Why it works

Why external shading works

Short answer

External shade blocks solar energy before the window and room absorb it, which is usually more effective than dealing with the heat indoors.

The simple explanation

  • Awnings can shade high summer sun.
  • Shutters provide strong protection.
  • Trees and planting can provide seasonal shade where appropriate.

Why it works

This advice follows UK Health Security Agency guidance and the underlying principles of shading and solar gain.

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

  1. 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