Building codes can play a crucial role in enhancing communities’ resilience to severe weather events. Andrew MacFarlane at 色多多视频explains the importance of having robust and stringently-applied codes, and why insurers and reinsurers should work to support the development and implementation of standards and codes that will help to better protect communities from catastrophic damage – and improve their resilience.
Insurers and reinsurers may be breathing a sigh of relief that despite being the fourth most active year on record, the 2023 Atlantic hurricane season saw just three storms make landfall in the United States. But with 20 named storms – well above the annual average of 14 – the 2023 season underlines the effects that a changing climate is having on potential insured and reinsured exposures – the world over.
Of the 20 named storms in 2023, seven were hurricanes and three were major hurricanes, according to the National Oceanic & Atmospheric Administration (NOAA), above the usual number. And while not all of these storms made landfall in the United States, those that did – Hurricanes Harold, Idahlia and Ophelia – resulted in damage to homes and businesses and, tragically, loss of life.
The insurance and reinsurance community is eager to find ways to support efforts to build resilience to hurricanes and other severe weather events that occur year-round across the world. The adoption and application of building codes, setting out minimum measures to which buildings must adhere to protect them, is one way of boosting resilience.
Building Codes can help structures to better withstand the effects of severe weather events, and it is in the interests not only of home and building owners, but also the insurers and reinsurers that bear some of the risk, that these codes are well researched and correctly applied.
Lessons learned from Hurricane Ian
Hurricane Ian in 2022 caused widespread damage to parts of Florida and provides an interesting example of how modern building codes can improve resilience to weather events. Florida is particularly vulnerable to North Atlantic hurricane activity and is widely regarded as having the most stringent state-wide building code in the United States.
According to the NOAA, Hurricane Ian caused about $112.9 billion in damage when it made landfall along the barrier island of Cayo Costa, near Punta Gorda, Florida, in September 2022. A category 4 storm, Hurricane Ian made landfall in almost the exact same area as Hurricane Charley in 2004. It was the first major test of the efficacy and application of the 2002 modern Florida building code since that devastating storm, which formed part of a series of major storms in 2004.
Hurricane Ian caused catastrophic storm surge, with a peak inundation of about 15 feet. And post-event analysis suggested that there were peak wind gusts of between 150 m.p.h. and 160 m.p.h., just below the design-level wind as per the 2002 Florida building code.
The area affected by Hurricane Ian contained diverse building stock of various ages and construction type, giving researchers valuable insights into how different buildings performed during a category 4 hurricane and how effectively building code provisions had been applied.
Recent research by the non-profit 色多多视频 Institute for Business & Home Safety (IBHS), found that, typically, those homes built after 2002 suffered far less damage than those built before that date.
The effect of the storm on the roofs of buildings – sometimes referred to as the first line of defence - can give a snapshot into how well the building code safeguarded different structures against severe damage.
Many of the homes and small commercial buildings in the area hit by Hurricane Ian had roofs that had been replaced or repaired in the aftermath of Hurricane Charley some 18 years previously.
Analysis from IBHS of the way roofs withstood Hurricane Ian shows that different types of roofing performed quite differently and that the extent and effectiveness of how the 2002 Florida building code had been applied often had an effect on the level of the damage and loss.
For example, most of the residential roof damage caused by Hurricane Ian was to asphalt shingle roofs. IBHS analysis found that one in every two asphalt shingle roofs it assessed had detectable damage caused by the storm. And those damage rates were broadly similar to those observed after Hurricane Charley.
IBHS observed that, during Hurricane Ian, if an asphalt shingle roof was 10 years old or older, the probability of damage in maximum level gusts of 110 m.p.h. or more was greater than 75%.
In the areas affected by Hurricane Ian, asphalt shingles regularly failed at a lower rate frequency than a 1-in-50-year return interval event – far less than the 1-in-700-year windstorm which modern-code-bult homes are designed to withstand.
In the case of low-slope, light commercial membrane and built-up roofs, the damage rate was also above 50%, the IBHS found. And of the low-slope roofs with visible damage, 71% had visible damage to flashing and/or coping. This suggests that the provision for flashing and coping added to the Florida building code in 2004, which went into force in 2005, were perhaps not adequately, effectively or uniformly being applied.
The performance of steep-slope metal roofs was generally good, the IBHS noted, and where there was damage, it had often been caused by the failure of another building element, like a car-port. And this was particularly noticeable on homes built before the building code was widely implemented in 2002.
Tiles roofs, the IBHS found, experienced damage rates of slightly above 40%, a vast improvement compared with damage after Hurricane Charley. This reduced severity of damage likely reflected both improvements made by tile manufacturers and the implementation of building code provisions regarding the fastening of tile roof systems, according to the IBHS.
Why building codes matter
The research carried out by IBHS in the wake of Hurricane Ian appears to suggest that where building code requirements are implemented effectively, resilience to severe weather is – sometimes greatly – enhanced.
There is, however, a large amount of work to be done – around the world – to improve building codes in general. Insurers and reinsurers have an interest in helping to make this happen. As well as the clear societal benefits to ensuring that homes and places of work are more resilient to damage, codes that help to make buildings more resilient to severe weather events should also have the effect of improving the risk that insurers and reinsurers take on – or stem the worsening of the risk given the changing nature of the threat.
Our climate is changing, and severe weather event patterns are in flux. The frequency and severity of extreme weather events is increasing exposures for many areas meaning more buildings are at risk from severe weather effects like wind or flood damage.
Vulnerable communities too, that are less likely to be covered by commercial insurance policies, could see enormous benefits from the introduction of minimum standards and codes for buildings. This, in turn, again improves the risk for potential insurers and reinsurers to consider and may help to reduce the so-called protection gap.
Enhancing resilience to severe weather is a common goal for individuals, communities, governments and insurers and reinsurers. Buildings codes can play an important part in improving resilience and we will support their development and adoption as we all seek to adapt to the effects of a changing climate.
