Check the building plans or structural drawings
Look for walls that run perpendicular to floor joists above
Look for walls directly beneath beams, columns, or load-bearing walls on upper floors
Check for walls aligned with foundation walls or support posts below
Inspect for thicker walls than surrounding partitions
Look for walls made of masonry, concrete, or reinforced materials
Check for walls that continue through multiple floors in the same location
Look for walls near the center of the building that support spans
Inspect for joist direction in the attic, basement, or crawl space
Verify with a structural engineer or qualified contractor before removing or altering any wall