About Thermal Bridge Supplements

Thermal bridges are thermal weak points in the building envelope that lead to increased heat loss. To ensure that the additional heat losses at the building components are taken into account in the calculation, two different methods are available for assigning thermal bridge supplements to these building components, the global and the detailed thermal bridge supplement.

Global thermal bridge supplements

In the case of global thermal bridge supplements, you define the supplements for components that are adjacent to the ground, the outside or an unheated room using the thermal bridge supplements stored in the master tables. If necessary, you can edit the thermal bridge supplements in the master tables and add values.

Detailed thermal bridge supplements

With detailed thermal bridge supplements, you can assign length- and point-related heat transmission coefficients to the components that are adjacent to the outside or to an unheated room in order to consider the thermal bridges in detail in the calculation.

Length-related thermal bridge supplements are to be used for linear thermal bridges. Linear thermal bridges are disturbances that can be related to a length (e.g. balcony connections, edges of flat roofs, etc.). The Psi value used corresponds to the additional energy loss of a length-related disturbance measuring one meter at a temperature difference between indoor and outdoor air of 1 °C. The physical unit of the length-related heat transfer coefficient is watts per meter and kelvin (W/(m*K)).

Point-related thermal bridge supplements shall be used for punctual thermal bridges. Punctual thermal bridges are disturbances that must be referenced to a point. The Xi value used corresponds to the additional energy loss of a disturbance at a temperature difference between indoor and outdoor air of 1 °C. The physical unit of the point-related heat transmission coefficient is watts per Kelvin (W/K).

For detailed thermal bridge supplements, a horizontal, vertical or punctual thermal bridge supplement is first assigned to the component. The dimensions for the supplement are taken from the component (TBS horizontal: width, TBS vertical: Height). In the next step, the thermal bridge supplement is assigned a standard-compliant, self-created variable from the variable table for Psi values. By assigning another Psi or Xi value, you can correct the assigned variable of the thermal bridge supplements without adjusting the variable used. Such corrections allow you to reduce the number of additional variables to be created.

In the master tables, you can directly edit the Psi and Xi variables table to create all the required supplements with the corresponding values for your project. In addition, you can use a factor in the table to specify how the heat losses of the thermal bridge are accounted for.

Thermal bridge supplements for window components

For window components, the heat losses between the wall and the window in the lintel, reveal and parapet can be defined with corresponding values. These thermal bridge supplements are then taken into account when calculating the heat loss of the window.