Action first
Blackout curtains vs blinds vs external shading
Short answer
External shading usually stops the most solar heat. Curtains and blinds still help, especially when closed before sunlight reaches the glass.
How to choose
- ✓Use external shutters or awnings for strongest protection.
- ✓Use close-fitting lined curtains when external changes are not possible.
- ✓Choose blinds for adjustable light and glare control.
Why it works
This advice follows UK Health Security Agency guidance and the underlying principles of solar gain and shading.
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