Enhanced Fujita Scale Damage Indicators and Degrees of Damage

Low-Rise Buildings: 1-4 Storeys (LRB)

Typical Construction:

Generally consist of rectangular modules but can be “odd shaped” in plan
Most will have flat roofs but can have gable, hip or mansard shapes
Roofing materials include BUR, single-ply membrane, metal panels or standing seam
Roof deck is wood or metal deck, poured gypsum deck or concrete slab
Steel or reinforced concrete structural frame
Glass and metal curtain walls, metal studs with EIFS, non-bearing masonry walls with stucco or brick veneer
Examples are office buildings, medical facilities, and bank buildings

Notes:

Table 17. Degree of Damage (DOD) for Expected (EXP), Lower Bound (LB) and Upper Bound (UB)
DOD	Damage Description	EXP*	LB*	UB*
1	Threshold of visible damage	109	89	134
2	Loss of roof covering (less than 20%)	129	108	166
3	Uplift of metal roof decking at eaves and roof corners: significant loss of roofing material (20% or more)	163	134	193
4	Broken glass in windows, entryways or atriums	163	134	196
5	Uplift of lightweight roof structure	214	183	253
6	Significant damage to exterior walls and some interior walls	230	196	269
7	Complete destruction of all or a large section of building	303	259	356

*All wind speeds in km/h

Page 17