Which barrier provides resistance to heat loss by conduction and creates a thermal resistance layer (R-value)?

• A. Air Barrier
• B. Thermal Barrier
• C. Moisture barrier
• D. Weather/Wind Barrier

Answer: (B)

The idea here is that heat flowing through a material layer is slowed by a barrier that provides thermal resistance. That layer is the insulation, referred to as a thermal barrier, which creates an R-value. In other words, R-value measures how well a material resists heat transfer by conduction, and the thermal barrier is the component that establishes that resistance. An air barrier focuses on stopping air leakage (reducing convective heat loss), a moisture barrier blocks moisture movement, and a weather/wind barrier reduces wind effects—none set up the conductive resistance the way insulation does. So the best fit is the thermal barrier.