Action first

How to sleep during a heatwave

Short answer

Keep daytime heat out, then ventilate once outside is cooler. Use light bedding, airflow and cool water for personal relief. If another safe room is cooler, sleep there temporarily.

Before bed

  • ✓Shade sunny bedroom windows during the day.
  • ✓Turn off equipment that adds heat.
  • ✓Once outside is cooler, open safe windows and move air through the home.
  • ✓Prepare cool water and use light bedding and clothing.

If the room stays hot

Walls, roofs and furniture can release stored heat after sunset. Continue safe ventilation while outside remains cooler. Use a fan across people for comfort, or move to a cooler part of the home.

Check the person, not only the room

Look for heat illness

Dizziness, headache, nausea, heavy sweating, thirst, cramps or weakness can be warning signs. Follow NHS advice and get urgent help for possible heatstroke.

Related guides

How to cool a room without air conditioning →How to use a fan effectively →How fans cool you →Why opening windows can make your room hotter →

Sources & evidence

Reviewed 2026-08-21

  1. UK Health Security Agency: Beat the heat: keep cool at home checklist ↗

    Supports: Window timing, shading, ventilation, reducing internal heat and identifying higher-risk homes.

    official guidance · Accessed 2026-08-21

  2. NHS: Heat exhaustion and heatstroke ↗

    Supports: Symptoms, first response, NHS 111 advice and emergency action.

    health guidance · Accessed 2026-08-21