Fire protection
Fire attacksthe whole window,not justthe glass
In most fire-hardened homes, the weakest openings are the windows and doors. Here's why they fail, what fire tests can and can't tell you, and what a window built for fire country really has to do.
The short answer
A window is only as strong as its weakest component. Glass, frame, thermal break, gaskets, seals and hardware all have to hold together when the fire arrives, because the moment one gives way, flame, embers, hot gases and fresh oxygen have a way into the house.
That's why Revyn protects the entire opening, not just the glass. The frame is welded 316 stainless steel, with no plastic holding it together. In CAL FIRE's eight-minute Wildland Fire Test, our window passed the minimum standard and kept performing unfazed until the lab turned the burner off.
Why it matters now
The fires aregetting bigger
19 OF 20
Of the twenty largest wildfires in California's recorded history, nineteen have happened since 2003.
5 OF 8
Five out of the eight largest fires burned in 2020 alone.
6,845
Structures destroyed by the Palisades Fire, which started on January 7, 2025.
9,419
Structures destroyed by the Eaton Fire, which started the same day.
Figures: CAL FIRE, as cited in Wide Open to Wildfire.
The book · Architect Edition
Wide opento wildfire
Are we playing with fire by overlooking windows and doors?
Written by the team behind Revyn, it explains what really happens when fire reaches a window, what today's tests do and don't tell you, and the questions to ask before you specify. Including the ones to ask us.
Read the opening chapters free, right here on our website.
Four assumptions
What most peopleget wrong aboutwindows in a fire
Our industry uses trusted words like tempered, steel, fire-rated, tested, passed or approved. Each term by itself doesn't tell you whether the entire window assembly was engineered to survive a wildfire.
01
"Windows fail because the glass breaks"
Glass fails most dramatically, so it gets the blame. But a gasket losing compression or a frame moving a few millimeters can turn a window into an opening while the glass is still in one piece.
02
"Tempered means protected"
Tempered glass handles heat far better than ordinary glass. But stronger glass is not indestructible glass, and it still relies on its surrounding frame, gaskets and hardware to hold it in place.
03
"Fire-rated means the whole system is rated"
The meaning of fire-rated can be confusing. Is just the glass or panel in the door frame fire-rated? The entire assembly needs to be rated. It's important to confirm the details.
04
"It passed a fire test, so it was engineered for wildfire"
A test answers the question it was designed to answer, and nothing more. Ask what was tested, how, for how long, and what counted as failure.
How California tests windows
Eight minutesis the minimumnot the goal
There is only one standard that requires the entire window assembly to be exposed to an open flame.
Four ways to comply with California's wildfire code
- Multilayered glazing with at least one tempered pane
- Glass block
- Glazing with a twenty-minute fire-protection rating (NFPA 257 or UL 9)
- Glazing that meets SFM Standard 12-7A-2
SFM Standard 12-7A-2
150 KW
A burner fires directly at the complete window for eight minutes. The window fails if flame gets through the frame or the glass, or if either gives way structurally.
08:00
Required
Revyn passed, then kept passing. Our window performed for so long that the testing team switched the burner off. At eight minutes, you could still put your bare hand on the inside of the window frame without burning yourself.
Before you specify
Questionsworth asking
Stop asking only "Does it meet code?" and start asking "What was this entire system engineered to survive?"
- What, exactly, carries the fire rating?
- Was the complete window tested, and how closely does it match what you are specifying?
- How long did it keep its integrity, and what counted as failure?
- Was wildfire actually in the engineering brief?
- What is the frame made from, which grade, and which mill produced the steel?
- How is the frame thermally broken, and what happens to that under prolonged extreme heat?
- What happens to the window after the fire?
Fire protection questions
Straightanswers
What is SFM 12-7A-2?
State Fire Marshal Standard 12-7A-2 is California's flame-exposure test for complete exterior windows. A 150 kW burner fires at the window for eight minutes, and it fails if flame penetrates the frame or glass, or if either fails structurally.
Does a steel frame make a window fire resistant?
Not by itself. A steel frame can still fail through its thermal break, gaskets, seals or hardware. Fire performance belongs to the complete assembly.
Why does the thermal break matter in a fire?
In many thermally broken steel windows, poured or crimped polyamide plastic holds the two halves of the frame together. It reduces heat transfer, but it also forms part of the structural connection, and under extreme heat or stress that connection can weaken. Therma Web™ separates the two jobs: the steel carries the structure and the thermal break insulates.
Can a Revyn window be reused after a wildfire?
Yes. After fire exposure, Revyn windows can be returned to our factory for complete reconditioning, so you keep your original investment instead of starting over.
Sources
- California Wildland-Urban Interface Code, Section 504.8, Exterior glazing
- SFM Standard 12-7A-2, Exterior Windows, California Referenced Standards Code, Chapter 12-7A
- CAL FIRE wildfire statistics, as cited in Wide Open to Wildfire (Curran, Hopkins and Houghton)
Once a month
TheSteel Report
Steel windows and doors are changing fast. The Steel Report keeps architects and contractors ahead of the game with industry news, engineering breakthroughs, architectural innovations and the performance standards worth building to. From energy efficiency and wildfire resilience to the life-safety issues that demand action, we report what changed and how to use it in your next project.