Action first
How to create cross-ventilation
Short answer
Give cooler air one safe opening to enter and warm air another opening to leave.
What to do
- ✓Open windows or doors on opposing sides.
- ✓Keep the path between them open.
- ✓Use smaller inlet and larger outlet openings if useful.
- ✓Only ventilate for cooling when outside is cooler.
Why it works
This advice follows UK Health Security Agency guidance and the underlying principles of cross-ventilation and airflow.
Important exceptions
Safety, health, weather and the design of your home can change what is appropriate. Stop if an action makes conditions worse.
Related guides
Sources & evidence
Reviewed 2026-08-21
- UK Health Security Agency: Beat the heat: keep cool at home checklist ↗
Supports: Shading, ventilation, reducing indoor heat and protecting people at higher risk.
official guidance · Accessed 2026-08-21