Field Modifications on a 90-Minute Stair Door
A hospital is renovating a four-story stair enclosure. The stair doors are labeled 90-minute. A subcontractor has: (a) drilled a ½-inch peephole viewer through the steel door at 60 inches above finished floor; (b) installed a surface-mounted slide bolt on the corridor side of the door; (c) relocated the closer 4 inches by drilling new holes and filling the old holes with putty; and (d) after installing ¾-inch tile, the door now drags on the floor, and the crew plans to cut ½ inch off the bottom. The door label is intact and legible. The contractor says the viewer is “just like the ones in hotels” and the bolt is for security.
1. Evaluate each modification against NFPA 80 field-modification requirements and the door’s listing.
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Viewer (a). A hole through a labeled door is a field modification. It is permitted only if the viewer is listed for fire-door use and installed per the manufacturer’s published instructions. “Like the ones in hotels” is not a listing. If the device is not listed for the door, the label is compromised and the assembly cannot be treated as a 90-minute door.
Slide bolt (b). The corridor side of a stair door is the egress side for occupants entering the stair. A slide bolt adds a second operation and is not permitted as egress hardware. Even on a non-egress face, it would have to be listed auxiliary hardware that does not interfere with closing or latching; a surface slide bolt does not meet that test.
Closer relocation (c). New holes must follow the door manufacturer’s template and reinforced areas. Drilling outside the prepared area and filling abandoned holes with putty is not an approved repair; abandoned holes must be sealed with listed plugs or fasteners. Putty does not restore fire resistance.
Bottom cut (d). The door must maintain clearance and must not drag. Cutting a labeled door is a field modification that requires the manufacturer’s written instructions. A ½-inch cut may expose the core or stiffeners and is not automatically permitted.
2. What are the acceptable ways to resolve the floor-clearance problem without compromising the label?
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First determine the actual clearance and the cause. If the tile raised the finished floor, the preferred solutions are to adjust the frame or hinges, modify the floor transition, or install a listed automatic door bottom within the manufacturer’s limits. Do not simply cut the door.
If trimming is unavoidable, obtain the door manufacturer’s written field-cutting instructions for that specific door construction and rating, and have the work performed and documented accordingly. For many steel doors only limited bottom trimming is allowed; for wood doors, cutting can expose the core and is usually prohibited. If the manufacturer will not approve a cut that restores clearance and latching, the correct answer is to replace the door or rework the opening.
After correction, retest self-closing and latching from a fully open position and verify the clearance at the frame and floor. Record the manufacturer’s instructions, the work performed, and the retest result.
3. Who should approve and document these changes, and what belongs in your report?
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Approval authority rests with the door and frame manufacturer for field modifications and with the authority having jurisdiction for the installed assembly. The contractor cannot self-approve a modification by asserting equivalence.
Your report should list each opening, describe the modification, identify the product and whether it is listed for fire-door use, cite the applicable NFPA 80 requirement, and state whether the label remains valid. Where a modification is not permitted, state that the assembly no longer qualifies at its labeled rating until corrected or replaced. Include photographs, the date, the persons interviewed, and the manufacturer’s response if obtained. Distinguish immediate life-safety items, such as an egress-side slide bolt, from items requiring follow-up documentation. Send the report to the owner and, where required, to the AHJ; do not rely on the contractor to forward it.