For most door and frame assemblies is the only way to meet IBC 715.4.3.1 to add smoke seals to the sides and head? I am trying to confirm what I have found on-line and what the hardware consultant is telling me.
Not exactly. The door and frame must be labeled as a smoke assembly, which is identified with an “S” on the label. Reference Section 715.4.6.3 (2009 IBC) or Section 716.5.7.3 (2012 IBC).
So if the door and frame have the “S” on the label, then it meets the requirements of UL 1784, with or without seals.
HC tells me can’t do it without seals (either added at the factory or in the field).
Seals are still required, but the door and frame must have been tested with seals, unless it passed without them, which I believe is nearly impossible. Some doors are provided with their own seals.
My guess is that to meet the S label requirements smoke seals are required. Since the label requires a tested assembly I’m not sure how field applied seals will work. If they are designed as part of the tested assembly to be field installed I presume it’s a possibility.
We should probably reach out to George Everding for this one.
UL 1784 isn’t specific about the test samples. The standard is used to test complete door assemblies or gasketing systems for specific door assemblies.
Therefore, the door and frame assembly is tested either with integral seals or field-applied seals. If field-applied seals are used, the manufacturer may provide the seals with the door and frame for field application after field finishing, or the use of approved seals that have passed UL 1784 as a gasketing system.
So far I understand and it makes sense. What is peoples experience with a pair of doors? Is a seal typically needed at the 1/8" gap between the two doors? I am being told that typically the door bottom does not need to be sealed to pass the UL 1784 test.
Bottom seals are not required, but a seal between a pair of doors is required.
I think those steel doors that are welded shut pass, provided the welds are continuous. They can’t be used in an egress path, however.
I agree with the discussion. This issue has come up with some of the architects I work with as a door hardware consultant, and a while back I put together a response to one of them, slightly edited and quoted here. Ron, if you would, check the accuracy of my interpretation of code. And Ken, thanks for the email tip to visit this discussion. Happy Holidays to all:
Its more complex than it needs to be the code sends us on a bit of a chase to track things down. As you state, 2009 IBC Section 715.4.3.1 requires fire door assemblies to meet UL 1784 smoke and draft control requirements. There is nothing specific in either reference about gasketing where and when it is required or what type it needs to be. IBC requirements are performance based: 3.0 cfm/sf of door opening at 0.10 H2O. In theory, a door assembly could pass UL 1784 with NO gasketing at all, but in reality it is difficult or impossible to achieve the required test values without gasketing. So we rely on the gasketing manufacturers, who test each of their products and list them as compliant with UL 1784 and appropriate for use on doors with smoke control requirements (S-labeled).
In addition to smoke control, IBC for several years has been requiring fire doors to be tested according to the UL10C positive pressure test that is more representative of an actual fire than the old negative or neutral pressure tests. Under UL 10C, a neutral pressure level is established at 40 inches above the floor, causing positive pressure forces against the door assembly above the neutral line. Because hot gases leak out in the positive pressure area, wood doors require an intumescent sealing system either built into the door, or applied to the frame. Once again, we rely on gasketing manufacturers to test their products as compliant with UL 10C.
Regarding the door bottom, there has been much confusion in the past about the requirement for a bottom seal. Under the UL 10C testing procedure, the sill of the door is under negative pressure because the neutral line is at 40 inches. Therefore we typically dont specify door bottom seals for fire rated openings. Examples of exceptions are: 1) where there is a sound control requirement; 2) where there is a mechanically pressurized space such as a pressurized stairwell, a laboratory space, or a mall; or 3) where the authority having jurisdiction requires a door bottom in addition to the code requirement. Note that if a door bottom is used even if not required by code, it still needs to be rated accordingly to the rating of the door, just like any other item of hardware.
Now, one reason for the confusion over the door bottom is that the UL 1784 test calls for an artificial door bottom installed at the sill of the specimen door being tested. The reason UL does this is that the test is meant to evaluate gasketing at the door edges (head and jambs) and since there is no neutral pressure line in this test protocol like there is in UL 10 C, if the bottom were left open it would skew the test results on the gasketing. And in fact, when IBC came out with these requirements, they put out an interpretation clarifying that they did not require a door bottom to be installed in the assembly it was only a requirement for the test apparatus.
George: I think you nailed it.
Former colleague at Allegion Lori Greene had a related post in her “I Dig Hardware” blog recently: http://idighardware.com/2014/08/gasketing-on-stair-doors/