Residential Sprinkler System Design sy Residential Sprinkler...Residential Sprinkler System Design • In 2006, 66 percent of fire deaths and more than 25 percent of firefighter on-duty

Residential Sprinkler System Design

• In2006,66percentoffiredeathsandmorethan25percentoffirefighteron-dutydeathsoccurredinone-andtwo-familydwellings.1

• Theavailabletimetoescapeaflamingfireinahomehasbeenreducedsignificantly,fromanaverageof17minutesin1975toasfewasthreeminutesin2003.2Modernfurnishingsburnfast,andsmokealarmsnolongermaysoundintimeforoccupantstoescape.

• Lightweightconstructionendangersoccupantsandfirefighters.Sprinklersprotectlightweightconstruction.

• Whenbothfiresprinklersandsmokealarmsarepresentinahome,theriskofdyinginafireisreducedby82percentwhencomparedtoaresidencewithouteither.3

• Inalmost2,000fireincidentsinhomesprotectedwithfiresprinklers,nofire-relateddeathswerereportedduringthe2002–2005period.3

By Marshall A. Klein, PE, and Julius Ballanco, PE

Made Easy

Why are residential sprinklers such a big issue?

12 PlumbingSystems&Design SEPTEMBER 2008 PSDMAGAZINE.ORG

Majorresistancetorequiringresidentialsprinklersinnewhomesbycodeofficialsinthepasthasincludedthefollowingconcerns.• Sprinklerinstallationneedstobeenforcedbythecodeoffi-

cialthroughtheInternationalResidentialCode(IRC),andtheofficialshouldbeabletofindsuchrequirementsintheIRC.Theofficialshouldnotneedtolooktoanothercodeorstandardtofindtheappropriaterequirements.TheintentoftheIRC,aswellasitspredecessor,theCABOOne-andTwo-familyDwellingCode,istohaveoneself-contained,stand-alonecodebookthathasalltheprescriptiverequirementsforthebuildingofahomethatboththehomebuilderandthecodeofficialcanuseforthedesign,review,construction,andinspectionofthehome.

• Thesprinklersystemmustbeclearandsimpleenoughtobedesignedandinstalledbyahomeownerbuildinghisownhome.Inmanypartsofthecountry,homeownersdesiretodothegreatmajorityofworkinbuildingtheirhome,sorequirementsintheIRCshouldattempttoaccommodatetothemaximumextentpossibletheneedsofthesehomeown-ersthroughsimplicityofhomebuildingrequirements.

• Thesprinklerdesignandinstallationshouldbepermittedtobeeitherastand-alonesprinklersystemoramultipurposepipingsystem(servingboththedomesticwaterandsprin-klersystem)thatthehomeownerbuilderorplumbercaninstall.Iftheobjectivesofthefirsttwoconcernsabovearemet,thereisnoreasonnottopermitthehomeownerbuilderortheplumberfromfollowingthecoderequirementsandinstallingthesprinklersinone-andtwo-familydwellings.BoththeInternationalPlumbingCodeandtheUniformPlumbingCodepermitmultipurposepipingsystems,wherethesprinklersystemisapartoftheplumbingsystem.Ofcourse,ifonedesirestocontractwithasprinklerinstallerforthedesignandinstallationofthesprinklersystem,thatpres-entsnoproblemsunderthecode.

What has changed this year?Foundedin2007,theIRCFireSprinklerCoalitionhasgrown

toincludemorethan80international,national,andregionalsupportingorganizations,includingfireandcodeofficialgroupsin38states,allofwhomsupporttheinstallationofresidentialfiresprinklersystemsinnewhomes.ThemissionoftheCoali-tionistopromotethehealth,safety,andwelfareofthepublicandemergencyrespondersbysupportingtheinstallationoffiresprinklersinresidentialoccupancies.Moreinformationcanbefoundatwww.ircfiresprinkler.org.

Establishedin1873,theInternationalAssociationofFireChiefs(IAFC)representstheleadershipofmorethan1.2millionfirefighters.IAFCmembersaretheworld’sleadingexpertsinfirefighting,emergencymedicalservices,terrorismresponse,hazardousmaterialspills,naturaldisasters,searchandrescue,andpublicsafetylegislation.Moreinformationcanbefoundatwww.iafc.org.

ForthelatestIRCcodecycleforthenexteditionoftheIRC(2009),theIAFCjointlyworkedwiththeIRCFireSprinklerCoalitiontodraftanIRCCodeProposaltoaddresstheaboveconcernsofthecodeofficials.IRCCodeProposalRP3-07/08wassubmittedandpublishedbytheInternationalCodeCouncil(ICC)initsCodeProposalMonographinNovember2007,andtestimonywasheardbeforetheIRCPlumbingandMechanical

SEPTEMBER 2008 PlumbingSystems&Design 13

CodeDevelopmentCommitteeonFebruary21,2008,attheICCCodeDevelopmentHearingsinPalmSprings,California.TheIRCPlumbingandMechanicalCodeDevelopmentCommitteevotedtorecommendapprovalofthiscodeproposaltotheIRCmembership.Thefinalvoteonitsadoptionintothe2009IRCwillbeconductedinSeptemberduringtheICCAnnualConferenceattheFinalActionHearinginMinneapolis.

