It may happen that surfaces are not connected, though they should be. In this respect, double lines may have an effect on the calculation. It is better to clean the model and remove all double lines.
You can find double lines quickly using the feature "Tools → Model Check → Overlapping Lines". This tool also allows you to export the line pairs as an Excel list or create partial views (see the highlighted buttons in Image 02).
However, it is often not easy to delete the lines, as they are assigned to different objects. Thus, if you delete one of the lines, you also delete a surface, for example. Therefore, you should first check all structural components to see whether the lines can be deleted, and change the boundary lines, if necessary. In the attached video, you can see how the boundary lines of the surfaces can be exchanged quickly. The remaining double line can then be deleted easily.
.png?mw=350&hash=1c031608c18b5a867799b52552d26586745de8ac)
.png?mw=600&hash=49b6a289915d28aa461360f7308b092631b1446e)
