Openings tab in model data under External Glazing, Internal Glazing and Roof Glazing headers
You can select two types of shading for external windows under the Shading header on the Openings tab:
These types of shading can be used individually or combined.
Other shading mechanisms supported by DesignBuilder are:
Window and Local shading are both covered in the Shading via louvres, overhangs, and side fins tutorial