Just an adder to what Ken said. The 3000sf design area has to be used in all adjacent areas, so if the area above the TJI's is occupied that to must be designed with 3000sf. Pretty much if you see TJI's anywhere you have a 3000sf design area.
Thom McMahon, SET Firetech, Inc. 2560 Copper Ridge Dr P.O. Box 882136 Steamboat Springs, CO 80488 Tel: 970-879-7952 Fax: 970-879-7926 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Parsley Consulting Sent: Saturday, May 16, 2009 8:08 PM To: [email protected] Subject: Re: 24" TJI Wood Joist Phil, In the annex of the 2007 edition is something that might help: A.8.5.4.1 Batt insulation creates an effective thermal barrier and can be considered the ceiling/roof deck when determining distances between deflector and ceiling. The insulation needs to be installed in each pocket (not just above the sprinkler) and attached to the ceiling/roof in such a manner that it will not fall out during a fire prior to sprinkler activation Based on this, if you had three inches of batt insulation, at the top of the joist channel, it could be regarded as the effective "deck" above the sprinkler deflector, which could then be located 1" down from the bottom of the CWJ, and remain 22" down from the face of the insulation. Additionally, it's a possible solution would be to provide a layer of non- or limited-combustible materials on the bottom of the composite wood joists, forming a non-sprinklered combustible concealed space above. The caveat there is that it forces the remote area below to increase to 3,000 square feet. You do get to reduce the density, but you still have to calculate 3,000 square feet. Those are some thoughts on what you can do. PARSLEY CONSULTING Ken Wagoner, SET 760.745.6181 voice 760.745.0537 fax [email protected] <mailto:[email protected]> e-mail www.ParsleyConsulting.com <http://www.ParsleyConsulting.com> website Phil Nawrocki wrote: > Sirs, > > We have a contract to install fire sprinklers in a building with 24" > deep TJI composite wood joist construction. They are 24" on center. > I can find nothing in NFPA #13 deflector rules that allow the > sprinkler deflector under obstructed construction to be below 22" from > the deck. Is there any other way to protect the area besides putting > a sprinkler in each 24" wide joist space? > > Regards, > > Phillip H. Nawrocki > Design Manager > National Fire Sprinkler, Inc. > 1544 W. Grant St. > Phoenix, AZ 85007-3314 > (602) 712-1180 Phone Ext #33 > (602) 712-1260 Fax > [email protected] > Fire Sprinklers Save Lives! > > > > _______________________________________________ > 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) _______________________________________________ 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)
