Wärmedurchgang

Wärmedurchgang refers to the overall heat transfer through a building component or a composite structure. It quantifies how much heat energy passes through a material or system per unit of time, area, and temperature difference. This concept is crucial in building physics and thermal engineering for assessing energy efficiency and comfort.

The Wärmedurchgang is primarily determined by the thermal properties of the materials involved and the geometric configuration of the component. It accounts for all modes of heat transfer: conduction, convection, and radiation. In a building context, it describes heat loss from a heated interior to the colder exterior during winter, or heat gain in the opposite direction during summer.

The key parameter used to express Wärmedurchgang is the U-value, also known as the overall heat transfer coefficient. The U-value is the reciprocal of the total thermal resistance (R-value) of a component. A lower U-value indicates better thermal insulation, meaning less heat is transferred, and thus higher energy efficiency. Conversely, a higher U-value signifies poorer insulation and greater heat transfer.

Calculating the Wärmedurchgang is essential for designing energy-efficient buildings, specifying appropriate insulation materials, and meeting building codes and standards related to thermal performance. It helps in predicting heating and cooling loads and in minimizing energy consumption for climate control.