I guess my explanation was not very clear. The peak is 16 feet above the floor, but 3 feet above the ceiling. The ceiling slopes with the roof, as the drywall is attached to the bottom of the truss. Yours and Ed's replies confirm my thoughts. The ceiling height in this case would be 3 feet, allowing the 40% reduction.
Tony -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Parsley Consulting Sent: January 27, 2008 4:25 PM To: [email protected] Subject: Re: Sloped combustible ceiling space Tony, I think you're headed in the right direction, but I'd check the math on the reduction you get using the greatest height in a sloped ceiling area. If the roof peak is 16' above the ceiling the reduction would be less than if the maximum ceiling height was 10'-0" or less. If there is a ceiling on the bottom of the truss, then the height of the space from the ceiling to the peak is the governing value for the reduction for quick response sprinklers. If the peak (highest elevation) of the roof is 16'-0" above the ceiling then the reduction for quick response sprinkler is more or less 465 square feet, with the resulting remote area minimum being 1,035 square feet. An increase of 30% for a sloped ceiling greater than 2:12 would bring the remote area minimum to 1,345, more or less. -- *Ken Wagoner, SET* *Parsley Consulting* *760.745.6181 voice* *760.745.0537 fax* *www.parsleyconsulting.com <http://www.parsleyconsulting.com/>* * * A.P.Silva wrote: > I'm reviewing a design for a wet system in a sloped combustible > ceiling space. The 12:3 sloped roof is supported on wood trusses. > There is drywall at the bottom of the wood trusses and the insulation > is on the roof. The roof peak is about 16 feet high. There is a wet > sprinkler system in the ceiling space with sprinklers above and below > the ceiling. Due to compartmentation below the ceiling, the most > demanding system would be that above the ceiling. I'm trying to > determine the design area. All sprinklers are QR. When using the area > reduction for using QR heads, would the ceiling height be the height > of the wood trusses (roof deck above and drywall below)? The height of > the ceiling space is about 3 feet. If I select 1500 sf design area, > increase 30% for slope (1950 sf) and reduce 40% for QR (1170 > sf) is it correct? My question is, is the ceiling height, the height > of the ceiling space, qualifying for the maximum 40% reduction. I > think it is, but thought I'll throw it at this forum. > > Tony > > _______________________________________________ > 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)
