Enhanced Fujita scale damage indicators and degrees of damage, chapter 19
High-Rise Buildings: Greater than 20 Storeys (HRB)
Typical Construction:
- Generally consist of rectangular shapes but can have curved or triangle footprints
- Roofs are generally flat but may have a more complex roof shape as part of aesthetic statement; roofing material single-ply membrane fully adhered, polyurethane foam roof, metal or copper clad roof covering
- Structural frame is steel or reinforced concrete; penthouse is steel framing with metal panels
- Exterior cladding is glass or metal curtain walls or pre-cast concrete window panels
- First floor often has very large glass areas that are susceptible to debris impact
- Atriums with overhead glazing or tall window walls
- Examples are hotels, office buildings, and condominiums
| DOD | Damage Description | EXP* | LB* | UB* |
|---|---|---|---|---|
| 1 | Threshold of visible damage | 115 | 95 | 140 |
| 2 | Loss of roof covering (up to 20%) | 140 | 110 | 170 |
| 3 | Damage to penthouse roof and walls; loss of rooftop HVAC equipment | 150 | 120 | 180 |
| 4 | Broken glass in exterior walls at 1st and 2nd floors; broken glass in entryways | 165 | 135 | 195 |
| 5 | Damage to parapet walls or coping | 165 | 140 | 195 |
| 6 | Broken curtain wall panel anchors | 210 | 175 | 255 |
| 7 | Significant loss of roofing material (more than 20%) | 230 | 185 | 265 |
| 8 | Significant damage to curtain walls and interior walls | 235 | 200 | 275 |
| 9 | Uplift or collapse of roof structure | 255 | 200 | 295 |
| 10 | Permanent structural deformation | 365 | 305 | 465 |
*All wind speeds in km/h