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A couple living in Hawaii received a letter notifying them that their hurricane insurance policy would be dropped—despite nearly 50 years of continuous coverage.
The reason?
When the Lyons originally built their Haleiwa home, they used single-wall construction, a design that was popular in the 1970s for its affordability and ventilation-friendly layout. Now, it’s considered structurally inferior in hurricane-prone areas. Since then, they’ve made no improvements to the home—and now it’s about to cost them.
This is one example of how outdated building styles can lead to unexpected financial consequences, especially in a time when insurers are increasingly pulling out of high-risk zones.
What is single-wall construction—and how does it differ from double-wall or concrete?
Single-wall construction, often found in older Hawaiian homes, uses individual wood panels as both the interior and exterior walls, eliminating the need for separate framing, insulation, or drywall.
The exterior walls are typically built with redwood, which is what the Lyons have, or other rot-resistant wood.
Single-wall construction was once popular in Hawaii due to the tropical climate, as insulation and heating weren’t necessary. These homes were cheaper and faster to build, but offered little soundproofing and were more vulnerable to high winds.
By the late 1980s, single-wall construction began to fall out of favor as building codes evolved and energy efficiency became a higher priority.
Today, most homes use double-wall construction with insulation and interior walls—offering better energy efficiency and cooler interiors when using air-conditioning. Concrete homes are also on the rise for their durability and superior hurricane resistance.
“However, I’d say about half the homes we work on out here in Hawaii are still single-wall construction,” says homebuilder Richie Breaux, founder of All Things New Construction and author of “Builder of All Things.”
Why hurricane insurers are dropping homes with single-wall construction
Hurricane insurance is a separate policy from standard homeowners coverage in many coastal and island states. It’s becoming harder to secure as storms increase in frequency and strength.
In this case, the insurance company viewed single-wall construction as too high-risk—offering little resistance to wind uplift or flying debris. That’s especially critical in hurricane-prone regions like Hawaii, which has seen an uptick in climate-related risk modeling.
“Insurers themselves are reassessing their risk ever since the Lahaina wildfires,” Hawaii’s acting Insurance Commissioner Jerry Bump explains.
But all across the country, insurers are now reassessing legacy policies based on that new construction risk data.
“Homeowners with old, or out-of-code, structures are generally first in line to get dropped,” says Jordan Blake, director of communications and operations at Shoreline Public Adjusters, a firm that represents policyholders in claims involving nonrenewals. “It’s not always about a history of claims, or whether a home is in Tornado Alley. More and more, it’s about how a home is constructed and how it’s expected to perform when subjected to stresses.”
Some policies might be nonrenewed with little recourse other than making costly upgrades or switching to state-backed insurers if available.
This kind of reevaluation is becoming more common—not just in Hawaii, but across wildfire- and storm-prone areas in states such as Florida, California, and Louisiana.
“Increased risk and high claim costs are causing insurance companies to pull back or stop writing policies entirely in certain areas,” says Leslie Kasperowicz, executive editor of Insurance.com.
And data shows more homebuyers in high-risk areas are forgoing insurance altogether for cost reasons, according to Max Dugan-Knight, a climate data scientist at Deep Sky, a carbon removal project developer working to reverse climate change. “That is a very dangerous proposition.”
What does it cost to upgrade—and is it worth it?
If your insurance gets dropped, “the most actionable thing you can do is to make sure that your home is resilient enough to reduce risks and make it more insurable,” says Alex Adekola, CEO and founder of ReadyAdjuster. “Adapting your home to climate change is key.”
More homeowners are doing just that.
“Pretty much every home we touch now, we’re upgrading from single- to double-wall construction, especially on the exterior,” says Breaux.
But it’s not cheap.
The renovation costs associated with upgrading a home from single-wall to double-wall average $100 to $125 per square foot, according to Breaux.
“It adds up, but it’s a massive upgrade for the home,” he says. “We keep the single-wall structure in place and build the double wall on the interior.”
The process often includes wrapping the outside for weatherproofing, adding insulation for thermal protection, and finishing it off with new exterior siding.
A renovation like this typically takes three months, but it can take much longer to secure permits.
“In some cases, I’ve seen it take 16 months or more just to get the green light to start,” warns Breaux.
If you want to mitigate risk without taking on a full reconstruction, you can always explore targeted reinforcements.
Breaux recommends adding hurricane clips, which can range from a few thousand dollars to $5,000.
Hurricane shutters and straps are also a viable option.
Hurricane shutters run an average of $3,700—while the price to install hurricane straps on an average-sized home is typically $1,000 to $1,500.
Homeowners should have their home evaluated by a structural engineer and get multiple quotes before agreeing to a rebuild.
“Get at least three solid bids from licensed contractors before you start,” advises Breaux.
When funds are limited, choosing a bare-bones policy from a provider like the FAIR Plan might be the more practical route than reconstruction.