CodeProposalRP3-07/08providesasimple,prescriptive,andcost-effectiveapproachtoresidentialfiresprinklersystemsthatisfullycontainedintheIRC.Thistextwillallowacontractororhomebuildertoinstallaresidentialsprinklersystemwithoutreferencinganothercodeorstandard.TherequirementsareintendedtobefullyconsistentwithNationalFireProtectionAssociation(NFPA)13D:Standard for the Installation of Sprin-kler Systems in One- and Two-family Dwellings and Manufac-tured Homes,buttheyaresimplified.Homebuildersstillhavetheoptionofusingthenationallyrecognizedstandard,NFPA13D,whichallowsanengineereddesignoptionandotherpipingcon-figurations.Theapproachofincludingprescriptivetablesinthe

IRC,butstillpermittinganengineereddesignalternativebasedonrecognizedstandards,isalogical,reasonablewaytohandleresidentialsprinklerrequirements.

AfundamentalassumptionofRP3-07/08isthatthepipingwillcomplywithalloftherequirementsapplicabletoaresidentialplumbingsystemestablishedbyIRC.AnotherfundamentalassumptionofRP3-07/08isthatthedesignerandinstallerwillmakeuseofmanufacturerinstructionsforsprinklersandsprin-klerpipeandthattheinstructionswillincludeallofthebasicrequirementsnecessarytodesignandinstallthesecomponents.

Themostnotableaspectoftheproposedsectionisthetabularapproachtodealingwithhydraulicdesign.Inanefforttosim-plifythedesignofresidentialsprinklersystems,comprehensivepipesizingtableshavebeenprovided,addressingelevationlossandallsourcesofpressurelossinasystemasabasisforprescribingamaximumpipelengthbetweenthewatersupplyandthemostremotesprinkler.Thetablesaccommodatevarious

sizesforundergroundandabovegroundpipinganddifferentmetersizes.

Thecostofresidentialsprinklersystemsusingthemethodproposedrangesfrom$0.050persquarefootto$1.75persquarefoot.Ofcourse,pricingwillvarythroughoutthecountrybasedonmaterialandlaborcosts.Thetypicalinstallationwillbeclosertothemiddleorhigherendofthepricerangeratherthanthelowerend.

Forcoordinationpurposes,thesameprescriptivedesignmethodandtablesweresubmittedtotheNFPA13DCommitteeforinclusioninthenexteditionofNFPA13D(2009).CodePro-posalNFPA13D-54wouldaddanewSection8.4.10:“Prescrip-tionPipeSizingMethod”andthesameprescriptivetablesaswereproposedfortheIRC.TheNFPA13DCommitteereviewedthisproposalatitsROPMeetingandapprovedit.Thisproposalandtherecommendationofapprovedwerepublishedforpubliccommentinthecommittee’sJune2009ReportonProposals.ThedeadlineforpubliccommentstoNFPA13DwasAugust29,2008.Sincethisarticlewhentopressbeforethepubliccomment

deadlineforNFPA13D,wedonotknowifanypubliccommentsweresentintoNFPAconcerningCodePro-posalNFPA13D-54.

irc rp3-07/08: prescriptive pipe sizing MethodThefollowingproposed,germanetextonthepre-

scriptivepipesizingcomesfromIRCCodeProposalRP3-07/08.ThisnewtextisundertheproposedSectionP2904:“DwellingFireSprinklerSystems.”

P2904.1 General. Whereinstalled,residentialfiresprinklersystems,orportionsthereof,shallbeinaccor-dancewithNFPA13DorSectionP2904,whichshallbeconsideredequivalenttoNFPA13D.SectionP2904shallapplytostand-aloneandmultipurposewet-pipesprin-klersystemsthatdonotincludetheuseofantifreeze.Amultipurposefiresprinklersystemshallprovidedomesticwatertobothfiresprinklersandplumbingfix-tures.Astand-alonesprinklersystemshallbeseparateandindependentfromthewaterdistributionsystem.Abackflowflowpreventershallnotberequiredtoseparateastand-alonesprinklersystemfromthewater

distributionsystem.P2904.6.2 Prescriptive pipe sizing method. Pipeshallbe

sizedbydeterminingtheavailablepressuretooffsetfrictionlossinpipingandidentifyingapipingmaterial,diameter,andlengthusingtheequationinSectionP2904.6.2.1andtheprocedureinSectionP2904.6.2.2.

