Kopplung von dynamischer Wärmebrückenberechnung mit hygrothermischer Gebäudesimulation

Coupling of dynamic thermal bridge and hygrothermal building simulation.

With increasing requirements on the thermal envelope of buildings dynamic building simulation is used more and more often for the design. Contrary to balance methods thermal bridges are often not accounted for in dynamic simulation. Especially the combination of a hygrothermal building simulation with the simulation of thermal bridges would allow assessing the dynamic influence of thermal bridges on the building energy demand, but also allow analyzing a possible risk for mould growth.
This article presents the simulation methods for hygrothermal whole building simulation and thermal bridge simulation as well as their coupling. After validation of the thermal bridge module, which ensures a standard-conform implementation, an exemplary application case for the new simulation software is shown. Mould growth is sometimes found in the non-insulated and before damage free apartment, in cases where one of two side-by-side apartments is retrofitted with interior insulation. It is shown, how the temperature distribution in the exterior wall is changed due to the partial interior insulation measure. The influence of room temperature, moisture production, room ventilation and insulation thickness on the relative humidity on the coldest spot in the corner is analyzed. The partial retrofit causes higher and sometimes critical moisture conditions on the connection between exterior wall and party wall.
In summary a hygrothermal whole building simulation software with coupled three dimensional dynamic thermal bridge simulation is presented. The thermal bridge module is successfully validated and the combined software applied to a practical case.