Which material property is important for determining energy efficiency in glazing?

The important material property for determining energy efficiency in glazing is thermal conductivity. This property measures how well a material can conduct heat. In the context of glazing, thermal conductivity directly affects the insulation performance of windows.

Lower thermal conductivity in glazing materials means that they are better at resisting heat flow, which helps in maintaining a building's internal temperature and reduces the need for heating and cooling. This enhanced energy efficiency is crucial for minimizing energy consumption and enhancing comfort within a building.

While factors such as density, flexural strength, and impact resistance might be important for other characteristics of glazing materials—like structural integrity and durability—they do not significantly influence energy efficiency. Therefore, thermal conductivity is the key property that directly impacts how materials manage thermal transfer, making it essential for energy-efficient design in windows and other glazing applications.