P2904.6.2.1 Available pressure equation. Thepressureavail-abletooffsetfrictionlossintheinteriorpipingsystem(Pt)shallbedeterminedinaccordancewithEquation29-1:

Pt=Psup–PLsvc–PLm–PLd–PLe–Psp

where Pt= PressureusedinapplyingTablesP2904.6.2(4)through

P2904.6.2(9) Psup= PressureavailablefromthewatersupplysourcePLsvc=Pressurelossinthewaterservicepipe PLm= Pressurelossinthewatermeter PLd= Pressurelossfromdevicesotherthanthewatermeter PLe= Pressurelossassociatedwithchangesinelevation Psp =Maximumpressurerequiredbyasprinkler

PSDMAGAZINE.ORG14 PlumbingSystems&Design SEPTEMBER 2008

FEATURE: Residential spRinkleR system design made easy

P2904.6.2.2 Calculation procedure. Deter-minationoftherequiredsizeforwaterdistri-butionpipingshallbeinaccordancewiththefollowingprocedure:

Step 1: Determine Psup. Obtainthestaticsupplypressurethatwillbeavailablefromthewatermainfromthewaterpurveyor,orforanindividualsource,theavailablesupplypressureshallbeinaccordancewithSectionP2904.5.1.

Step 2: Determine PLsvc. UseTableP2904.6.2(1)todeterminethepressurelossinthewaterservicepipebasedontheselectedsizeofthewaterservice.

Step 3: Determine PLm. UseTableP2904.6.2(2)todeterminethepressurelossfromthewatermeterbasedontheselectedwatermetersize.

Step 4: Determine PLd. Determinethepres-surelossfromdevices,otherthanthewatermeter,installedinthepipingsystemsupplyingsprinklers,suchaspressure-reducingvalves,backflowpreventers,watersoften-ers,orwaterfilters.Devicepressurelossesshallbebasedonthedevicemanufacturer’sspecifications.TheflowrateusedtodeterminepressurelossshallbetheratefromSectionP2904.4.2,exceptthat5gallonsperminute(gpm)shallbeaddedwherethedeviceisinstalledinawaterservicepipethatsuppliesmorethanonedwelling.Asanalternativetodeductingpressurelossforadevice,anautomaticbypassvalveshallbeinstalledtodivertflowaroundthedevicewhenasprinkleractivates.

Step 5: Determine PLe. UseTableP2904.6.2(3)todeterminethepressurelossassociatedwithchangesinelevation.Theele-vationusedinapplyingthetableshallbethedifferencebetweentheelevationwherethewatersourcepressurewasmeasuredandtheelevationofthehighestsprinkler.

Step 6: Determine Psp. DeterminethemaximumpressurerequiredbyanyindividualsprinklerbasedontheflowratefromSectionP2904.4.1.Therequiredpressureisprovidedinthesprinklermanufacturer’spublisheddataforthespecificsprin-klermodelbasedontheselectedflowrate.

Step 7: Calculate Pt. UsingEquation29-1,calculatethepres-sureavailabletooffsetfrictionlossinwaterdistributionpipingbetweentheservicevalveandthesprinklers.

Step 8: Determine the maximum allowable pipe length. UseTablesP2904.6.2(4)throughP2904.6.2(9)toselectamaterialandsizeforwaterdistributionpiping.Thepipingmaterialandsizeshallbeacceptableifthedevelopedlengthofpipebetweentheservicevalvethemostremotesprinklerdoesnotexceedthemaximumallowablelengthspecifiedbytheapplicabletable.InterpolationofPtbetweenthetabularvaluesshallbepermitted.

ThemaximumallowablelengthofpipinginTablesP2904.6.2(4)throughP2904.6.2(9)incorporatesanadjustmentforpipefittings,andnoadditionalconsiderationoffrictionlossesassociatedwithpipefittingsshallberequired.

an interactive exerciseThebestwaytounderstandthemethodologyoftheresidential

sprinklersystemprescriptivedesignmethodistoreviewanexampleofitsactualapplication.Tohelpindesigningunderthismethod,threesampleblankworksheetswithsimple,concise

stepshavebeenprovided.Thefirstblankworksheetisforasin-gle-sprinklerdesign,withonesprinklerinthemosthydraulicallyremoteroominthedwelling.Thesecondblankworksheetisforatwo-sprinklerdesign,withaminimumoftwosprinklersinthemosthydraulicallyremoteareaorroominthedwelling.Thethirdblankworksheetisastep-by-stepdescriptionoftheinputinformationneededtousethisprescriptivedesignmethod,includinghowtocalculateandlookuptheoutputresultsinthetables.Foranydwelling’ssprinklerlayout,youmayneedtouseonlyeitherthefirstorsecondworksheetifthedesignunderconsiderationisusingonlyonesprinklerineachroomorareaofthedwelling,orifthedesignunderconsiderationisusingtwoormoresprinklersineachroomorarea.However,ifthereareroomsorareasinadwellingwithbothsinglesprinklersinsomeroomsorareas,andtwoormoresprinklersinotherroomsorareas,thenananalysisunderbothworksheetswouldbeneededtodeterminethemosthydraulicallydemandingpipesizeforthatdwelling.Thisexplanationmayappearquitecomplicated,butasyoucanseefromtheexamplesthatfollow,thelayoutoftheworksheetsmakesthedesignquitestraightforwardandsimpletodo.

