Enhanced Fujita scale damage indicators and degrees of damage, chapter 20
Institutional Buildings (IB)
Typical Construction:
- Examples are hospitals, courthouses, university buildings, state and federal buildings, jails
- Range in height from 1 to 10 storeys; balconies, porches and porticos with heavy façade
- Roofing materials include fully adhered and mechanically fastened single-ply membranes, polyurethane foam, and copper-clad domes
- Structure is normally reinforced concrete, relatively small windows
- Walls are masonry with cut stone or pre-cast panels - may be very ornate
| DOD | Damage Description | EXP* | LB* | UB* |
|---|---|---|---|---|
| 1 | Threshold of visible damage | 115 | 95 | 140 |
| 2 | Loss of roof covering (up to 20%) | 140 | 115 | 175 |
| 3 | Damage to penthouse roof and walls; loss of rooftop HVAC equipment | 150 | 120 | 180 |
| 4 | Broken glass in windows or doors | 155 | 125 | 185 |
| 5 | Uplift of lightweight roof deck and insulation; significant loss of roofing material (more than 20%) | 185 | 155 | 220 |
| 6 | Façade components torn from structure | 190 | 155 | 225 |
| 7 | Damage curtain walls or other wall cladding | 210 | 175 | 245 |
| 8 | Uplift of pre-cast concrete roof slabs | 230 | 190 | 260 |
| 9 | Uplift of metal deck with concrete fill slab | 235 | 190 | 275 |
| 10 | Collapse of some top story exterior walls | 240 | 205 | 275 |
| 11 | Complete destruction of all or a large portion of building | 340 | 285 | 430 |
*All wind speeds in km/h