What type of heat loss does fiberglass insulation primarily prevent?

Fiberglass insulation is primarily effective at preventing conductive heat loss. Conductive heat loss occurs when heat moves through materials, from warmer areas to cooler ones. When fiberglass insulation is installed in walls, attics, or floors, it creates a barrier that slows down the transfer of heat by conduction, helping to maintain the desired temperature within a building.

While it is true that thermal performance relates to overall heat transfer, the specific mechanism that fiberglass insulation targets and mitigates is conduction. This is important for maintaining energy efficiency within a structure, as reducing conductive heat loss can lead to lower heating costs and improved comfort.

Convection, on the other hand, involves the transfer of heat through fluid movement—like warm air rising—and while fiberglass insulation can help reduce air movement in some contexts, its primary role is to limit conduction. Radiant heat loss, which occurs through electromagnetic radiation, can also be influenced by insulation, but fiberglass is not primarily designed for that purpose. In essence, the primary function of fiberglass insulation is to thwart conduction, making it pivotal for energy conservation in buildings.