Theexampleandcalculationsareforatwo-storydwellingasshownintheresidentialsprinklerlayoutofthefirstandsecondfloors.Theworksheetsforthefirstexampleareforsuchadwell-ingonpublicwater,andtheworksheetsforthesecondexampleareforthesamedwellingonwellwater.Foreachexample,youneededtoanalyzethreehydraulicallyremoteconditions:

1. Thebedroomsidewallsprinklers,sinceonlyonesprinklerwillbeoperating.Theanalysismustconfirmthateachofthesesprinklerswillflowaminimumof16gpmatanendheadpressureof16poundspersquareinch(psi).Thisremotebedroomarea(masterbedroom)isshownonthesecond-floorsprinklerlayoutdrawing.Theanalysisforthisroomasthemosthydraulicallydemandingareaisshownintheworksheetcalled“PublicWaterExample#1(DesignAnalysis#1)”andtheworksheetcalled“WellWaterExample#2(DesignAnalysis#1).”

2. Thetwosidewallsprinklersinthesecondfloorhallwaywouldbethemosthydraulicallydemandingareaonthesecondfloorforatwo-sprinklerdesignanalysisunderthecode.Thisremoteareaisshownonthesecond-floorsprinklerlayout



drawing.Theanalysisforthishallwayasthemosthydrauli-callydemandingareaisintheworksheetcalled“PublicWaterExample#1(DesignAnalysis#2)”andtheworksheetcalled“WellWaterExample#2(DesignAnalysis#2).”

3. Thetwopendentsprinklersinthefirst-floorlivingroomwouldbethemosthydraulicallydemandingareaonthefirstfloorforatwo-sprinklerdesignanalysisunderthecode.Thisremoteareaisshownonthefirst-floorsprinklerlayoutdraw-ing.Theanalysisforthelivingroomasthemosthydraulicallydemandingareaisintheworksheetcalled“PublicWaterExample#1(DesignAnalysis#3)”andtheworksheetcalled“WellWaterExample#2(DesignAnalysis#3).”

Withineachexampleanditsworksheets,theassumptionsmadearenotedandexplained,andthevalueschosenaredirectlyfromthenotedtables.Therelevantspecificationsheetsforthependentandsidewallsprinklersalsoareprovidedwithcalloutsnotingthesprinklerwaterdemandandpressure.

NotethattheP2904tableswereadjustedforadoptionintheIRCorNFPA13Dcodestoworkwithboththesingle-sprinklerandthetwo-sprinklerdesignanalyses.Foratwo-sprinklerdesignanalysis,usethesprinklerflowvalueinthetablesthat

istwotimesthesingle-sprinklerflowforthesprinklerunderanalysis.Also,forthePspforEquation29-1(seeStep6intheworksheets),alwaysusethesprinklerendheadvalueforasinglesprinklerregardlessofwhetherornotitisasingle-ortwo-sprin-klerdesignanalysis.Again,thetablesfortheprescriptivedesignmethodhavebeenadjustedtoworkforboththesingle-andtwo-sprinklerdesigns.

Public WaterAfterreviewingthethreeworksheetsforExample#1(public

water),thefollowingdesignconclusionscanbemade:• Theundergroundwaterservicewillbeaminimumof1inch.

Themetersizeisaminimumof¾inch.TheundergroundpipingmaterialcanbePE,PVC,PEX,orcopperthatmeetstheplumbingcode.

• Sincethemostdemandingsprinklerareaisthesecondfloorhallway,thewaterdistributionpipinginsidethedwellingfeedingthesetwohallwaysidewallsprinklerscanbe1-inchcopper(TypeM),¾-inchor1-inchCPVC,or1-inchPEX.

• Forallotherdistributionpipinginsidethedwellingcomingoffthepipingallowedinthebulletitemdirectlyabove,theotherbedroomsidewallsprinklersonthesecondfloorandallthependentsprinklersonthefirstfloorcanbeservicedfrom¾-inchor1-inchcopper(TypeM),¾-inchor1-inchCPVC,or1-inchPEX.

