A. Christopher DeBlois, a structural engineer with Palmer Engineering in Tucker, Ga., responds: Why not add a shallow soffit around the perimeter of the room to create the same effect? If there’s enough ceiling height, the loss of 4 to 6 inches of headroom around the edge may not be objectionable, and this approach has no structural implications for the trusses.
If that solution is not acceptable, it might be possible to cut out the bottom chord of the truss and add collar ties. But unless you know how to design trusses, you’ll need an engineer to help you. There are a few key issues.
to read the full article.