KC Wind Damage Scale ™

KC Scale Damage Wind speed Damage Description
KC 0
None Under 40 mph No insured damage expected.
 
KC 1
Slight 40-60 mph Slight damage, barely visible. Few shingles off some houses, tree limbs broken. Very little insured damage except from possible extensive inland flooding and heavy precipitation resulting in water damage and uprooted trees.
 
KC 2
Spotty 60-80 mph Spotty damage across affected area. Patches of shingles missing, minor roof covering, window and cladding damage to some wood frame, unreinforced masonry and light metal structures. Significant signage damage. Whole trees down causing some structural damage and power outages.
 
KC 3
Localized 80-100 mph Localized damage particularly to roofs of non-engineered buildings. Cladding damage to structures caused by wind effects and windborne debris. Contents damage from failed openings. Significant tree damage and localized power outages potentially lasting a number of weeks.
 
KC 4
Structural 100-120 mph Structural damage to non-engineered buildings, particularly wood frame and unreinforced masonry. Some low rise and light metal buildings can suffer complete collapse. Roof, cladding and contents damage to mid and high-rise commercial structures. Loss of rooftop equipment. Power outages over a widespread area causing general business disruption.
 
KC 5
Failure 120-140 mph Structural failure and many total losses on non-engineered buildings. Mid and high-rise structures begin to suffer significant roof and cladding damage. Significant wind and water infiltration damage to all types of commercial and industrial structures. Widespread power outages and economic disruption. Recovery and reconstruction efforts delayed by debris removal, labor and supply shortages.
 
KC 6
Extensive 140-160 mph Extensive destruction of non-engineered buildings including residential, commercial, and light industrial structures. Extensive roof, cladding, and contents damage to engineered buildings including high rises. Major infrastructure and power supply damage. Severe and long-lasting business interruption and additional living expenses.
 
KC 7
Complete 160+ mph Complete destruction except for the structural systems of low rise concrete block buildings, well built, engineered structures and high rises. Near total damage to building contents. Massive debris removal requirements. Recovery and reconstruction efforts severely hampered by infrastructure failures and obstructions. Some areas may take years or never fully recover.
Notes:
1. Non-engineered buildings typically include single and multi-family homes, small apartment buildings, motels, schools, small retail and professional buildings.
2. Structural damage means damage to major components of the building such as the roof or wall systems that compromises the structural integrity of the building.
3. Very light structures without foundations such as mobile homes, outbuildings, and pool enclosures can experience significant damage at wind speeds as low as 60 mph.
4. Tropical cyclones can spawn thunderstorm cells and tornadoes that cause insured damage far from the track of the storm.
 
    Summary  

KC 0
KC 1
KC 2
KC 3
KC 4
KC 5
KC 6
KC 7
None Slight Spotty Localized Structural Failure Extensive Complete
0-40 mph 40-60 mph 60-80 mph 80-100 mph 100-120 mph 120-140 mph 140-160 mph 160+ mph
 
 
KC Wind Damage Scale is a trademark of Karen Clark & Company © 2008. All rights reserved.