Well WaterDoingasimilarreviewofthethreeworksheetsforExample#2

(wellwater),thefollowingdesignconclusionscanbemade:• Theundergroundwaterservicewillbeofanysizeandmate-

rialpermittedbytheplumbingcodesincethesprinklersys-tem’sdesignisbasedonthepressuresettingofthepumpattheentranceofthedwelling.

• Foralldistributionpipinginsidethedwelling,allthesprin-klerscanbeservicedfrom¾-inchor1-inchcopper(TypeM),¾-inchor1-inchCPVC,or1-inchPEX.

Thisentireanalysisisdonewiththeuseoftheactualstreetstaticpressure,actuallengthofthewaterservicepipe,manufacturer’sspecificationsheetsfortheparticularsprinklersyoudesiretouse,thepickingofavalue(pressurelossinpsi)outofthenewproposed“lookup”tablesinthecode,takingthosepressurelossvaluestodothesubtractioninEquation29-1,andfinallygoingbacktothelookuptablesinthecodetopickoutthemaximumallowablepipelengthforthetypeofinsidewaterdistributionpipingyoudesiretousetofeedamultipurposesprinkler/domesticsystem(orifyoudesireastand-alonesprin-klersystem).

Theresidentialprescriptivedesignmethodistrulyastraightforward,simple,cookbookdesignmethodthatprovidesthereasonable,conservative,andaffordabledesignandinstallationofsprinklersinresi-dentialdwellings.

For extra creditIfyouareinclinedtodelveintosprinkler

hydraulicsbeyondthecookbookapproachdiscussedhere,gototheIRCFireSprinklerCoalitionwebsite(www.ircfiresprinkler.org).YouwillfindanExcelspreadsheettemplatefreefordownloadingthatdoescalculationsidenticaltothoseinthelookuptables.However,becauseTableP2904.6.2(1):“WaterServicePressureLoss”wassimplifiedforinclusioninthecodestocoverallthecommon,permittedtypesofmaterials(PE,PVC,PEX,andcopper),thattable’spressurelossesarebasedonthemostrestrictivelossesofallthesematerials,whichisPEataSRDvalueof11.

IntheExcelspreadsheettemplatearepull-downinputmenusthatpermitentryoftheactualtype(material)oftheoutsidewaterservicepipinganditsactuallength.Therefore,thefinalvaluesforthemaximumallowablelengthofthepipinginsidethedwellingwillbegreaterthanthelookuptablevalues



(TablesP2904.6.2(4)throughP2904.6.2(9)).ThemorepreciseExcelspreadsheettemplatevaluesmaybehelpfulinsituationswherethe“cookbook”designgetsyouclosetotheinsidepipesizeyoudesire,butbecauseoftheconservativedesignofTableP2904.6.2(1)fortheoutsidewaterservicepiping,theallowableinsidepipelengthisfallingshort.

a step in the right directionIRCCodeProposalRP3-07/08andNFPACodeProposalNFPA

13D-54representamajoradvancementintheefforttomakeresidentialsprinklersystemssimpleandaffordableandserveasabasisforincorporatingaprescriptiveapproachtoresidentialsprinklersystemsinboththe2009editionoftheIRCandthe2009editionofNFPA13D.

reFerences1. Ahrens,Marty.Trends and Patterns of U.S. Fire Losses. NFPA.

2007.2. NISTTechnicalNote1455:Performance of Home Smoke

Alarms.NationalInstituteofStandardsandTechnology.2004.

3. Benefit-Cost Analysis of Residential Fire Sprinkler Systems. NationalInstituteofStandardsandTechnology.2007.

Marshall Klein is president of Marshall A. Klein and Associates Inc., an engineering consulting firm that specializes in national building and fire code issues. He is an active participant in the ICC code change cycles. Julius Ballanco is president of JB Engineering and Code Consulting, a firm specializing in code and standard consulting in the areas of plumbing, mechanical, life safety, and fire protection engineering. For more information or to comment on this article, e-mail [email protected].



TABLE P2904.6.2(2)MINIMUM WATER METER PRESSURE LOSS (PLM)A

FLOW RATE (GPM)B

5/8 inch METERPRESSURE LOSS

(PSI)

3/4 inch METERPRESSURE LOSS

(PSI)

1 inch METERPRESSURE LOSS

(PSI)8 2 1 1

10 3 1 112 4 1 114 5 2 116 7 3 118 9 4 120 11 4 222 NP 5 224 NP 5 226 NP 6 228 NP 6 230 NP 7 232 NP 7 334 NP 8 336 NP 8 3

NP - Not permitted unless the actual water meter pressure loss is known.a. Table 2904.6.2(2) establishes conservative values for water meter pressure loss or

installations where the water meter loss is unknown. Where the actual water meter pressure loss is known, Pm shall be the actual loss.

b. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section P2904.4.2 where the water-service pipe supplies more than one dwelling.

