Wärmestege

Wärmestege, often translated as "heat bridges" or "thermal bridges," are localized areas within a building envelope that have a significantly higher thermal conductivity than the surrounding materials. These are points where heat can more easily transfer from the interior to the exterior in winter, and from the exterior to the interior in summer. Common examples include structural elements like concrete beams that extend through insulation layers, metal studs in walls, or even poorly installed window frames.

The presence of Wärmestege leads to several undesirable consequences. Firstly, they reduce the overall thermal performance of the building, resulting in increased energy consumption for heating and cooling. This is because more energy is required to maintain a comfortable indoor temperature when heat is escaping or entering through these weak points. Secondly, Wärmestege can cause discomfort for occupants due to cold spots near them in winter, or hot spots in summer. Critically, they can also lead to condensation problems. When warm, moist indoor air comes into contact with a cold surface on the interior side of a Wärmestege, it can cool below its dew point, causing water vapor to condense. This condensation can lead to mold growth, material degradation, and a deterioration of indoor air quality.

Preventing and mitigating Wärmestege is a crucial aspect of energy-efficient building design and construction. Careful planning, material selection, and meticulous installation are essential. Techniques such as continuous insulation layers, thermal breaks in structural components, and the use of low-conductivity materials at potential bridging points are employed to minimize heat loss and condensation risks. Building codes and energy performance standards often specify requirements to limit the impact of Wärmestege.