So if the joisting is wood, but encapsulated by 5/8 type X GWB then the assembly is still considered combustible? What if enough layers (three I think) to get a 2-hr rating?
On Mon, Aug 5, 2013 at 11:32 AM, Roland Huggins <[email protected]>wrote: > Granted as pointed out that everything else must also be non- or > limited-combustible but it's a moot point since it is WOOD JOIST > construction. Focusing on the outer membrane doesn't change the fact that > the assembly is combustible construction. > > Roland > > > Roland Huggins, PE - VP Engineering > American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives > Dallas, TX > http://www.firesprinkler.org > > > > > > On Aug 5, 2013, at 7:26 AM, Brian Harris <[email protected]> > wrote: > > > All- > > I recently finished a design for a wood structure day care facility, (1) > level of attic heads and (1) level of ceiling heads. The GC has now decided > in an effort to save money on the HVAC to attach drywall to the bottom of > the wood joist and use the area between this drywall and the suspended > ceiling as a return air plenum. If I'm reading 8.1.1.2.1 & 8.15.1.2.2 > correctly I do not need to add a 3rd level of protection in this "plenum" > area correct? > > > > Brian Harris, CET > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 [email protected] http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC, WFSC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