TABLE P2904.6.2(3)ELEVATION LOSS (PLE)

ELEVATION (FEET)

PRESSURE LOSS (PSI)

5 2.210 4.415 6.520 8.725 10.930 1335 15.240 17.4

TABLE P2904.6.2(1)WATER SERVICE PRESSURE LOSS (PLSVC)a, b

(Underlining of table omitted for clarity)

Flow Ratec

(gpm)

¾ inch Water Service Pressure Loss (psi)

1 inch Water Service Pressure Loss (psi)

1¼ inch Pressure Water

Service Loss (psi)

76' to 100'101' to

150' 40' or less

41' to 75'

76' to 100'

101' to

150'40' or less

41' to 75'

76' to 100

101' to

150'40' or less

41' to 75'

8 5.1 8.7 11.8 17.4 1.5 2.5 3.4 5.1 0.6 1.0 1.3 1.910 7.7 13.1 17.8 26.3 2.3 3.8 5.2 7.7 0.8 1.4 2.0 2.912 10.8 18.4 24.9 NP 3.2 5.4 7.3 10.7 1.2 2.0 2.7 4.014 14.4 24.5 NP NP 4.2 7.1 9.6 14.3 1.6 2.7 3.6 5.416 18.4 NP NP NP 5.4 9.1 12.4 18.3 2.0 3.4 4.7 6.918 22.9 NP NP NP 6.7 11.4 15.4 22.7 2.5 4.3 5.8 8.620 27.8 NP NP NP 8.1 13.8 18.7 27.6 3.1 5.2 7.0 10.422 NP NP NP NP 9.7 16.5 22.3 NP 3.7 6.2 8.4 12.424 NP NP NP NP 11.4 19.3 26.2 NP 4.3 7.3 9.9 14.626 NP NP NP NP 13.2 22.4 NP NP 5.0 8.5 11.4 16.928 NP NP NP NP 15.1 25.7 NP NP 5.7 9.7 13.1 19.430 NP NP NP NP 17.2 NP NP NP 6.5 11.0 14.9 22.032 NP NP NP NP 19.4 NP NP NP 7.3 12.4 16.8 24.834 NP NP NP NP 21.7 NP NP NP 8.2 13.9 18.8 NP36 NP NP NP NP 24.1 NP NP NP 9.1 15.4 20.9 NP

NP - Not permitted. Pressure loss exceeds reasonable limitsa. Values are applicable for underground piping materials listed in Table P2904.4 and are based on an SDR of 11 and a Hazen Williams C Factor of 150.b. Values include the following length allowances for fittings: 25% length increase for actual lengths up to 100 feet and 15% length increase for actual lengths

over 100 feet.c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section P2904.4.2 where the water-service pipe supplies more than one dwelling.

TABLE P2904.6.2(4) ALLOWABLE PIPE LENGTH FOR ¾ INCH TYPE M COPPER WATER TUBING(Underlining of table omitted for clarity)

Sprinkler Flow Ratea

(gpm)

Water Distribution Size (inch)

Available Pressure - Pt (psi)15 20 25 30 35 40 45 50 55 60

Allowable Length of Pipe from Service Valve to Farthest Sprinkler (feet)8 3/4 217 289 361 434 506 578 650 723 795 8679 3/4 174 232 291 349 407 465 523 581 639 697

10 3/4 143 191 239 287 335 383 430 478 526 57411 3/4 120 160 200 241 281 321 361 401 441 48112 3/4 102 137 171 205 239 273 307 341 375 41013 3/4 88 118 147 177 206 235 265 294 324 35314 3/4 77 103 128 154 180 205 231 257 282 30815 3/4 68 90 113 136 158 181 203 226 248 27116 3/4 60 80 100 120 140 160 180 200 220 24117 3/4 54 72 90 108 125 143 161 179 197 21518 3/4 48 64 81 97 113 129 145 161 177 19319 3/4 44 58 73 88 102 117 131 146 160 17520 3/4 40 53 66 80 93 106 119 133 146 15921 3/4 36 48 61 73 85 97 109 121 133 14522 3/4 33 44 56 67 78 89 100 111 122 13323 3/4 31 41 51 61 72 82 92 102 113 12324 3/4 28 38 47 57 66 76 85 95 104 11425 3/4 26 35 44 53 61 70 79 88 97 10526 3/4 24 33 41 49 57 65 73 82 90 9827 3/4 23 30 38 46 53 61 69 76 84 9128 3/4 21 28 36 43 50 57 64 71 78 8529 3/4 20 27 33 40 47 53 60 67 73 8030 3/4 19 25 31 38 44 50 56 63 69 7531 3/4 18 24 29 35 41 47 53 59 65 7132 3/4 17 22 28 33 39 44 50 56 61 6733 3/4 16 21 26 32 37 42 47 53 58 6334 3/4 NP 20 25 30 35 40 45 50 55 6035 3/4 NP 19 24 28 33 38 42 47 52 5736 3/4 NP 18 22 27 31 36 40 45 49 5437 3/4 NP 17 21 26 30 34 38 43 47 5138 3/4 NP 16 20 24 28 32 36 40 45 4939 3/4 NP 15 19 23 27 31 35 39 42 4640 3/4 NP NP 18 22 26 29 33 37 40 44

