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Can You Put Window Film on Fire-Rated or Wired Glass? What Codes, Glass Makers and Film Makers Say
Fire-rated glass is a listed product, and the film question starts with that listing. Here is what California’s code, NFPA 80, UL, glass makers and film makers say, and who to ask. This is general information, not code, legal or warranty advice.
Published October 30, 2026 · Armored Glass Solutions
The Short Answer
Short answer: it depends on the glass’s listing, so ask before anyone touches it
There is no blanket yes or no. No code or listing document we read says in so many words that film is allowed or barred on fire-rated glass as a class. What they point to is the listing of that exact glass. California allows fire-resistance-rated glazing “where tested and installed in accordance with their listings”.
The clearest answer we found is a comment on an industry blog, posted in April 2023 by someone writing about a project by Technical Glass Products (TGP), a fire-rated glass company. Asked about film on fire-rated glass, the writer said “there is not a one size fits all answer.” It depends on “the specific glass type being used, the fire rated material OEM’s certified listing, and the specific film or product being applied.” The comment continues: “Typically, the combination needs to have been reviewed for use by either the independent third party responsible for the product’s certification (UL, Intertek | WHI, etc.) or have been approved by the local AHJ.” And: “Application of a film or other product, if not performed by the OEM, might be allowed for field application at the OEM’s discretion.”
OEM there means the glass maker. AHJ means the authority having jurisdiction, usually your fire marshal or building official. This is a blog comment and not a TGP policy document, and we did not confirm the writer’s role with TGP. Still, it names the people to ask: the glass maker, the listing agency and the AHJ. Then get the film maker’s position in writing for the exact film and glass. For the short version, see our post on decorative film on office glass walls and doors.
Start Here
How to tell if glass is fire-rated: read the mark
California’s 2025 Building Code says “Fire-rated glazing assemblies shall be marked”, and that the label has to be “issued by an approved agency” and “permanently identified on the glazing.” TGP’s FireLite sheet says “Each piece of FireLite shall be permanently labeled with the FireLite logo, UL logo and fire rating.”
The letters in the mark stand for specific tests:
- D. The glazing “is permitted to be used in fire door assemblies”.
- H. It “meets the hose stream requirements” of the door test standards.
- T. “Meets 450°F temperature rise criteria for 30 minutes”.
- W. “Meets wall assembly criteria.”
- OH. “Meets fire window assembly criteria including the hose stream test.”
- The number. The “fire-rating period, in minutes”. The code’s own examples include “D-H-W-60” and “D-H-OH-45”.
The code also separates two kinds of glass. Fire-protection-rated glazing and fire-resistance-rated glazing have different size limits, and only the second is tested as a wall. TGP’s fact sheets for two of its products note “This product is not a barrier to radiant heat”, because they don’t meet the wall test standards.
The mark tells you what the glass is, not whether a film is acceptable on it.
The Rules
What the code and NFPA 80 expect from a rated door lite
California’s code says opening protectives “shall be installed in accordance with NFPA 80”, and it references the 2022 edition. We read NFPA’s committee documents, not the published standard, and some of that text is for the later 2025 edition. Wording and numbering can differ, so we cite requirements and not section numbers. Those documents show:
- Labeled glazing only. “Only labeled fire resistance or fire protection glazing material shall be used in fire door assemblies when permitted by the door listing.”
- What an inspector looks for. Glazing that is “intact and securely fastened in place”, and “No field modifications to the door assembly have been performed that void the label.” The list for power-operated doors adds “Labels are clearly visible and legible.”
- No signs on the glass. “Signs shall not be installed on glazing in fire doors.” NFPA 80 says signs. No source we read says window film counts as a sign, so ask whether your film would be treated the same way.
We found no source on film over the label. The code wants the mark permanently on the glass and the checklist wants labels legible, but nothing we read says whether film laid over a mark breaks either one. That is a question for the AHJ and your fire-door inspector.
Lori Greene of Allegion, a door-hardware code expert, describes two kinds of field work. Job-site preparations are changes “specifically allowed by NFPA 80”, such as round holes for hardware and protection plates. Field modifications “must be approved in advance by the listing laboratory”. Film is not on the list she gives. We read that as ask the lab first, though that is our reading and not her statement.
