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Oct 03 2016

WWYD? Manual Flush Bolts on Fire-Rated Pairs

flush-boltOne of the cardinal rules of fire doors is that they are required to be positive-latching – there must be an active latchbolt that automatically latches the door when it comes to a close.  For pairs of doors this typically means that automatic flush bolts must be used, but NFPA 80 includes a potential exception to this rule – manual flush bolts may be used on pairs of fire doors leading to rooms that are not normally occupied by people (where acceptable to the AHJ).  I have mentioned this before, but I still get questions on this topic so here’s some more info.

First a few important points…

  1. For health care occupancies, NFPA 101 requires corridor doors to be self-latching, including a specific requirement for automatic flush bolts on the inactive leaves of pairs, so the NFPA 80 exception for manual flush bolts does not apply to health care corridor doors.
  2. For elevator machine rooms, refer to this blog post, which addresses the need for positive-latching hardware on these doors.
  3. In many occupancies, manual flush bolts are not allowed in a means of egress.  In my opinion, this limitation would not affect rooms that are not normally occupied by people, but here’s an article that covers the egress aspect of manual flush bolts.
  4. If you’re looking for some basic information about flush bolts, this video might help.

And now…back to NFPA 80.  This is from the 2016 edition, but the language hasn’t changed in recent prior editions:* Manually operated, labeled, top and bottom flush-mounted or surface-mounted bolts on the inactive leaf of a pair of doors shall be permitted to be used where acceptable to the AHJ, provided they do not pose a hazard to safety to life.

From Annex A – Explanatory Material:

A. This provision limits their use to rooms not normally occupied by humans (e.g., transformer vaults and
storage rooms).

The next question is whether the inactive leaf of a pair of fire doors leading to a room that is not normally occupied by humans is required to have a door closer.  Since the inactive leaf doesn’t automatically latch when it closes, I think a closer could almost be detrimental here as the door could be closed and presumed latched even though the bolts are not projected.

NFPA 80 states:* Unless otherwise permitted by the AHJ, a closing device shall be installed on every fire door.

The exception that applies to this application is in Annex A:

A. It is the intent of the standard that most fire doors will have a closing device. However, in limited circumstances the closer might not be necessary because the door leaf is inactive and is normally in the closed position. Examples of such applications include pairs of doors to mechanical equipment rooms and certain industrial areas where an inactive leaf is provided and is infrequently used to permit large equipment to be moved through the door opening. In such instances, the AHJ should be reasonably assured that the inactive leaf normally will be closed and latched…

So here are the questions for you…

  • What do you typically specify for the inactive leaf of a pair of fire doors leading to a room that is not normally occupied by humans? 

  • Do you request prior approval from the AHJ when specifying manual flush bolts on fire doors? 

  • Have you ever had an AHJ reject the use of manual flush bolts on these doors?

  • WWYD?

11 Responses to “WWYD? Manual Flush Bolts on Fire-Rated Pairs”

  1. Mojo says:

    Manual flush bolts

  2. Bob Caron says:

    We typically use manual flush bolts on rooms that are not usually occupied by humans. As far as I know, no one has asked prior permission from an AHJ and the manual flush bolts on these rooms have not been rejected.

    Your picture of a corner type bolt brings up something else we just encountered. Many wood door manufacturers will machine for the extension type on rated doors and that is what we usually specify. I’ve seen a bulletin from Eggers that specifically says that they are approved to do so. I don’t know if the other manufacturers that we’ve used also have official approval but Marshfield definitely would not machine for them. We had to change the extension type to a corner type. With the corner type, the door corners tend to flair out over time. I think that some corner bolts come with screws that go through the face of the door and into the bolt housing but installers never put them in.
    Does anyone regularly use corner bolts on wood fire doors and do you get complaints later on?

    • Lori says:

      I never use corner wrap flush bolts…I only used the photo because it looks better than an uninstalled extension rod flush bolt. 🙂

      – Lori

  3. James Slemmons says:

    Maybe I’m oversimplifying, but I like constant-latching, semi-auto flush bolts, top only (security permitting) with a fire bolt.

  4. David Snell, AHC says:

    The only time I use manual flush bolts on labeled openings is in a small electric room, telecom closet or data closets that have storeroom function locks and would never be left unlock.

  5. Daniel Poehler says:

    I would always want an automatic flush bolt on the inactive leaf. Other than a little extra cost for a coordinator, I see no reason to do it any other way. A transformer vault is a good example of “not normally occupied”, but when changes to the electrical system are made, the room could be occupied by several people. Having automatic flush bolts answers the last three questions.

  6. Chuck Park says:

    When I was employed by a large, NYC metro area medical center, we would routinely spec pairs of doors for mechanical rooms, electric closets, and pipe chases with manual flushbolts and no closer on the inactive leaf. The only time the inactive leaf was opened on these rooms was on a rare occasion when a large piece of permanent mechanical/electrical equipment was being replaced.

  7. Jerry Richmond, AHC/CDC says:

    Manual flush bolts.
    For wood fire doors needing automatic flush bolts, I spec’d the Rockwood 2962 to avoid the weakened and spreading corner issue.

  8. Robert says:

    There is a question to be asked to the group is : if a door? is a door? that has no handle or latch if there is a flush bolt. Is this a movable wall or can be ID with other name as I have to ask if the inactive leaf is a door that has no latch or handle? Just because it has hinges does not make it a door does it?

    • Lori says:

      Hi Robert –

      I think an inactive leaf with flush bolts is usually considered a door – even if it doesn’t have a handle.

      – Lori

  9. Leo says:

    On Mechanical Rooms in Hospitals or Schools I would use the Auto, but in an Office Building where things like Coordinators can get neglected and they will stop to perform properly I think that manual flush bolts is a safer way to go, that way you know it’s inactive and you have to manually close them and not rely on the coordinator that is not functioning properly anymore.

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