NP - Not permitted a. Flow rate from Section P2904.4.2

TABLE P2904.6.2(5) ALLOWABLE PIPE LENGTH FOR 1 INCH TYPE M COPPER WATER TUBING(Underlining of table omitted for clarity)

Sprinkler FlowRatea

(gpm)

WaterDistribution

Size(inch)


Allowable Length of Pipe from Service Valve to Farthest Sprinkler (feet)8 1 806 1075 1343 1612 1881 2149 2418 2687 2955 32249 1 648 864 1080 1296 1512 1728 1945 2161 2377 2593

10 1 533 711 889 1067 1245 1422 1600 1778 1956 213411 1 447 596 745 894 1043 1192 1341 1491 1640 178912 1 381 508 634 761 888 1015 1142 1269 1396 152313 1 328 438 547 657 766 875 985 1094 1204 131314 1 286 382 477 572 668 763 859 954 1049 114515 1 252 336 420 504 588 672 756 840 924 100816 1 224 298 373 447 522 596 671 745 820 89417 1 200 266 333 400 466 533 600 666 733 79918 1 180 240 300 360 420 479 539 599 659 71919 1 163 217 271 325 380 434 488 542 597 65120 1 148 197 247 296 345 395 444 493 543 59221 1 135 180 225 270 315 360 406 451 496 54122 1 124 165 207 248 289 331 372 413 455 49623 1 114 152 190 228 267 305 343 381 419 45724 1 106 141 176 211 246 282 317 352 387 42225 1 98 131 163 196 228 261 294 326 359 39226 1 91 121 152 182 212 243 273 304 334 36427 1 85 113 142 170 198 226 255 283 311 34028 1 79 106 132 159 185 212 238 265 291 31829 1 74 99 124 149 174 198 223 248 273 29830 1 70 93 116 140 163 186 210 233 256 28031 1 66 88 110 132 153 175 197 219 241 26332 1 62 83 103 124 145 165 186 207 227 24833 1 59 78 98 117 137 156 176 195 215 23434 1 55 74 92 111 129 148 166 185 203 22235 1 53 70 88 105 123 140 158 175 193 21036 1 50 66 83 100 116 133 150 166 183 19937 1 47 63 79 95 111 126 142 158 174 19038 1 45 60 75 90 105 120 135 150 165 18139 1 43 57 72 86 100 115 129 143 158 17240 1 41 55 68 82 96 109 123 137 150 164

a. Flow rate from Section P2904.4.2



TABLE P2904.6.2(6) ALLOWABLE PIPE LENGTH FOR ¾ INCH CPVC PIPE(Underling of table omitted for clarity)

Sprinkler Flow

Ratea(gpm)

WaterDistribution

Size(inch)



10 3/4 231 307 384 461 538 615 692 769 845 92211 3/4 193 258 322 387 451 515 580 644 709 77312 3/4 165 219 274 329 384 439 494 549 603 65813 3/4 142 189 237 284 331 378 426 473 520 56814 3/4 124 165 206 247 289 330 371 412 454 49515 3/4 109 145 182 218 254 290 327 363 399 43616 3/4 97 129 161 193 226 258 290 322 354 38717 3/4 86 115 144 173 202 230 259 288 317 34618 3/4 78 104 130 155 181 207 233 259 285 31119 3/4 70 94 117 141 164 188 211 234 258 28120 3/4 64 85 107 128 149 171 192 213 235 25621 3/4 58 78 97 117 136 156 175 195 214 23422 3/4 54 71 89 107 125 143 161 179 197 21423 3/4 49 66 82 99 115 132 148 165 181 19824 3/4 46 61 76 91 107 122 137 152 167 18325 3/4 42 56 71 85 99 113 127 141 155 16926 3/4 39 52 66 79 92 105 118 131 144 15727 3/4 37 49 61 73 86 98 110 122 135 14728 3/4 34 46 57 69 80 92 103 114 126 13729 3/4 32 43 54 64 75 86 96 107 118 12930 3/4 30 40 50 60 70 81 91 101 111 12131 3/4 28 38 47 57 66 76 85 95 104 11432 3/4 27 36 45 54 63 71 80 89 98 10733 3/4 25 34 42 51 59 68 76 84 93 10134 3/4 24 32 40 48 56 64 72 80 88 9635 3/4 23 30 38 45 53 61 68 76 83 9136 3/4 22 29 36 43 50 57 65 72 79 8637 3/4 20 27 34 41 48 55 61 68 75 8238 3/4 20 26 33 39 46 52 59 65 72 7839 3/4 19 25 31 37 43 50 56 62 68 7440 3/4 18 24 30 35 41 47 53 59 65 71