UL Solutions says its fire door inspections “do not field certify any modifications or additions of components”, and that its “field evaluation services are the appropriate option to evaluate modifications or changes to a fire door assembly”. That page does not name glazing film. Neither do the glazing trade body’s Fire-Rated Glazing 101 or UL’s door and window application guide, and their silence doesn’t answer the question either way.
Factory Film
Film that is already part of a listing
Film and fire-rated glass already exist together, as factory products:
- TGP FireLite NT. A ceramic glass with a surface-applied film, “listed for use in doors, sidelites, transoms and borrowed lites”. The sheet says it is “Classified and labeled by Underwriters Laboratories”.
- TGP WireLite NT. Wired glass with a surface-applied film. TGP says “Fire-rated for up to 90 minutes with required hose stream test” and “Impact safety-rated”.
- Vetrotech Keralite. Vetrotech’s care sheet says “The film is applied on the opposite side of the UL stamp / logo.” It says nothing about aftermarket film.
Here the maker chose the film and applied it, and the result carries the label. That tells you nothing about a different film added later on site. TGP’s plain FireLite sheet allows one change: it “May be lightly sandblasted or etched on one side without affecting fire rating”. It doesn’t mention film.
Added Later
Aftermarket film: what glass makers and film makers say
The listing view. Greene writes: “The product would have to be listed for use on a fire door assembly, which would typically mean testing it with various types of glazing.” We did not search the UL or Intertek directories, so we can’t tell you whether any such listing exists today. Your listing agency can.
SAFTI FIRST’s caution. SAFTI, a fire-rated glass company, wrote in 2015 that putting safety film on wired glass without testing and certification is “a highly dangerous practice that violates code requirements”, and that some films “can actually contribute to the spread of fire.” It said film on existing wired glass “must be done under the guidelines of a certified field filming program”. Weigh that with its context. SAFTI sells competing products, and a 2006 press release says it holds a patent that “covers any filming of wired glass, either applied at the manufacturing plant or in the field”. We found no code text that says this about film. A 2011 article on SAFTI’s site says Intertek reviewed a SAFTI training program on field filming. We don’t know whether any such program runs today.
Madico CL 800 PS SR. Fire Glass Film is Madico’s product name, not a fire rating. Its page says “Meets safety glazing requirements for fire-rated, ceramic, and wire glass applications.” Its 2018 sell sheet says it “can be applied in retrofit applications to existing glass”. The sheet lists a surface-burn test (ASTM E-84), ignition temperatures (ASTM D-1929) and impact results (ANSI Z-97.1 and CPSC Category II). It does not list UL 9, UL 10B, UL 10C, NFPA 252 or NFPA 257, gives no listing file number, and doesn’t say what glass the impact tests were run on. It doesn’t say a fire-rated lite keeps its rating with the film on. Ask Madico and the glass maker in writing.
Glass warranties. A distributor’s 2019 Pyran Platinum warranty is void for product that “has been repaired or altered”. It doesn’t mention film, so ask whether the glass warranty treats film as an alteration.
What we couldn’t find. We found no statement on aftermarket film from Pilkington or Schott, and 3M’s bulletins blocked our downloads. We also found no test data we could verify on how film changes fire-rated or wired glass in a fire.
Wired Glass
Wired glass: why it is a special case
Federal rule. The federal safety-glazing regulation still exempts “Wired glass used in doors or other assemblies to retard the passage of fire”, where a fire ordinance requires the door or assembly. What changed is the building code.
Building code. In a 2015 trade article, Greene writes that the 2003 International Building Code stopped allowing traditional wired glass in doors and other hazardous locations in educational occupancies, meaning K-12 schools and daycare centers. She writes that the 2006 edition “removed the exception completely”, for any occupancy, where a jurisdiction has adopted that edition or later. We read her account, not the code-change records. California’s code now says fire-rated glazing in doors and windows must meet the safety-glazing chapter “where applicable”. That chapter’s default is “Category II”. Your building official applies those rules.
Overhead glass is a separate rule. California’s skylight sections list wired glass among allowed glazing. That is a separate rule from doors and other human-impact locations. See our post on skylights and sunrooms.
