Transient modeling of high-inertial thermal bridges in buildings using the equivalent thermal wall method

The method of the equivalent thermal wall has been employed for modeling the transient response of high-inertial thermal bridges. A new strategy is presented in order to adjust the thermal properties of the equivalent three-layered wall, which takes into account the temperature distribution across the thermal bridge in a steady-state heat conduction scenario. Two different thermal bridge topologies created by the junction of a vertical wall and an intermediate or a ground floor slab are analyzed with this method, and its feasibility for the implementation in building energy simulation tools is discussed: if the thermal bridge is not considered, an underestimation of 25% in the heat flux across the bridge is predicted. If the thermal bridge is modeled but its thermal inertia is neglected, a time-delayed heat flux response is retrieved. Conversely, the simulation based on the equivalent wall method provides a response nearly identical to the actual dynamic performance of the thermal bridge. [Display omitted] •Two highly-inertial thermal bridges are analyzed using the equivalent thermal wall method.•We present a method for obtaining the thermal properties of the equivalent walls.•A strategy for the decomposition of the thermal bridges into several walls is devised.•The transient performance of the equivalent thermal walls is compared with classical models.•A reliable analysis of the transient thermal performance through thermal bridges is demonstrated.