Recurrent wildfires in California are exposing a mismatch between how homes are built and the conditions they now face.
Communities must rebuild after repeated losses while navigating stricter codes, slower permitting, higher insurance costs and the possibility that the next fire arrives before recovery is complete.
One response has come from S.A.M. House, a panel-based system developed by registered architect Gary Hendren.
It uses glass fiber reinforced concrete panels as structure, exterior skin and roof, aiming to deliver rapid assembly, fire resistance and durability against wind and flooding.
Drawing on five decades of work in hurricane-prone regions from Miami to the Caribbean, Hendren designed the system for large-scale post-wildfire rebuilding.
FSJA sat down with Gary Hendren to learn how the system works for future rebuilding.
The original impetus for the S.A.M. panel house came after a Category 5 hurricane struck Great Abaco Island in the Bahamas, flattening much of the local workforce housing.
I began sketching a simple panelized system that could be assembled with minimal skill, rebuilt quickly after disasters and remain affordable.
Drawing from my experience with a wide range of materials, I identified glass fiber reinforced concrete as having strong potential at a residential scale.
GFRC is lightweight, waterproof, low-maintenance, durable and easily molded into panels.
Traditionally it is clipped onto a steel frame, but I wanted the panels themselves to function as both the structure and the exterior skin.
Working closely with structural engineers and materials laboratories, we designed panels capable of resisting hurricane winds up to 200 mph.
During this process, we recognized that the panels were also inherently fire-resistant, which led us to expand testing to include fire exposure and seismic performance for California applications.
The fundamental difference between a S.A.M. House and a conventional wood-framed home is simple: a S.A.M. House does not burn.
Visually, however, it looks like a conventional residence.
The system is modular and flexible, allowing it to accommodate a wide range of floor plans.
GFRC is highly moldable and can replicate brick, stone or wood shingles.
Panels are fabricated in a factory and assembled on site, reducing construction time and material waste.
Because the roof is also made from GFRC panels, there is no conventional roofing membrane that must be replaced every 15 to 20 years.
The panel system has been engineered and wind-tunnel tested to withstand wind speeds of up to 200 mph.
Because S.A.M. House panels do not absorb water, flood exposure does not require demolition of wall assemblies, insulation replacement or structural repairs, issues commonly associated with wood-framed construction and mold development.
Both the walls and roof are constructed from the same lightweight concrete panel system, which does not burn or contribute fuel to a wildfire.
We have also identified fire-rated window systems using steel frames and ceramic glass. Exterior doors are commercial-grade fire-rated steel assemblies, so there are no combustible exterior components that can ignite or exacerbate fire spread.
The panels do not burn. The material is synthetic concrete which is non-flammable.
We piled a stack of wood against it and lit it on fire with lighter fluid and the panel did not ignite.
The University of Miami Materials lab then sent a panel to a fire testing facility where it was subjected to 1000 degrees of gas flames for two hours, giving it a certified two-hour fire rating.
The compressive strength of the concrete was retested and showed only a three percent loss of strength after the fire exposure.
I would expect the real-world impact on the panel to be less stressful than the lab testing, as the temperature of a passing wildfire will start at around 500 degrees and only last for 15 to 20 minutes as long as there are no materials on or next to the house that will fuel the fire.
As S.A.M. Houses do not need siding or roofing materials, there is no additional fuel for the fire.
If a fire starts on the interior, the interior finish of the walls and ceiling are also fire-proof resilient cement panels rather than sheetrock, which are non-flammable and waterproof.
Even if the fire department sprays water throughout the house, the interior finish will not have to be removed and replaced.
The insulation inside the walls is mineral wool which is also non-flammable and does not absorb water so it does not need to be replaced.
The S.A.M. House was conceived as a disaster-replacement housing system. It combines strength, durability and fire resistance with rapid construction.
Because the panels are factory-fabricated, production is not weather-dependent and on-site assembly takes a fraction of the time required for conventional construction.
Panels are stained in the factory, removing the need for initial field painting or ongoing repainting.
If a panel is damaged during a storm, it can be replaced because the panels are bolted together with a fire-rated gasket between them.
In a finished house, that requires removal of the interior wallboard panels to access the bolts, replace the damaged panel and reinstall the insulation and interior finish panel.
Currently, the S.A.M. panel system is roughly 10 to 15 percent more expensive than traditional wood frame construction. As the system becomes a standard for the industry and panels are fabricated in bulk, we expect the cost to come down.
In the long term the S.A.M. is a smarter investment as it survives a wildfire and does not have to be torn down and replaced.
The panels are stained in the factory and never have to be repainted. There are no roofing materials required that must be maintained or replaced every 15 to 20 years even if no disasters occur.
The panels are fabricated from a mold, must cure for 14 days before shipping and must finish curing for an additional 14 days before being erected.
The rate of fabrication is dependent on the number of molds available.
We currently have three fabrication locations and redundant molds and stored common panels.
If a major disaster occurred, all the regional fabrication plants could be dedicated to ship panels to the impacted area.
Depending on the scale of the disaster, additional molds usually take six to eight weeks to be fabricated and placed into production.
I have had discussions with insurance companies and sent them our testing data.
The risk management department is impressed with the properties of our panels for sustainability and durability and are open to providing insurance policies at reasonable cost depending on the exact location of the home.
Currently, the S.A.M. panel system is not explicitly defined within building codes, as it synthesizes multiple code provisions into a single integrated system.
Innovative construction methods require extensive testing and evaluation.
We have worked with premiere structural engineers and certified testing laboratories to design the S.A.M. panels and are currently completing the International Code Council Evaluation Summary Report.
The primary challenge in adoption is unfamiliarity.
While builders, developers and homeowners often agree that the system makes sense, many are reluctant to be the first to use a new technology.
Regulatory agencies face similar concerns.
Despite passing 34 separate performance tests, the system represents a departure from conventional construction and officials are understandably cautious.
Insurance companies tend to be more receptive, as their risk management teams are accustomed to performance-based evaluation.
Traditional wood-frame housing is increasingly inadequate in the face of wildfires, floods, hurricanes and tornadoes.
The technology exists today to build homes capable of lasting well into the future.