Options for existing wired glass. SAFTI’s 2015 list is “replacement with impact and fire resistant materials, coating the glass with specialty films and installing protective bars or railings.” SAFTI also said in 2014 that film “does not prevent the glass from breaking.” The same trade article describes a retrofit program that puts safety film on existing wired glass in hazardous locations “until they can be replaced”, and states its purpose as a “stopgap measure”. We have not verified that program with its vendor. If a film is used to meet safety glazing, also ask about marking: California requires each pane in a hazardous location to carry a permanent designation or label.
Solar film is its own problem. The International Window Film Association’s training guide says “Solar control window films should not be applied to the interior surface of any exterior facing wired glass.” Its reason: “The wire contained within the glass absorbs heat”, and “This can lead to glass breakage.” Film makers’ warranties differ:
- Madico commercial and residential (5/2025). Lists “Wired, textured or patterned glass” under “Prohibited Use - No Film Installation in These Instances”.
- Madico SafetyShield (12/2025). Bars “Solar control safety films installed on wired glass (clear films are approved on wired glass)”. That says nothing about a fire rating.
- Solar Gard (09/24, Hawaii form). No glass-breakage or seal-failure coverage on “Textured, wired or skylight glass”.
- SunTek (2021 guidelines). No warranty on thick glazing units “and wired glass.”
Before Anyone Orders
The questions to ask, in order
- 1. The glass maker, who holds the listing. Give them the mark. Does the listing permit an added film? Which ones, applied by whom? Is film an alteration under the warranty?
- 2. The listing agency (UL or Intertek). Has this film and glass combination been reviewed? Is a field evaluation the route for this door or window?
- 3. The AHJ, meaning your fire marshal or building official. Would they accept the combination? How do they treat film near or over the mark? Schools should also ask about Division of the State Architect rules and the California Fire Code, neither of which we read for this post.
- 4. The film maker, in writing. Name the exact film and glass. Ask what it was tested on and what the warranty says for that glass.
Our scope: we install film, overglaze and door reglaze. We don’t install replacement glass or fire-rated glass. That work goes to a glazing contractor. This post reports what others have written. It is not an offer to film any particular rated lite, and it is not code, legal or warranty advice.
Questions
Window film on fire-rated and wired glass: FAQ.
Can window film go on fire-rated glass?
There is no blanket yes or no. It depends on the glass's listing. TGP sells products such as FireLite NT and WireLite NT with a factory-applied film and a UL label. For film added later, a blog comment written about a TGP project says the combination typically needs review by the certifier or approval by “the local AHJ,” and that it “might be allowed for field application at the OEM's discretion.” Ask the glass maker, the listing agency and your fire marshal or building official, then get the film maker's position in writing.
How do I know if my glass is fire-rated?
Look for the mark. California's code requires the label to be “permanently identified on the glazing” and to show the manufacturer, the test standard and the rating. Marks such as “D-H-W-60” or “D-H-OH-45” use letters for the tests and a number for the minutes. The mark tells you what the glass is, not whether film is acceptable on it. If you can't find one, ask your fire marshal or building official.
Does film over the fire-rating label cause a problem at the annual fire-door inspection?
We found no source that addresses film over the label. NFPA committee documents list inspection items such as “Labels are clearly visible and legible,” intact glazing and no field modifications that affect the label. They also say “Signs shall not be installed on glazing in fire doors.” No source we read says film counts as a sign. Ask your fire marshal or building official and your fire-door inspector before film goes on.
Does safety film solve the problem with old wired glass?
It depends on what the problem is and who has to accept the fix. SAFTI FIRST, which sells competing products, said in 2014 that film “does not prevent the glass from breaking.” A 2015 trade article describes a retrofit film program as a “stopgap measure” until the glass can be replaced. Factory-filmed wired glass such as WireLite NT carries its own listing and impact rating, which is a different thing from film added on site. Ask your building official what they will accept.
Why won't some installers put solar film on wired glass?
Heat and warranties. The International Window Film Association's training guide says “The wire contained within the glass absorbs heat” and that solar film on the inside of exterior wired glass “can lead to glass breakage.” Madico's commercial warranty lists “Wired, textured or patterned glass” under prohibited uses, and Solar Gard and SunTek limit warranty coverage on wired glass. Madico's SafetyShield form approves clear films on wired glass, so ask the film maker about the exact product.
