Printed from the blog of Lori Greene, AHC/CDC, CCPR, FDAI
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May 20 2015

WW: Mullion, you’re doing it wrong.

Lee Frazier of Allegion sent me this Wordless Wednesday photo. I was confused.

Mullion 4

MullionThen I realized that what I was looking at was a removable mullion that was not mounted behind the doors as it was designed, but between the doors, leaving visible gaps along the lock edge of each door.  The black spacers are needed because the backset of the panic hardware was calculated based on the normal (and correct) mounting location of the mullion.

I know that some of you are hysterical right now, and others are scratching your head.  It’s sort of a “you had to be there” kind of thing, without any of us actually being there.  In a nutshell, the frame was ordered a couple of inches too wide because someone didn’t understand removable mullions.

You can learn more about removable mullions by clicking the graphic on the right, and there is a video here.  I have to say…I have run into lots of architects who had a tough time understanding how a removable mullion works, but I have never seen one installed like this.

Mullion 1

Mullion 2

Mullion 3

16 Responses to “WW: Mullion, you’re doing it wrong.”

  1. Eric Andrews says:

    Thanks for this! While I’m an architect, I currently work as an owner’s advocate and recently went round and round with an architect about this very issue. He didn’t understand how a removable mullion worked and insisted on scheduling frames with 6′-2″ openings. I eventually had to forward him the exact same diagram you attached.

  2. lach says:

    How do the mounting screws not rip out of the frame or just plain bend?

  3. Bert Axelson says:

    I can say its a first for me. Generally I’ve seen my installers do just about everything (Right or wrong). I bet those rubber setting blocks that they used for shims are plenty sturdy. The bonus is in the event of a fire the blocks melt and the firemen can enter the building without an emergency key (along with everyone else) ! I also wonder how many purses get hung up on those strikes.

  4. TOM CHIN says:

    I have seen that done on retrofits where they make the doors smaller to fit around the mullion.
    I guess you can put a square peg in a round hole

  5. Eric says:

    Rhetorical question; did the installer not read the mullion instructions and cut the door width to accommodate the mullion or did the door supplier not read the mullion template and made them the incorrect size? If it’s the latter, the installer still didn’t read the instructions.

  6. Keith Krienke says:

    So horrible. I would like to say I am shocked but frankly we all see stuff like this all the time.

  7. Pete Schifferli says:

    Totally unacceptable, replace frame or order wider doors.

  8. Tom Breese says:

    Another fix: *if* the opening is non-fire-rated, fabricate a steel tube mullion made from 2″x4″ steel, or weld another Von Duprin mullion to this existing one. It’ll have to fasten kinda odd-like, but doable (I think). Worth a shot?

  9. Bryan McKeehan says:

    I’ve seen some stupid stuff over the twenty plus years I’ve been installing doors and hardware but this one takes the cake.

  10. Khozema Kazi, AHC, FDAI says:

    How could this opening possibly not appear on the snag list before project handover?

  11. John Picciotti says:

    Hollow metal manufacturers make a removable HM mullion that fits between the doors and would have fixed the problem

  12. David Barbaree says:

    I agree with the above comments. This is another good example of why expert door and hardware punchlists are an essential part of the project turnover. This kind of stuff happens a lot in schools.

  13. Safecrackin Sammy says:

    I’ve seen this a lot in retrofit situations… Someone decides to replace a rabbeted fixed center mullion with a KR mullion for floor machine access etc. About the time they are ready to mount the strikes the issue becomes apparent…

    Applied stop to cover the gap and block up the strikes is about the only cheap fix if its not a FR opening.

    We like to shoot for unequal leafs where its allowed to give wider access for machines. Even though there is a removable mullion there, people will still try to squeeze machines thru without taking it out.

  14. Vincent Chestnut says:

    Where did they get all those spacers? I need some for my next install….

  15. Scott Foley says:

    so bad,made me laugh 🙂

  16. Richard McKie says:

    We have just had a builder do some monumental hardware screw-ups while doing an addition in one of our schools but nothing like that! (Example- On an access controlled pair the auto-opener was installed on the left door, the electric strike on the right!)I really do feel for the installer. He probably got the call on Friday afternoon and had to have the opening secure for the weekend.

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