Nope and nope. From '02 8.14.1.2.3 has NO limitation on ceiling material. At least this is what I think you are after. You don't even need gypsum. Could in theory use expanded foam, ACT, plywood, dimensional lumber or what ever you could think up. Now I won't recommend expanded foam of course. I'd say it has to be thermally thick enough not to melt or retract before sprinkler activation and at reasonable sprinkler controlled fire gas temperatures. So tissue paper and nylon/spandex are bad choices.
And with your description not sure where the combustible concealed space is. 2 x 9 is usually obstructed construction and you could run 15" deflectors below with no ceiling. Chris Cahill, P.E. Fire Protection Engineer Sentry Fire Protection, Inc. 763-658-4483 763-658-4921 fax Email: [email protected] Mail: P.O. Box 69 Waverly, MN 55390 Location: 4439 Hwy 12 SW Waverly, MN 55390 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Russell Sent: Wednesday, March 10, 2010 2:16 PM To: AFSA Subject: Concealed spaces I need some facts or opinions. Mine doesn't seem to count any longer. I have 2x9 solid wood floor joist (150 year old historical building) that I'm attaching gypsum board to the bottom in order to eliminate having to sprinkler a concealed combustible space. The architect is asking me if the gypsum board needs a fire rating and do the joints need to be mudded. I say yes to both but he needs more than my opinion. Can you help, please? Russell Rewis Brown Automatic Sprinklers, Inc. 107C Hemlock Street Valdosta, Georgia 31601 229-244-8130 [email protected] _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
