Good point John. Here is where the decision process has to be made. If you cannot keep the builder or architect from installing this type of ceiling, then consideration needs to be made as to what is the sprinkler system going to protect and how will it protect it properly. I just finished having an architect redesign his slat ceiling to accommodate the sprinkler system. Essentially, these slats were 2 X 12s hanging from the deck but the distance apart was much less than 12 inches. I told him that we could not tolerate this type of ceiling in a sprinklered building. He did a remarkable thing. He sculptured the boards such that one was lesser width along side ones of full width. Then he modeled the sprinkler spray pattern to indicate that, to the sprinkler, the boards seemed thinner and that the spray pattern was not disrupted and that most of the pattern did reach the floor. We had more than 3 feet to deck from the top of the boards. At the concepts stage for the new San Antonio, TX courthouse, there was a slat ceiling design. I was able to get ahead of the architectural design and I am going to insure that we don't have this problem again because it is so difficult to make these work properly unless some research is done with full scale testing to see what is proper coverage.
* * *Thanks* * * *Rahe Loftin, PE * *Fire Protection Engineer (AHJ)* *General Services Administration* *Region 7 - TX, OK, NM, AR, LA* *Design & Construction 7PCE* * * *c - 817-371-3102* *o - 817-978-7299* On Fri, May 10, 2013 at 9:23 AM, John Denhardt <jdenha...@stricklandfire.com > wrote: > Rahe - What about the exposed wood on the top? > > John August Denhardt, P.E., FSFPE > Strickland Fire Protection Incorporated > 5113 Berwyn Road > College Park, Maryland 20740 > Office Telephone Number: 301-474-1136 > Mobile Telephone Number: 301-343-1457 > FIRE SPRINKLERS SAVE LIVES - Can you live without them? > > > -----Original Message----- > From: sprinklerforum-boun...@lists.firesprinkler.org [mailto: > sprinklerforum-boun...@lists.firesprinkler.org] On Behalf Of Rahe Loftin > - 7PCE > Sent: Friday, May 10, 2013 10:24 AM > To: SprinklerFORUM > Subject: Re: Slatted Wood Ceilings > > Brian, > Please look at the NFPA 13, 2013 Edition excerpt below. The things to note > is that the depth of the ceiling material does not exceed the least > dimension of the opening. Some will interpret this section that it only > applies to egg crate ceiling designs, Look at the Annex note following the > code excerpt. Note that it includes louver ceilings. This is what you > have. The slated ceiling is a louver ceiling in context with this NFPA 13 > section. > > The real problem you are facing is that, if the depth exceeds the opening > width, this ceiling cannot be installed as proper sprinkler protection will > not be afforded. The first statement in this section says that open grid > ceilings shall only be installed beneath sprinklers where one of the > following conditions exist, i.e. width depth ratio is met. > > 8.15.14* Open-Grid Ceilings. > Open-grid ceilings shall only be installed beneath sprinklers where one of > the following is > met: > > (1) Open-grid ceilings in which the openings are 1⁄4 in. (6.4 mm) or larger > in the least dimension, > *where the thickness or depth of the material does not exceed the least > dimension* > *of the opening*, and where such openings constitute 70 percent of the area > of the ceiling > material. The spacing of the sprinklers over the open-grid ceiling shall > then comply with > the following: > > (a) In light hazard occupancies where sprinkler spacing (either spray or > old-style sprinklers) > is less than 10 ft 10 ft (3 m 3 m), a minimum clearance of at least 18 > in. > (457 mm) shall be provided between the sprinkler deflectors and the upper > surface > of the open-grid ceiling. Where spacing is greater than 10 ft 10 ft (3 m > 3 m) but > less than 10 ft 12 ft (3 m 3.7 m), a clearance of at least 24 in. (610 > mm) shall be > provided from spray sprinklers and at least 36 in. (914 mm) from old-style > sprinklers. > Where spacing is greater than 10 ft 12 ft (3 m 3.7 m), a clearance of > at least 48 in. > (1219 mm) shall be provided. > > (b) In ordinary hazard occupancies, open-grid ceilings shall be permitted > to be installed > beneath spray sprinklers only. Where sprinkler spacing is less than 10 ft > 10 ft (3 m > 3 m), a minimum clearance of at least 24 in. (610 mm) shall be provided > between > the sprinkler deflectors and the upper surface of the open-grid ceiling. > Where spacing > is greater than 10 ft 10 ft (3 m 3 m), a clearance of at least 36 in. > (914 mm) shall > be provided. > > (2) Other types of open-grid ceilings shall be permitted to be installed > beneath sprinklers > where they are listed for such service and are installed in accordance with > instructions > contained in each package of ceiling material. > > A.8.15.14 The installation of open-grid egg crate, *louver*, or honeycomb > ceilings beneath > sprinklers restricts the sideways travel of the sprinkler discharge and can > change the character > of discharge. > > > > * > * > *Thanks* > * > * > *Rahe Loftin, PE * > *Fire Protection Engineer (AHJ)* > *General Services Administration* > *Region 7 - TX, OK, NM, AR, LA* > *Design & Construction 7PCE* > * > * > *c - 817-371-3102* > *o - 817-978-7299* > > > On Fri, May 10, 2013 at 8:25 AM, Brian Harris <bhar...@bvssystemsinc.com > >wrote: > > > All- > > Working on a project that has a suspended slatted wood ceiling in the > > lobby. The ceiling is made up of 4" wide wood strips with ½" gap in > between > > each slat, I originally intended to have heads above and below the > ceiling > > but now I'm wondering if the heads at the deck are required. Thoughts? > > > > Brian Harris, CET > > BVS Systems Inc. > > Sprinkler Division > > bvssystemsinc.com<http://bvssystemsinc.com/> > > Phone: 704.896.9989 > > Fax: 704.896.1935 > > > > _______________________________________________ > > Sprinklerforum mailing list > > Sprinklerforum@lists.firesprinkler.org > > > > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
