further research::
Are hold down clips necessary when following a UL design?
Amstrong Fire Guard ceilings do not require the use of "hold down" clips in a UL design. Hold down clips are only required for UL assemblies in which the ceiling panels weigh less than 1.0 lb./square foot. All Armstrong Fire Guard ceilings weigh 1.0 lb./sq.ft. or more and do not require hold down clips.
How do I obtain an hourly rating for a corridor?
Below is a list of construction practices used in the industry to obtain an hourly rating for a corridor:
•If the corridor walls do not go to the deck, find the appropriate UL Design and install the specified fire-resistive ceiling and fire-resistive grid in corridor ceiling and adjacent areas.
•If the walls in the corridor run to the deck above, find the appropriate UL Design and install the specified fire-resistive ceiling and fire-resistive grid in the corridor ceiling; fire-damp where walls are penetrated.
•Install two layers of gypsum board in the corridor ceiling WITH CODE OFFICIAL APPROVAL, or reference the current 1997 Uniform Building Code section 1004.3.4.3.1 (2), page 1-115 Volume 1.
The above construction practices should be reviewed with your local Code Official before construction.
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