If you’re not in the habit of reading NFPA 80 cover-to-cover each time it is updated, this one might have slipped by you. It’s an important change. Let’s start with a (trick) question:
What is the maximum hole diameter that can be drilled on a fire door assembly in the field, as a job-site preparation for surface-mounted hardware?
I think I just heard a lot of you say that the maximum diameter of the allowable holes is 1 inch, with the exception of holes for cylinders (which may be larger than 1 inch). While this limitation is still stated in NFPA 80 – Standard for Fire Doors and Other Opening Protectives, the 2016 edition includes a new paragraph:
188.8.131.52.3 Holes exceeding a diameter of 1 in. (25.4 mm) shall be permitted for surface-applied hardware installed in accordance with the door manufacturer’s listing and the hardware manufacturer’s listing.
Could that be true? Holes larger than 1-inch diameter may be allowed to be drilled in the field? I checked the NFPA 80 Handbook (you can buy a copy here), and it explains that electrified hardware frequently requires holes larger than 1-inch diameter. While paragraph 184.108.40.206.3 does not state that only holes for electrified hardware may be larger than 1-inch diameter, electrified hardware was likely what motivated the change.
Note that there are other limitations in NFPA 80 that apply to these holes. For example, NFPA 80 allows “round holes” and the common interpretation is that the larger holes described in 220.127.116.11.3 are still required to be round. And the holes must be allowed by the listings of the door manufacturer and the hardware manufacturer. When the hardware manufacturer’s installation instructions for a listed product show a field preparation for a hole, those installation instructions and templates are part of the listing file. This establishes that the hardware manufacturer’s listing allows the field prep. But the door manufacturer’s listings must also allow the prep, and confirming this could take a little extra legwork.
The 2016 edition of NFPA 80 is referenced by the 2018 editions of the model codes, so technically this change would apply in jurisdictions that have adopted a code referencing the 2016 edition of NFPA 80. With that said, it’s possible that the AHJ could allow the larger field-drilled holes as an equivalency.