Brits are world-class complainers when the weather finally decides to turn tropical. Our homes are designed to bottle up every ounce of heat for the endless grey months, which is great in January - less so when July turns the bedroom into a furnace.
And since most UK houses don’t have air conditioning, what’s left? Sticky nights, sweaty afternoons, and creative DIY cooling.
This guide is packed with simple, science-backed hacks that actually work to take the edge off the heat.
They won’t transform your room into the Arctic, but they will help you sleep, work, and lounge without feeling like you’re melting. And if you fancy a longer-term solution, Heatable has plenty of smarter cooling options up its sleeve.
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🔑 Key Takeaways:
Keep the sun out - curtains or blinds during the day stop rooms from turning into ovens.
Make fans work smarter - pair them with a bowl of ice for budget-friendly evaporative cooling.
Night-time is your friend - crack the windows once it’s cooler outside to flush hot air out.
Think longer term - insulation and reflective blinds help year-round, not just in summer.
Want the real fix? Heat pumps with cooling modes and air conditioning keep you comfortable year round.
Why UK Homes Overheat in Summer
UK houses are built for damp winters, not sizzling summers.
Thick brick walls, cavity insulation and double glazing are brilliant at trapping warmth in January - but once outside temperatures hit 25°C or more, that same setup works against us. Instead of letting heat escape, it bottles it up.
The Met Office explains that sunlight streaming through windows quickly raises indoor temperatures, creating a greenhouse effect. South-facing glass is the worst culprit.
Add to that the everyday heat churned out by ovens, laptops, and even fridges, and your living room starts cooking itself.
Ventilation - or the lack of it - is a major player…
The Energy Saving Trust notes that without proper airflow, hot air gets trapped, turning bedrooms into stuffy ovens.
Scientific basics back this up:
Conduction (heat soaking through walls and roofs)
Radiation (sunlight heating up surfaces)
Convection (warm air circulating inside)
Lofts without decent insulation let heat seep down, while poorly shaded windows supercharge the problem.
Sleep suffers too. A YouGov survey found that 65% of Britons often struggle to sleep when it’s hot, making heatwaves more than just a daytime nuisance. (YouGov, 2019)
And it’s not just about the heat - it’s about humidity. Our short, sharp UK heatwaves are often humid, which makes sweat evaporate less efficiently. That’s why 28°C here feels unbearable compared to 35°C in drier climates.
Both old and new homes suffer. Victorian terraces weren’t designed with airflow in mind, and many modern homes are so airtight for energy efficiency that they lock heat in just as effectively.
The result? By mid-afternoon, you’re living in a slow cooker.
The upside: the Met Office advises that simple tweaks - from shading windows to timing ventilation - can knock 2–5°C off indoor temperatures.
It won’t turn your house into an igloo, but it’s often enough to shift from “suffocating” to “bearable.”
Immediate Cooling Hacks
When the house feels like an oven, you need fixes that work now.
These are quick wins, light on cost, heavy on relief - with a dash of science so you know why they actually work.
1. The fan + ice combo
Stick a bowl of ice (or frozen bottles) in front of a fan. As the air blows over the ice, it cools by evaporation - just like sweat cooling your skin.
The Met Office recommends this trick because it can shave a few degrees off a small room.
A pedestal fan works best, and refreshing the ice every hour keeps things chill. Just don’t overdo it in muggy weather, or you’ll add more humidity than comfort.
2. Block the sun
Glass acts like a magnifying glass, ramping up indoor temps. Closing curtains or blinds during peak sun stops this greenhouse effect.
According to the Energy Saving Trust, blackout or thermal curtains can cut solar gain by up to 80%, which means rooms can stay around 5°C cooler.
3. Windows: shut by day, open by night
It feels counterintuitive, but keeping windows closed from late morning to mid-afternoon (roughly 11 am–3 pm) traps the cooler morning air inside. Once outdoor temps drop in the evening, fling them open.
Even better: open windows on opposite sides of the house to create a cross-breeze.
Pair with fans blowing outward to expel hot air - like giving your house a long exhale. Many people report a 4–6°C drop overnight using this method.
4. Evaporative sheet hack
Hang a damp bedsheet in front of an open window or a fan. As air passes through, it cools through evaporation - essentially a DIY evaporative cooler.
The Energy Saving Trust highlights this as a low-energy hack, though it works best in drier air.
In muggy UK heat, it might feel clammy instead of refreshing, so wring the sheet well to avoid puddles.
