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Are Fire Door Assemblies with sidelights limited to 25% of the a common wall?

Harrison Staab

Harrison Staab

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Manhattan, KS
2015 IBC Section 716.5 Fire door and shutter assemblies.

Say you've got a fire door assembly with multiple individual sidelights. The wall is a 1-hr fire partition - a corridor wall. Door is a side hinged door.

It appears the assembly has the following limitations:
  • Required to be tested with NFPA 252 or UL 10C per 716.5.1
  • The door vision panel (the glazing in the door itself) is required to be D-20 labeled to the maximum size tested
  • Fire door frames with sidelights and transoms are required to be 3/4-hr rated with D-H-OH-45 glazing for 1-hr corridors per Table 716.5 and 716.5.6
  • Fire-resistance glazing shall comply with the size limitations of NFPA 80 per 716.5.8.1
  • NFPA 80 specified max area of glazing is "limited to maximum area tested" for 3/4-hr applications
It appears to me that this particular fire door assembly would only be limited to the maximum tested assembly and that there is no other area or dimensional limitation of the code. I understand that there are manufacturer limits to the size of their tested assemblies (about 150 sf area / 13' widths as I have found).

A plan reviewer has cited 716.6.7.2 which says "The total area of the glazing in fire-protection-rated window assemblies shall not exceed 25 percent of the area of a common wall with any room." However, this appears to be specific only to fire window assemblies. 716.6 refers glazing in fire door assemblies to 716.5.8. The commentary on 716.6 says "This section covers glazing in fire windows, not fire doors.."

Online commentary on this issue appears limited, but SAFTIFIRST has a few posts that interpret the 25% limitation to include any fire-resistance-rated glazing. For example, see http://safeglassforschools.com/code.../fire-rated-glazing-in-1-hour-exit-corridors/

In the example sketch attached, if the 25% were applicable, the glazed section proposed would be required to be a 1-hr UL 263 assembly to maintain the design intent.

Are Fire Door Assemblies with sidelights and transoms limited only by what has been tested? Or are they also subject to the 25% limitation of 716.6.7.2?

Thanks in advance for your insight.
 

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Sidelights and transoms are not part of the fire door assembly (see definition in Chapter 2)--they are considered fire windows and subject to the limitations cited.
 
RLGA said:
Sidelights and transoms are not part of the fire door assembly (see definition in Chapter 2)--they are considered fire windows and subject to the limitations cited.
Click to expand...

To be clear my interest is in sidelights connected to the door frame.

Fire door assembly. Any combination of a fire door, frame, hardware and other accessories that together provide a specific degree of fire protection to the opening.
Fire window assembly. A window constructed and glazed to give protection against the passage of a fire.​

Does this not include sidelights and transoms that are integral to (not separate from) the door frame?

Section 716.5 on fire doors seems to include discussion on transoms and sidelights. Section 716.6 on fire windows seems to kick such glazing back to 716.5. Glazing for fire windows in a 1-hr fire partition is required to be marked OH-45 per Table 716.6. However glazing for sidelights of fire door assemblies is required to be marked D-H-OH-45 per Table 716.5.

From what I see, manufacturers specifically delineate fire window systems from fire-door assemblies which include transoms and sidelights in the frame. It appears NFPA 80 includes transoms and lites as part of the fire door frame (see Appendix A.3.3.52). The UL door and application guide, associated with UL listings for fire doors also mentions transoms and sidelights as part of the frame - http://productspec.ul.com/document.php?id=GVTV.GuideInfo (see bottom of Door Frames section and Product Identity section which includes door frames with sidelights) and https://legacy-uploads.ul.com/wp-content/uploads/2014/04/DoorWindowAG.pdf (see page 13). Various manufacturers I'm researching include assemblies with sidelights as part of the fire door assembly.

Am I missing something?
 
Sidelights and transoms are separate and different from the door requirements.
You could always use 1 hour glazing in the windows and then it is treated as a wall and not subject to the area limitations.
 
JPohling said:
Sidelights and transoms are separate and different from the door requirements.
You could always use 1 hour glazing in the windows and then it is treated as a wall and not subject to the area limitations.
Click to expand...

Agreed, but as I've laid out, I think they are subject to the glazing requirements section within fire door assemblies (716.5.8) not fire window assemblies. The assembly in question is not a large opening, but the room it opens does not have a great length of common wall with the corridor so the 25% limitation would be hard to meet with any additional sidelight. I've done similar fire doors with sidelights in other projects as described and haven't run into this before now. I prefer not to upgrade the assembly to a more expensive 1-hr glass wall system if I can help it.
 
I am not into fire windows,

But should your question be:::


“”The total area of the glazing in fire-protection-rated window assemblies shall not exceed 25 percent of the area of a common wall with any room.”””


How much common wall do you have??

I am thinking the corridor is your common wall,,, Are you thinking something else???
 
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