Printed from the blog of Lori Greene, AHC/CDC, CCPR, FDAI
Allegion
Email: lori_greene@allegion.com, Blog: www.idighardware.com or www.ihatehardware.com


Jun 23 2011

Doors in Pockets (not Pocket Doors)

Category: Door Closers,Doors & Frames,Fire DoorsLori @ 10:08 am Comments (4)
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Every time I specify hardware for a door that swings into a pocket, a little alarm sounds in my head because at least 50% of the time there will be a problem that urgently needs to be fixed at the end of the job.  This application requires coordination between the architect designing the pocket, the contractor building the pocket, and the distributor supplying the doors and hardware, and that’s a lot harder than it sounds.  The other problem is that when one pair on a project goes south, in most cases ALL of the pairs are a problem.

The doors I’m talking about are usually cross-corridor pairs, and when they swing open to 90 degrees they sit in a pocket and the face of the door is flush with the face of the wall.  In order for this to happen, the door needs to swing out of the opening so the door edge is aligned with the face of the frame, rather than sitting out in the clear opening width.  I have occasionally seen this done with swing clear hinges, but that leaves a large gap between the face of the frame and the door edge.  The best way to hang the door in this application is with pocket pivots.

If a standard surface-mounted or concealed closer is supplied, the arm will be visible when the door is standing open.  I like to specify a wall-mounted closer that sits in the pocket, like the LCN 4000T.  When the door is open, the closer is completely hidden behind the door.  These doors are almost always held open and only closed upon fire alarm actuation.  The coordination problem that arises is that the pocket has to be the correct size.  A pocket that’s not deep enough won’t leave enough room to mount the closer, and a pocket that’s too deep will result in the wrong geometry for the closer to work properly.  The length of the pocket also needs to be coordinated, so there is enough space to open the door but without a large gap.

The magnetic holder and the projection of the lever handle also need to be considered.  The lever handle has to fit within the allowable pocket depth, and the magnetic holder ultimately controls where the door will sit when it’s fully open, and whether it will be flush with the wall or not.  It also affects whether there is enough space for the door closer and lever handle.

In the 4000T section of the LCN catalog, there’s a handy graphic to help with this coordination.  —>

  • Dimension 1 is the distance from the centerline of the closer shaft to the centerline of the hinge or pivot. For pocket pivot or total door hinge, 9 1/2” (241 mm). For butt hinge 8” (203 mm). For center pivot 10” (254 mm).
  • Dimension 2 is the distance from the centerline of the pivot or hinge to the cylinder mounting surface. For pocket pivot 4 1/2” (114 mm). For total door hinge 3 7/8” (98mm) For butt hinge 2 7/8” (73 mm). For center pivot 4 1/2” (114 mm).
  • Dimension 3 is the distance from the centerline of the pivot or hinge to end of the track. For pocket pivot or total door hinge, 3 7/8″ (98mm). For butt hinge 2 3/8″ (60mm). For center pivot 4 5/8″ (117mm).

I saw a great example of this application the other day, and I thought it was interesting that the UL label was on the lock edge instead of the hinge edge.  It makes perfect sense since you wouldn’t be able to see a label on the hinge edge, but I’ve never seen it that way before.  I would have used a less-conspicuous finish on the hardware, but the pocket was perfectly coordinated.

 

 

4 Responses to “Doors in Pockets (not Pocket Doors)”

  1. Jim says:

    Lori, I agree about the finish. Using the pocket usually indicate a desire to hide the doors or at least reduce the profile. I would use a recessed exit device [94/96 IMPACT] in a US28 finish. That would reduce the profile of the door significantly and the lighter colored finish would be less noticable. Based on the photos, it looks like it was a good installation.

  2. Scott Tice says:

    For residential we use a SOSS hinge or what is commonly referred to as a Harmon hinge. Not cheap.

  3. Dr is in says:

    Cross corridor doors need vision lites by code, correct? What about when you are trying to build the door into a pocket with it on hold opens, does it still need the vision lite? The reason we would build the door into a pocket is to have it blend in with the wall, however having to have the windows would negate this. I seem to see doors in pockets without windows all the time, however I cannot see where this is allowed in any life safety code or other. Is there a way the the doors built into the pocket would not require the vision lites?

    Thank you.

    • Lori says:

      That’s a really good question. Doors in pockets don’t have lites, but the IBC and NFPA 101 require lites in certain locations. There isn’t a special provision for doors that are held open in a pocket…I’m surprised this hasn’t come up more often. Here are the locations in the IBC and NFPA 101 where I found a requirement for vision lites:

      2009 IBC:

      710.5 Openings. Openings in a smoke barrier shall be protected in accordance with Section 715.
      Exceptions:
      1. In Group I-2, where doors are installed across corridors, a pair of opposite-swinging doors without a center mullion shall be installed having vision panels with fire-protection-rated glazing materials in fire-protection-rated frames, the area of which shall not exceed that tested. The doors shall be close fitting within operational tolerances, and shall not have undercuts in excess of 3/4-inch, louvers or grilles. The doors shall have head and jamb stops, astragals or rabbets at meeting edges and shall be automatic-closing by smoke detection in accordance with Section 715.4.8.3. Where permitted by the door manufacturer’s listing, positive-latching devices are not required.

      Commentary: When double egress corridor doors are provided, they are required to have a vision panel consisting of protection-rated glazing, in accordance with Section 715.4.7. Vision panels are required to reduce the likelihood of an injury caused by opening the door into a person standing at or approaching the door from the opposite side. Vision panels also enable an individual to be alerted to a fire or smoke condition on the other side before opening the door.

      715.4.7.2 Exit and elevator protectives. Approved fire-protection-rated glazing used in fire door assemblies in elevator and exit enclosures shall be so located as to furnish clear vision of the passageway or approach to the elevator, ramp or stairway. The purpose of vision panels in exit doors and elevator doors is to permit observation by occupants who may be on the opposite side of the door before opening it. The limitations on the size of panels in Section 715.4.6.1 still apply.

      2009 NFPA 101:

      New Health Care:
      18.2.2.5.6 An approved vision panel shall be required in each horizontal exit door.
      18.3.7.9* Vision panels consisting of fire-rated glazing or wired glass panels in approved frames shall be provided in each cross-corridor swinging door and at each cross corridor horizontal-sliding door in a smoke barrier.

      New Ambulatory Health Care:
      20.3.7.11 A vision panel consisting of fire-rated glazing or wired glass panels in approved frames shall be provided in each cross-corridor swinging door and at each cross corridor horizontal-sliding door in a smoke barrier.

      New and Existing Detention:
      22.3.7.10/23.3.7.10 Vision panels shall be provided in smoke barriers at points where the barrier crosses an exit access corridor.

      New and Existing Residential Board and Care:
      32.3.3.7.18* Vision panels consisting of fire-rated glazing or wired glass panels in approved frames shall be provided in each cross-corridor swinging door and in each cross corridor horizontal-sliding door in a smoke barrier.

      Occupant Evacuation Shaft System:
      B8.8 (3) Each door shall be provided with a vision panel arranged to allow people within the lobby to view conditions on the other side of the door.
      B.8.9 Each occupant evacuation shaft system exit stair enclosure door shall be provided with a vision panel arranged to allow people on either side of the door to view conditions on the other side of the door.

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