Sources
Where these findings came from.
We read most of these on October 29, 2026, and re-read the TGP blog comment on October 30. The glazing trade body’s guide and UL’s application guide were read earlier in October 2026. We read NFPA committee documents and not the published NFPA 80. We did not search the UL or Intertek listing directories. We did not read the California Fire Code or Division of the State Architect rules. Makers’ statements are about their own products, and some of these documents are several years old, so current versions may differ. This post is general information, not code, legal or warranty advice.
- 2025 California Building Code (Title 24, Part 2), Chapters 7, 24 and 35, read on UpCodes. Adopted code. Link.
- NFPA 80 committee documents: Second Revision Report (Annual 2024 cycle). NFPA committee document, not the published standard. Link.
- NFPA 80/105, First Draft Meeting Agenda (10/2022). NFPA committee document. Link.
- NFPA 80, Public Input Report (Annual 2021 cycle). NFPA committee document. Link.
- 16 CFR 1201.1, read on Cornell Legal Information Institute. Federal regulation. Link.
- UL Solutions, UL Fire Door Inspection and Field Evaluation Programs: What Are the Differences? Listing agency. Link.
- Comment of April 17, 2023 on TGP: Street Talk, iDigHardware. Blog comment by someone writing about a TGP project; role not confirmed with TGP. Link.
- Lori Greene, WWYD? Glazing Films, iDigHardware, June 2024. Industry expert. Link.
- Lori Greene, QQ: Adding / Enlarging Vision Panels in Fire Doors, iDigHardware, January 2023. Industry expert. Link.
- Lori Greene, The hazards of traditional wired glass, The Construction Specifier, July 2015. Trade press. Link.
- TGP, FireLite fact sheet. Glass maker. Link.
- TGP, FireLite NT fact sheet. Glass maker. Link.
- TGP, WireLite NT product page. Glass maker. Link.
- Vetrotech Saint-Gobain, Care & Cleaning Instructions (August 2024). Glass maker. Link.
- General Glass International, Pyran Platinum Fire-Rated Glass Warranty (2019). Distributor. Link.
- SAFTI FIRST, Wired Glass Still a Misunderstood Product (June 3, 2015). Glass maker with competing products. Link.
- SAFTI FIRST, article on existing wired glass (April 10, 2015). Glass maker with competing products. Link.
- SAFTI FIRST, article on wired glass (October 7, 2014). Glass maker with competing products. Link.
- SAFTI FIRST, NFPA 80 Code Changes Force Industry Response (from Doors and Hardware, June 2011). Glass maker with competing products. Link.
- SAFTI FIRST, US Patent for SuperLite I-W, Safety Wired Glass, press release (September 26, 2006). Glass maker with competing products. Link.
- Madico, commercial and residential warranty form M956144 (5/2025). Film maker. Link.
- Madico, SafetyShield warranty form M956170 (12/2025). Film maker. Link.
- Madico, CL 800 PS SR Fire Glass Film product page. Film maker. Link.
- Madico, CL 800 PS SR sell sheet (2018). Film maker. Link.
- Saint-Gobain Solar Gard, limited warranty form SK0364HI 09/24 (Hawaii installations). Film maker. Link.
- Eastman SunTek, Film Installation Guidelines (2021). Film maker. Link.
- International Window Film Association, Flat Glass-Solar Education Guide 2023. Industry association. Link.
- Glass Association of North America, Fire-Rated Glazing 101 (FB76-23). Trade body. Link.
- UL, door and window application guide. Listing agency. Link.
Keep Reading
Related reading.
Decorative film on office glass walls and doors
What to check before frosted or decorative film goes on an office glass wall or door.
Read the post →Security film on bedroom and escape windows
What California’s escape-opening rules say about film, and what a federal fire-service test found.
Read the post →Window film on skylights and sunrooms
What changes with overhead and sloped glass, including wired glass in skylights.
Read the post →Not sure what your glass is?
Call us with the mark on the glass and we will talk through who to ask first and what to get in writing. If film turns out to be a fit, we put the product and the terms in writing. Call (310) 488-5626 or 888-960-TINT.