Do the last two posts reflect divergent opinions by two #13 committee members? I thought it was all B&W.....
Seriously, if you have time to approach the AHJ (and make time, obviously, rather than risk your dwgs bounced...) and point out that if 4" wide continous grilles were added about the perimeter, then it would no longer be a floating ceiling, and it would be a (noncombustible) concealed space. Then ask "what changes if the grilles are removed, from a thermodynamic perspective?" If your AHJ can handle that question intelligently, you may then have permission to omit protection above, and the taxpayers don't need to pay for the grilles. I believe this would assist in merging the two trains of thought in the previous posts by Misters Huggins and Caputo- and I would highly recommend not disregarding the opinions of either one of these learned members of #13 Committee: 1. RJH is also on the Standards Council 2. BC is a VP of your firm. glc -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Tuesday, August 05, 2008 10:31 AM To: [email protected] Subject: RE: Floating Ceilings The floating ceiling question is commonly asked during live seminars... if the ceiling is floating and not attached (connected to; touching) the walls, the area above the ceiling is required to be protected regardless of the type or combustibility of construction. Bob Caputo ---- [EMAIL PROTECTED] wrote: > The presence of a return air plenum doesn't automatically necessitate sprinklers. Sprinklers are going to be required in the space if combustibles with ratings equal to or above that which is allowed for a concealed space are present as defined in NFPA 13. > > If it is a plenum it may actually be beneficial from a fire protection standpoint in that the utilities within that plenum have to be specifically rated for such use, thus minimizing their risk for fire and smoke spread. This may result in no need for sprinklers in the plenum space. > > You could put in 2x2 or 4x4 free return (without ductwork) grilles into the ceiling for that matter and it wouldn't change the combustible nature of the space above the ceiling. Also the HVAC units will or should have smoke detection to sense any smoke present from the return air. Unit smoke detection of course will depend on the size of the air handlers. > > > > > > > Craig L. Prahl, CET > Fire Protection Group > Mechanical Department > CH2MHILL > Lockwood Greene > 1500 International Drive > PO Box 491, Spartanburg, SC 29304-0491 > Direct - 864.599.4102 > Fax - 864.599.8439 > [EMAIL PROTECTED] > http://www.ch2m.com > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Fletcher, Ron > Sent: Tuesday, August 05, 2008 9:59 AM > To: [email protected] > Subject: RE: Floating Ceilings > > You can have an unlimited number 2'x4' return air grills in the ceiling without adding sprinklers above but put a 4" wide slot around edge of the room and sprinklers are required. Go figure. > > Where do you get "a plenum thus requiring sprinklers"? > > Ron Fletcher > Aero Automatic Sprinkler > Phoenix, AZ > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Maag, Barry > Sent: Tuesday, August 05, 2008 6:08 AM > To: [email protected] > Subject: RE: Floating Ceilings > > I have seen these types in the past and the "space" around the floating ceiling was used for the return air for HVAC. This made the area above the ceiling a plenum thus requiring sprinklers > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Rick Green > Sent: Tuesday, August 05, 2008 7:59 AM > To: [email protected] > Subject: Floating Ceilings > > > I am in the design phase installing wet pipe sprinkler systems protecting new schools. > > I have noticed that in several of the rooms in the schools(cafeteria, band room, main corridor that runs the length of the school), architect has designed lay-in ceiling systems with gaps ranging from 4" to 12" > along the walls and between sections of ceiling within the rooms (floating ceiling sections). > > I do not believe my non-combustible concealed space above the ceilings is concealed anymore and may require protection. > > Has anyone dealt with this? > > I have heard some discussion that if the total square feet of the openings is below a certain percent of the total square foot of a space, sprinkler protection above the space may not be required? > > Interesting thing is that the school is being built as a "Green" project and seems like the designed openings would make the schools less energy efficient. > > Anyone's help would be most appreciated... > > > > Rick E. Green > District Manager > East Coast Fire Protection, Inc. > 1113 Cavalier Boulevard > Chesapeake, Virginia 23323 > 757/485-7486(p), 757/295-0956(direct), 757/328-0131(cell) [EMAIL PROTECTED] > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > To Unsubscribe, send an email > to:[EMAIL PROTECTED] > (Put the word unsubscribe in the subject field) > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > To Unsubscribe, send an email to:[EMAIL PROTECTED] > (Put the word unsubscribe in the subject field) > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > To Unsubscribe, send an email to:[EMAIL PROTECTED] > (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
