Bobby, I would treat it as obstructed construction with your sprinklers located 1-6in below the bottom of the joists. You wouldn't need sprinklers in each pocket if the insulation wasn't there so I do not see why you would need additional sprinklers with the insulation. Now if the ceiling is installed within 6in from the bottom of the wood joists, you can omit the sprinklers in the combustible concealed space entirely per 8.15.1.2.5. Just my take on it.... Dewayne
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bobby Gillett Sent: Thursday, October 16, 2008 8:32 AM To: [email protected] Subject: Combust. Concealed Space I am working on a two story building with a dry system. First floor ceiling is 2x4 ACT @ 8'-0 hung from the bottom of the 2x12 joists. There is mesh netting at the bottom of the joists supporting the insulation. There is plywood decking at the top of the joists used as subfloor for second floor. The 2x12 joists are on 16" centers. I'm waiting for the answer on the thickness of the insulation. If I'm reading correctly, NFPA 2007 8.15.1.2.16 allows me to not sprinkle the area between the ceiling and bottom of joists if there are sprinklers above the insulation. But being these are joists and not trusses that creates many, many sprinklers. Is there anything that would allow sprinkling below the insulation and not above? I have asked the GC for proposed thickness of insulation and the possibility of raising the insulation to the bottom of deck so there would only be one space. I don't have a reply as of yet. Bobby Gillett SR.Project Manager [EMAIL PROTECTED] (731) 424-0130 office (731) 267-4853 cell _______________________________________________ Sprinklerforum mailing list http://lists.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 http://lists.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)
