Conduction is defined as the process of heat transfer through a material. This occurs when heat energy is transferred from the hotter part of a material to a cooler part, primarily due to direct contact between particles. In solids, especially metals, conduction is particularly efficient because the tightly packed particles are able to transfer energy quickly and effectively.
In practical terms, when discussing roofing or building materials, understanding conduction is crucial for assessing how heat may move through a roof assembly. For example, a metal roof might conduct heat differently than an asphalt shingle roof, impacting the overall energy efficiency of a building.
The other options relate to differing processes: air-based heat transfer refers to convection, the conversion of gas to a liquid depicts a phase change rather than conduction, and filtration pertains to air purifying processes that don't involve heat transfer. Understanding these distinctions helps clarify the concept of conduction within the broader context of thermal dynamics in roofing systems.