Extreme weather events like hurricanes, tornadoes, and wildfires constantly remind multifamily owners and operators—and the insurance partners they work with—about the growing necessity of resilient construction.
Despite ever-stringent building code, efforts to limit damage fall short, leaving many to wonder, “How many times do we have to repeat this?”
The good news is the answer isn’t far from where Hurricane Helene made landfall in late September.
It’s called the Sand Palace, a seven-year-old beachside residence in nearby Mexico Beach, Florida.
You may be familiar with the property: The structure inspired a torrent of online memes in late 2018 after surviving a direct hit from Category 5 Hurricane Michael. Winds over 160 mph and tidal surges annihilated neighboring structures, while the Sand Palace appeared largely untouched. Iconic aerial photos of the building surrounded by blocks of sheared-off desolation remain chilling and haunting to this day.
Was the Sand Palace a lucky, one-in-a-million miracle? The architect and owners know better. Nearly everything about the construction anticipated “the big one.”
8 Resilience Lessons
What lessons does that example offer own-and-hold multifamily developers and owners? What ideas could help mitigate your operational risk in extreme weather zones? Forensic construction professionals identify at least eight decisions the architect, general contractor and owner made to hurricane-proof this investment:
1. The building sits atop 40-foot-long precast, pre-stressed concrete piles driven 28 feet deep, well beyond code requirements.
2. Steel cables lace the building from the girders above the pilings through the roof and continue down the back wall.
3. A proposed balcony on the east wall was removed as a precaution.
4. The roof overhang was kept very shallow compared with adjacent properties.
5. Some seaside windows were eliminated. Those that remained were engineered to withstand a Category 4 storm (and actually survived Category 5).
6. The building was built on stilts with sacrificial walls used on the ground floor, anticipating an aggressive tidal surge.
7. A simple hip roof minimizes wind uplift.
Yet it may be decision eight that helped shrug off Michael’s fury as much as anything.
8. The exterior wall system is built entirely with insulated concrete forms (ICFs).
ICF is a highly evolved building system known for installation speed, energy efficiency, acoustic control, and, importantly, resilience. The system uses Lego-like EPS blocks laced vertically and horizontally with steel rebar to form a cast-in-place, continuously insulated concrete wall.
ICF envelopes are engineered to withstand wind speeds of 240 mph. Today, we know Hurricane Michael was not an anomaly. To the contrary, Category 4 and 5 hurricanes have become normalized, helping propel insurance costs sky-high, provided the insurance company will even consider the risk.
It’s true an ICF structure may be slightly more challenging to pencil out than a comparably sized stick-built structure. But once insurance and energy savings, resident-friendly acoustics, installation speed, and marketing differentiation (i.e., “Wouldn’t you rather live in a hurricane-proof apartment?”) are factored in, any difference likely favors ICF.
Few developers and owners will weigh all eight resiliency factors in investment calculations. However, running the central ones like ICF construction by insurance partners and investors may be a prudent long-term hold strategy for extreme weather zones.
Learn more about ICF resilience to extreme weather events like hurricanes, tornadoes, and wildfires.
