Saipan resident Poima Maleah Mafnas Tarkong knew what to expect when Typhoon Bavi was approaching the Northern Mariana Islands. The 27-year-old had already been through three typhoons in her lifetime.
While her house is made of concrete, that didn’t stop rainwater from coming through her windows and flooding her home during Typhoon Sinlaku in mid-April.
“My husband and I didn’t sleep for two days because we kept shoveling water into the toilets, trying to salvage what we could of the house, and it was just really intense and stressful,” she said, referring to Typhoon Sinlaku.
Typhoon Bavi made landfall in the Mariana Islands on Monday morning (Sunday in Hawaiʻi), with the area still recovering from Super Typhoon Sinlaku. Bavi was estimated to be the largest storm at 1,029 miles wide. Officials have said there have been damages including downed power lines and trees and no deaths have been reported.
The National Weather Service has dubbed Sinlaku the world’s strongest storm so far this year, with destructive winds that displaced people from their homes and cut off power for tens of thousands and residents.
Powerful storms are common in the western part of the Pacific, but Typhoons Sinlaku and Bavi have unveiled disparities between those who can afford typhoon-proof homes and those who can’t.
Most homes built in the Commonwealth of the Northern Mariana Islands are made of concrete. But some still have wooden or tin roofs — not concrete roofs — because many residents cannot afford homes that are up to current building codes.
Mafnas Tarkong said that building fully concrete homes is expensive, given the region’s low minimum wage and high cost of imported materials. She said that upgrading a small one-bedroom home can cost at least $150,000.
“So many families here are struggling financially to make ends meet, and often they are living with their families, so building a fully concrete home is just not realistic," she said. “That’s how semi-concrete homes (concrete structures with tin roofs) or wood and tin homes become so popular. They’re more affordable.”
The CNMI adopted the International Building Code in 2018 and the International Residential Code in 2019, which governs the design and construction of one- and two-family dwellings. The codes were developed by the International Code Council, an American nonprofit that provides standards for the construction industry.
But in many island communities, affordability, material availability, labor resources and rebuilding after repeated storms can create challenges, according to Tim Waite, the senior territory manager of Simpson Strong-Tie, a company that makes materials to build hurricane and typhoon resistant homes.
As an engineer and building-products professional working throughout Hawaiʻi and the Pacific, Waite said one of the biggest factors affecting typhoon damage is not necessarily the choice of building material itself, but “how well the structure is designed, connected and constructed as a complete system.”
Guam has mostly reinforced-concrete residential homes, while in many parts of CNMI, it is more common to see concrete hollow-block homes with wood or steel roofs, according to Waite.
“These systems can perform well when properly engineered and detailed, but they rely heavily on adequate shear resistance (plywood), uplift connections (hurricane clips), and a continuous load path from the roof all the way to the foundation. Many of the hollow-block homes also lack a load path,” Waite said in an email to HPR.
He said that shutters are important because a home can be built in good condition, but if the windows and doors are compromised, then the pressure from the air can more easily damage roofs.
After back-to-back storms, Waite said he is hopeful there will be more effort to build stronger homes with government support. The priority, he said, is that damaged homes should be correctly rebuilt.
“Modern building codes and proper enforcement can significantly improve resilience, but even the best codes cannot eliminate damage when communities are exposed to some of the strongest storms on Earth, or especially if there is a lack of code enforcement and the structures are left vulnerable,” he said. “The goal is to help structures remain standing, protect occupants, hopefully built strong enough to shelter in place, and recover more quickly after the event. Education is key.”
