How to Cool Down a Room in a Heatwave (UK Guide 2026)

How to Cool Down a Room in a Heatwave (UK Guide 2026)

UK homes are built to keep heat in, not out — which is exactly the problem when it's 32°C outside and your living room feels like a greenhouse. Here's what actually works, roughly in order of "do this first, it's free" through to "buy this if you need serious relief."

1. Block the Sun Before It Gets In (Free)

Close curtains and blinds on any window that gets direct sun during the day — ideally before the room heats up, not after. This single habit can keep a room several degrees cooler than leaving windows uncovered, because you're stopping the heat from getting in rather than trying to remove it once it has. If your current curtains are thin or light-coloured, a proper set of blackout curtains makes a genuinely noticeable difference — they block heat as effectively as they block light.

2. Create a Through-Draught After Dark (Free)

Once it's cooler outside than inside — usually after sunset — open windows at opposite ends of the house to create a genuine cross-breeze rather than just cracking one window. This pulls the accumulated heat out far faster than a single open window ever will. Keep windows shut and curtains closed again first thing in the morning before the outside temperature climbs back up.

3. Turn Off Anything That Generates Heat

Ovens, tumble dryers, and even leaving multiple devices on standby all add heat to a room over the course of a day. Cook on the hob or use an air fryer instead of the oven where you can — it genuinely makes a difference in a small kitchen-diner. Switch off lights you're not using too; incandescent and older halogen bulbs put out more heat than most people realise.

4. Get a Fan (And Use It Properly)

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A fan doesn't lower room temperature, but moving air makes your body feel several degrees cooler through evaporation — which is often all you actually need. Position it to pull in cooler air from a hallway or shaded room rather than just recirculating the same hot air, and if you point it at a bowl of ice or a wet towel, you get a rough evaporative cooling boost for a fraction of the cost of air conditioning.

5. Consider Window Film or a Reflective Shield

A one-way or UV-blocking film applied directly to the glass cuts a meaningful amount of solar heat gain without blocking your view entirely — useful for a conservatory or south-facing window that curtains alone can't tame. It's a one-off application that keeps working every summer after, unlike blinds you have to remember to close.

6. If a Fan Isn't Enough: Portable AC or Dehumidifier

For a genuinely stifling room — a loft conversion, a south-facing box room, or anywhere a fan just isn't cutting it — a portable air conditioner actually lowers the temperature rather than just moving air around. Stock has been tight during this year's heatwaves, so check what's actually orderable before committing to a specific model. A dehumidifier can also help on muggy, humid days since high humidity is a big part of why heat feels so oppressive indoors.

Struggling to sleep too? See our companion guide on how to keep cool in bed during a heatwave. And if it's your sofa turning the living room into a sauna, ours are delivered within 48 hours across Staffordshire and the West Midlands.

Browse Preloved Sofas from £280 →

Looking for more? See our full Home Living Guide for every buying guide on the blog.

Also on the blog: Best Blackout Curtains UK 2026 · Best Dehumidifier UK 2026 · Best Fans UK 2026

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