Home Inspection State Practice Exam

Fiberglass batt insulation slows heat movement primarily by slowing air movement within the insulation. The structure of fiberglass insulation contains numerous tiny air pockets, which act as barriers to heat flow. When air movement is constrained, there is less convective heat transfer, meaning that warm air does not circulate as easily through the insulation. This characteristic is what makes fiberglass effective at insulating a space; it reduces thermal bridging and conserves energy by preventing heat from escaping or entering a home.

The other choices do not accurately describe the key function of fiberglass batt insulation. Increasing air temperature doesn't directly relate to insulation performance; instead, insulation works by reducing heat loss irrespective of air temperature. Enhancing thermal conductivity contradicts the purpose of insulation, which is to have low thermal conductivity to reduce heat flow. Retaining moisture may lead to reduced insulation efficiency and potential growth of mold, but it is not a mechanism through which insulation achieves its purpose of slowing heat transfer.