What indicates substantial structural damage to a building?

Substantial structural damage to a building is indicated by the measurements of vertical elements suffering damage. Vertical elements, such as columns, beams, and load-bearing walls, play essential roles in supporting the weight of the structure and resisting forces such as wind and seismic activity. When these elements are compromised, the structural integrity of the entire building can be at risk. This can lead to potential hazards, including collapse or severe deformation, making it critical to assess the condition of these elements when evaluating structural damage.

In assessing damage, while aesthetic changes or the destruction of non-load bearing walls can certainly impact the overall appearance and functionality of a building, they do not suggest substantial issues regarding its structural stability. Repairs costing over 30% of the total structure value can be indicative of significant problems, but without context regarding the nature of the damage (especially relating to vertical support), this threshold doesn't inherently define structural failure. Thus, the most precise indicator of substantial structural damage is indeed observable damage to vertical elements.