Lambda value

The heat conductivity of a material is known as its lambda value. The lambda value is used for thermal calculations on buildings and thermal components.

The Greek letter λ, lambda, [W/mK] is used to represent the heat conductivity of a material. The heat conductivity of a material is thus popularly known as its lambda value. The lambda value is used for thermal calculations on buildings and thermal components (insulation, etc.). The thermal conductivity of a material is defined as the quantity of heat transferred in a given time through a distance L in a direction normal to a surface area A, due to a temperature difference ΔT, and when the heat transfer is dependent only on the temperature gradient. Thus, the lower a material’s lambda value, the better its ability to insulate.

Used for these calculations on buildings and thermal components, the Lambda value is relevant for heating applications in domestic and commercial buildings.