ways. Brisley says we should invest in shutters and blinds and on extremely hot days fight our instincts by keeping the windows firmly closed. Pale choice of paint colours will reflect the light and heat rather than absorbing them, and some experts advise fitting a protective film to windows to filter UV rays from the sun.

Increased flood risk, too, will also require a rethink of the layout of our homes. In properties at risk of flooding, experts advise moving plug sockets high up the walls, replacing the lower steps on a flight of stairs with concrete instead of wood, pulling up ground floor carpets and tiling with waterproof adhesive and grout, using water-resistant plaster, placing appliances such as fridges and water tanks on raised plinths and having a wall-mounted television.

The issue is cost. In 2017, the Building Research Establishment estimated the total outlay of creating a fully flood-resistant home to be about £60,000. Currently, this money is often made available in grants following extreme flooding events, although it is widely agreed we need to be far more proactive in transforming our housing stock.

In parts of the country particularly prone to flooding, this is already happening – the Calder Valley town of Hebden Bridge, for example, which has endured repeated flooding in the past decade and where the Government yesterday announced it would spend £4.4m improving defences as part of £5.2bn plans to improve protection for 336,000 English properties over the next six years.

Here, high street shop owners have already taken matters into their own hands, installing concrete floors, flood gates, and – in the case of the bookshop – a sign that doubles up as a flood barrier.

Ali Haley, 39, who works at Element Jewellery on the high street, says after flooding in 2015, which left the shop closed for 111 days, they have installed concrete floors, replaced wooden cabinets with ones constructed out of powder-coated steel, stripped one wall to bare brick and used waterproof render on the others and created removable window displays made out of marine ply.

When the shop flooded in February 2020, they were open again in three days. “It is a huge relief,” says Haley. “You do feel as if you have a bit more security.”

Dr Pam Berry, senior research fellow at Oxford University’s Environmental Change Institute, says there are other more low-scale changes we can all do. Planting more trees in our gardens and on our high streets, for example, provides shelter from extreme heat and reduces flood risk.

Green roofs and walls lower temperatures in our houses, while keeping gardens planted with vegetation and ponds rather than paved over or replaced with plastic grass reduces water run-off and the risk of surface flooding.

These are solutions, says Berry, which help address the biodiversity crisis as well as increasing our resilience to the unfamiliar weather rapidly engulfing us. And with greener streets and frogs croaking their own pond polyphonies, summer in sub-tropical Britain need not be all that bad.

Forecast: a Diary of the Lost Seasons by Joe Shute is available from Telegraph Books for £16.99. To order, visit books.telegraph.co.uk or call 0844 871 1514

License this content