What does thermal bridging refer to in building construction?

Thermal bridging refers to a phenomenon in building construction where heat is conducted through materials that are less insulated than their surroundings, effectively bypassing the insulating layers meant to reduce heat loss. This occurs when there are breaks in the continuity of insulation, allowing heat to transfer directly through more conductive materials, such as metal or wood, which can lead to increased energy costs and discomfort within the building.

For instance, if a wall is properly insulated but has metal framing or other high-conductivity materials interrupting the insulation layer, those materials will conduct heat more effectively than the insulated areas, creating pathways for heat to escape during colder months or enter during warmer periods. Consequently, areas of thermal bridging lead to reduced overall energy efficiency, which is an important consideration in sustainable building design.

Understanding thermal bridging is crucial for building inspectors as it helps them assess potential energy loss in structures and suggests improvements for achieving better insulation and energy performance.