If it feels like this summer just won't let up, you're not imagining it. The UK has seen a run of heatwaves since May, with the Met Office confirming one of the longest stretches of 30°C+ days since 1976 and amber heat-health alerts across England well into July. Across the Channel, France and much of Western Europe have been sitting under a stubborn heat dome, with temperatures pushing into the low-to-mid 40s°Cs in the worst-hit regions. If you don't have central air, none of that is comfortable to sit through.
The good news: you don't need central AC to make a real difference in how a room feels. You need to stop heat getting in, and then move or condition the air that's already inside. Here's how to do both.
Start with what's coming through the glass
A huge share of the heat in any room enters through the windows, especially on a south- or west-facing wall in direct sun. Before you even think about a fan or a cooler, it's worth blocking that heat at the source. A Reflective Thermal Window Shade reflects sunlight back outside the glass rather than letting it hit your furniture and warm the room from the inside out, and it's a five-minute, no-tools install. For rooms that get hit hardest, a Blackout Window Insulation Aluminum Panel goes a step further, cutting out roughly 90% of incoming light and heat. We go deeper on this in our window insulation guide if you want the full breakdown.
Evaporative cooling for a single room
Once the heat gain is under control, the next move is evaporative cooling — pulling warm air through a water-saturated pad so it comes out the other side genuinely cooler and slightly humidified, not just moved around. For a bedroom, home office, or living room, our 3-in-1 Portable Evaporative Swamp Cooler is built for exactly this: it covers rooms over 300 sq ft, runs as a straight fan when you don't need the mist, and doubles as a humidifier in drier weather.
Full-size cooling without a single duct
If you want the closest thing to AC-level coverage for a living room or open-plan space, the Leafless Water-Cooled Air Chiller is our largest unit — fill the 3-litre tank and it pushes evaporatively cooled air across the room, bladeless, with a remote for adjusting from the sofa.
Putting it together
The rooms that stay coolest through a heatwave usually combine both moves: heat blocked at the window, plus a cooler doing the work inside. If you're also noticing the air feeling heavy or damp once you're running an evaporative cooler for hours a day, that's normal — it's worth reading our dehumidifier buying guide to keep the balance right. And if the heat is mainly a problem at your desk rather than the whole room, our guide to staying cool while you work covers smaller, closer-range options.
Frequently Asked Questions
Does an evaporative cooler actually lower room temperature, or does it just move air around?
It genuinely cools the air passing through it, using a fan pulling air through a water-saturated pad, so the output is measurably cooler than the room — not just recirculated warm air like a standard fan.
Do evaporative coolers work as well in humid weather as dry weather?
No. Evaporative cooling works best in low humidity. In muggy conditions the air is already close to saturated, so less water can evaporate and the cooling effect is smaller. On the most humid days, pairing one with a dehumidifier helps.
Is an evaporative cooler cheaper to run than air conditioning?
Yes, meaningfully. Evaporative coolers use a fan motor and a small water pump rather than a compressor, so they draw a fraction of the electricity a refrigerant-based AC unit needs.
Do I need to vent an evaporative cooler outside like a portable AC?
No. That's one of the main advantages over a portable air conditioner, which needs an exhaust hose through a window. Our evaporative coolers just need a water fill.
What's the single most effective first step if a room won't cool down?
Block the sun at the window before adding any cooling device. A room that never heats up in the first place needs far less work to cool afterward — see our window insulation guide.