5. Kill the hidden heaters
Every gadget pumps out heat: lights, TVs, chargers, even idle laptops. Switch off what you’re not using.
Cook outside or stick to the microwave to avoid oven heat. Houseplants like ferns near windows can also help a little by releasing moisture (natural evaporative cooling).
6. Cool your body directly
If all else fails, target yourself instead of the room. Press a cool pack or damp cloth to pulse points (wrists, neck, ankles).
It won’t change the room temperature, but it will drop your core temperature fast - ideal for better sleep.
The bottom line: These hacks are practical, proven, and tested in real UK homes. Each one on its own might only trim a few degrees, but stack them together and you’ll go from sticky misery to something far more bearable.
Longer-Term Fixes
If heatwaves are your annual nemesis, it’s worth investing in upgrades that make your home cooler in summer and cheaper to heat in winter.
1. Reflective or thermal blinds
Unlike standard curtains, reflective blinds have a metallic or thermal backing that bounces sunlight away before it heats the room.
The Energy Saving Trust notes they can reduce solar gain by 50–70%, while still insulating in winter.
They’re also DIY-friendly - most cost just £20–50 per window. In short: small spend, big year-round payoff.
2. Insulation that works both ways
Insulation isn’t just a winter job. Loft and wall insulation slow down heat transfer, keeping upstairs rooms from turning into saunas.
Studies suggest cavity wall fills or external cladding can lower indoor peaks by as much as 5°C. It works by increasing the home’s thermal mass - meaning walls absorb and release heat more gradually.
⚠️ The catch: if done poorly, it can trap moisture. Always go for breathable, quality materials, and check for available grants to keep costs down.
3. Ventilation upgrades
Hot air needs somewhere to go. Extractor fans, trickle vents, or whole-house mechanical systems improve airflow without you having to constantly crack windows.
Trickle vents are the cheapest option (£100–500 depending on the system) and also help control humidity, making rooms feel cooler and fresher.
Compared to short-term hacks, these are “set and forget” solutions.
4. Draught-proofing
It’s not glamorous, but sealing gaps around doors and windows helps keep cooler air inside in summer (just as it locks in heat during winter).
Self-adhesive strips cost only a few quid but add up to noticeable comfort.
When DIY Isn’t Enough
Fans and blackout blinds will only get you so far. With climate change pushing UK heatwaves higher and longer, sometimes you need proper cooling tech.
Heat pumps with cooling functions
Air-source heat pumps aren’t just winter workhorses - many models can reverse in summer, acting like a fridge for your home by pulling heat out.
According to the Energy Saving Trust, they’re highly efficient, delivering 3–4 units of heat (or cooling) for every unit of electricity used.
Installed costs run between £7,000–15,000, though government grants can significantly reduce this.
Why choose them? Unlike DIY hacks, they give consistent comfort without the humidity spikes you get from fans or damp sheets. And in winter, the same unit keeps your home warm.
Air conditioning options
If you want instant chill, AC is still the classic route:
Portable units: from ~£200, easy to set up, vent hot air through a hose. Downsides: noisy, heavy, and less efficient.
Split systems: from ~£1,000, quieter and more powerful, but need pro installation. They cool whole rooms evenly and look cleaner long-term.
The trade-off? AC units consume far more energy than fans - up to 10x as much - and add to carbon footprints. The Met Office notes that AC is still rare in UK homes, but uptake is climbing as summers heat up.
“Fans and ice bowls are fine for a quick fix, but if you really want year-round comfort, a heat pump or AC unit is the way forward. It’s an investment that pays off every summer.” – Patrick Garner, Heatable
NHS Tips on Staying Cool in Heatwaves
The NHS warns that heat can cause dehydration, heat exhaustion, or stroke. Stay cool by: Having cold showers or damp cloths on skin; eating watery foods like salads; avoiding sun 11 am-3 pm; keeping rooms shaded and ventilated at night; drinking 6-8 glasses of water daily, more if active. If dizzy or confused, seek help fast.
Wrap-up
Give these hacks a whirl next hot spell – they are cheap, effective, and eco-friendly.
But as UK summers intensify, future-proofing with insulation or heat pumps makes sense. Stay cool, and if you need boiler or cooling upgrades, Heatable is here to help.
Next Steps For Your AC Journey:
When planning to install air conditioning for your home, there are several important factors to consider. Make sure to refer to the following guides to help you make informed decisions:
To dive deeper into these topics, head over to our advice section, check out our YouTube channel for informative videos.
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