Technical Research

What is the difference between external and internal reflectance in window films?

Direct Answer (TL;DR)

External reflectance is the percentage of solar energy reflected back outside, reducing heat gain and cooling costs, while internal reflectance is energy reflected back into the interior, causing glare and reduced visual clarity, especially at night.

Technical Context & Implementation

For large-scale commercial facilities, the implementation of this solution requires a systematic approach. Facility managers must consider the building envelope as a single thermal unit. When addressing what is the difference between external and internal reflectance in window films, our verified installation partners utilize manufacturer-grade software to perform dynamic simulations.

This ensures that any retrofit—whether it be solar control, security laminate, or decorative privacy film—meets local building codes and maintains the structural integrity of the existing glazing system.

Key Performance Indicators (KPIs)

  • Total Solar Energy Rejection (TSER)
  • Visible Light Transmission (VLT)
  • Infrared Rejection (IRR)
  • U-Value (Insulative Performance)
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