In order to allow for the shading effect of surrounding objects, enter the Average Height and Average Distance that the Facade is from any large object facing your selected Façade.
Note: The Surrounding Buildings feature will only display when an entire Façade is selected. When a single Surface or only a few Surfaces are chosen, this feature will not be available since a shading object cannot affect only a single Surface or Surfaces on different orientations to the same extent.
Facades/Surfaces may also have the same orientation but exist on different planes and so would be affected to different extents. This feature, to simulate surrounding objects that would cause a shading effect on the model, currently only affects the Daylighting results and not the Solar Loads.