A hot bed makes a hot night unbearable — your bedding can either trap heat against you or let it escape. Getting the bed right is half the battle of sleeping in a heatwave. Here's how to build a cooler bed.
How cooling bedding actually works
Cooling bedding doesn't refrigerate you — it keeps you cool by being breathable and wicking heat and moisture away instead of trapping them. Heavy, synthetic, or tightly woven materials hold warmth against your skin; light, airy, natural fibres let it escape. The whole goal is to let your body shed heat through the night rather than stewing under an insulating layer.
Best fabrics for sheets
Reach for lightweight natural fibres:
- Cotton — breathable, affordable, and widely available; percale weaves feel especially cool and crisp.
- Linen — exceptionally breathable and moisture-wicking, ideal for hot, humid nights.
- Bamboo — soft, breathable, and good at wicking moisture.
Avoid heavy flannel or non-breathable synthetics in summer. A light, breathable sheet beats an expensive "cooling" product that doesn't let air through.
Ditch the heavy duvet
The single easiest swap: replace a thick winter duvet with a thin summer cover, a light blanket, or just a sheet. A heavy duvet traps a huge amount of body heat. Many people keep a lightweight summer duvet specifically for hot months, or simply sleep under a single breathable sheet during a heatwave.
Mattress toppers
Your mattress can be a hidden heat trap, especially memory foam, which tends to hold warmth. A breathable mattress topper adds an airy layer that lets heat escape rather than building up beneath you. It won't make the bed cold, but combined with breathable sheets and airflow it meaningfully reduces how hot the bed feels. Look for breathable, open-structure toppers rather than dense foam.
Build the whole cool bed
Bedding works best as part of a cooled bedroom:
- Shade and pre-cool the bedroom during the day (see our sleep-in-the-heat guide).
- Use breathable sheets and a thin cover.
- Add a breathable topper if your mattress holds heat.
- Aim a fan across the bed so air moves over you.
- Cool your body with a lukewarm shower before bed.
Quick tricks for extra-hot nights
For the worst nights, some people briefly chill a sheet or pillowcase, use a cool damp cloth on the skin, or place a frozen water bottle near (not against) them. These are short-term boosts on top of good bedding, not replacements for it.
The takeaway
Cooler sleep starts with a cooler bed: breathable natural-fibre sheets, a thin cover instead of a duvet, and a breathable topper if your mattress traps heat. Pair it with a shaded room and a fan for the best heatwave sleep. Check which fans are in stock near you to complete the setup.