How I see this, when the distance between sprinklers varies, the more demanding distance is what drives the required minimum discharge pressure. The shorter distance gets over discharged but the longer distance gets the application called for in the design. So these sprinklers need to be pressurized for 110 sf operational area, not 100 sf. I think you are in trouble if there is a 100 sf limitation imposed somewhere that is not countered and accepted by using a hydraulic design for 110 sf per sprinkler.
A somewhat similar, but perhaps more defendable, condition to this occurs when two rooms each having 130 sf/sprinkler designs, but as 10 x 13 in one room and 13 x 10 in the other room, have the dividing wall between the rooms removed. The design in each room worked on its own, including up to its wall, but now the design is technically 11.5 x 13 where the wall used to be. It is defendable when one considers each sprinkler as having its own operational area, but that concept is not normally accepted and has been shot down here without discussion. Allan Seidel > On Jan 18, 2022, at 10:50 AM, Kyle.Montgomery via Sprinklerforum > <sprinklerforum@lists.firesprinkler.org> wrote: > > Matt, > > I haven't dealt with that situation in real life, but have in theory had > several conversations about it. I am in agreement with you that this should > be allowable per the code language. You never exceed 110 s.f. and the average > ACTUAL FLOOR AREA (not SxL) does not exceed 100 s.f. > > -Kyle M > > -----Original Message----- > From: Sprinklerforum <sprinklerforum-boun...@lists.firesprinkler.org> On > Behalf Of Matt Grise via Sprinklerforum > Sent: Tuesday, January 18, 2022 8:22 AM > To: sprinklerforum@lists.firesprinkler.org > Cc: Matt Grise <m...@afpsprink.com> > Subject: [EXTERNAL] RE: ESFR obstruction shift > > No - since we are moving along the line, when one space goes from 10 to 11, > the space on the other side goes from 10' to 9' > > Matt > > > -----Original Message----- > From: Sprinklerforum <sprinklerforum-boun...@lists.firesprinkler.org> On > Behalf Of Matthew J Willis via Sprinklerforum > Sent: Tuesday, January 18, 2022 9:00 AM > To: sprinklerforum@lists.firesprinkler.org > Cc: Matthew J Willis <ma...@rapidfireinc.com> > Subject: RE: ESFR obstruction shift > > Are you not creating a 10x11 situation since you are moving every other > sprinkler? > > If so, you may be violating the 100 sq ft per average requirement for moved > and adjacent? > > R/ > Matt > > -----Original Message----- > From: Sprinklerforum <sprinklerforum-boun...@lists.firesprinkler.org> On > Behalf Of Matt Grise via Sprinklerforum > Sent: Tuesday, January 18, 2022 6:00 AM > To: sprinklerforum@lists.firesprinkler.org > Cc: Matt Grise <m...@afpsprink.com> > Subject: ESFR obstruction shift > > I am looking at a warehouse layout where we can get a very nice head pattern > by laying the heads out 10ft by 10ft, and then shifting the ones that land > near joists 1ft along the line as allowed by NFPA 13. > > The only issue is that we have to shift every other head. Making a 9ft - 11ft > pattern along the branch line. As far as I can tell, this meets the letter of > the code, but it seems like a stretch. > > Has anyone come across a similar situation where so many heads needed to be > shifted to avoid roof structures? > > Matt > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > https://urldefense.com/v3/__https://linkprotect.cudasvc.com/url?a=http*3a*2f*2flists.firesprinkler.org*2flistinfo.cgi*2fsprinklerforum-firesprinkler.org&c=E,1,l1exGGqk0cDcPNoSdqRWtD1YmZdqStCzx0CUF-Olhi1rqB9Iz8Fn6d7eBTNXNMfF8T-7GZY94qom2OweTyV4Gyin1hiL-CJ82tDF4yhwF7g0ofhpr4fwsNalRZM,&typo=1__;JSUlJSU!!Ba8_KKAT!eogk1pEssHmJtaZHhoNM1xMOrahW4a40OEoiC7xHQPIDjpwV0fnvj8Sfjpv8d1bFGzI$ > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > https://urldefense.com/v3/__https://linkprotect.cudasvc.com/url?a=http*3a*2f*2flists.firesprinkler.org*2flistinfo.cgi*2fsprinklerforum-firesprinkler.org&c=E,1,faagUYTvRqNofSbZjC709kxTbRDQVTelhUkbtQ0AWq4V349KeRLZVnCRia1Vjt6yQqBjB_beLshOylNEy-3N0UIJJJFKTWvWeUpRcWUx-0A,&typo=1__;JSUlJSU!!Ba8_KKAT!eogk1pEssHmJtaZHhoNM1xMOrahW4a40OEoiC7xHQPIDjpwV0fnvj8Sfjpv8sH-n2sk$ > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > https://urldefense.com/v3/__http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org__;!!Ba8_KKAT!eogk1pEssHmJtaZHhoNM1xMOrahW4a40OEoiC7xHQPIDjpwV0fnvj8Sfjpv8Su2SCv4$ > > _______________________________________________ > 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
