Which property is used to describe heat transfer resistance in insulation performance?

• A. K-Factor
• B. Density
• C. Color
• D. Opacity

Answer: (A)

Heat transfer through a material is governed by how easily heat can move through it, which is described by its thermal conductivity. The K-Factor (k-value) represents this property, showing how readily heat flows per unit thickness and temperature difference. The goal of insulation is to resist heat flow, so a lower k-value means higher resistance and better insulation performance. Density, color, and opacity don’t directly describe how heat transfers through a material, so they’re not used to characterize insulation resistance.