TABLE P2904.6.2(7) ALLOWABLE PIPE LENGTH FOR 1 INCH CPVC PIPE(Underlining of table omitted for clarity)

SprinklerFlow Ratea

(gpm)

WaterDistribution

Size(inch)



10 1 694 925 1157 1388 1619 1851 2082 2314 2545 277611 1 582 776 970 1164 1358 1552 1746 1940 2133 232712 1 495 660 826 991 1156 1321 1486 1651 1816 198113 1 427 570 712 854 997 1139 1281 1424 1566 170914 1 372 497 621 745 869 993 1117 1241 1366 149015 1 328 437 546 656 765 874 983 1093 1202 131116 1 291 388 485 582 679 776 873 970 1067 116417 1 260 347 433 520 607 693 780 867 954 104018 1 234 312 390 468 546 624 702 780 858 93619 1 212 282 353 423 494 565 635 706 776 84720 1 193 257 321 385 449 513 578 642 706 77021 1 176 235 293 352 410 469 528 586 645 70422 1 161 215 269 323 377 430 484 538 592 64623 1 149 198 248 297 347 396 446 496 545 59524 1 137 183 229 275 321 366 412 458 504 55025 1 127 170 212 255 297 340 382 425 467 51026 1 118 158 197 237 276 316 355 395 434 47427 1 111 147 184 221 258 295 332 368 405 44228 1 103 138 172 207 241 275 310 344 379 41329 1 97 129 161 194 226 258 290 323 355 38730 1 91 121 152 182 212 242 273 303 333 36431 1 86 114 143 171 200 228 257 285 314 34232 1 81 108 134 161 188 215 242 269 296 32333 1 76 102 127 152 178 203 229 254 280 30534 1 72 96 120 144 168 192 216 240 265 28935 1 68 91 114 137 160 182 205 228 251 27336 1 65 87 108 130 151 173 195 216 238 26037 1 62 82 103 123 144 165 185 206 226 24738 1 59 78 98 117 137 157 176 196 215 23539 1 56 75 93 112 131 149 168 187 205 22440 1 53 71 89 107 125 142 160 178 196 214


TABLE P2904.6.2(8) ALLOWABLE PIPE LENGTH FOR ¾ INCH PEX TUBING(Underlining of table omitted for clarity)


(gpm)




10 3/4 61 82 102 123 143 163 184 204 225 24511 3/4 51 68 86 103 120 137 154 171 188 20512 3/4 44 58 73 87 102 117 131 146 160 17513 3/4 38 50 63 75 88 101 113 126 138 15114 3/4 33 44 55 66 77 88 99 110 121 13215 3/4 29 39 48 58 68 77 87 96 106 11616 3/4 26 34 43 51 60 68 77 86 94 10317 3/4 23 31 38 46 54 61 69 77 84 9218 3/4 21 28 34 41 48 55 62 69 76 8319 3/4 19 25 31 37 44 50 56 62 69 7520 3/4 17 23 28 34 40 45 51 57 62 6821 3/4 16 21 26 31 36 41 47 52 57 6222 3/4 NP 19 24 28 33 38 43 47 52 5723 3/4 NP 17 22 26 31 35 39 44 48 5224 3/4 NP 16 20 24 28 32 36 40 44 4925 3/4 NP NP 19 22 26 30 34 37 41 4526 3/4 NP NP 17 21 24 28 31 35 38 4227 3/4 NP NP 16 20 23 26 29 33 36 3928 3/4 NP NP 15 18 21 24 27 30 33 3629 3/4 NP NP NP 17 20 23 26 28 31 3430 3/4 NP NP NP 16 19 21 24 27 29 3231 3/4 NP NP NP 15 18 20 23 25 28 3032 3/4 NP NP NP NP 17 19 21 24 26 2833 3/4 NP NP NP NP 16 18 20 22 25 2734 3/4 NP NP NP NP NP 17 19 21 23 2535 3/4 NP NP NP NP NP 16 18 20 22 2436 3/4 NP NP NP NP NP 15 17 19 21 2337 3/4 NP NP NP NP NP NP 16 18 20 2238 3/4 NP NP NP NP NP NP 16 17 19 2139 3/4 NP NP NP NP NP NP NP 16 18 2040 3/4 NP NP NP NP NP NP NP 16 17 19

NP - Not permitted. a. Flow rate from Section P2904.4.2.

TABLE P2904.6.2(9) ALLOWABLE PIPE LENGTH FOR 1 INCH PEX TUBING(Underlining of table omitted for clarity)


(gpm)




10 1 208 277 346 415 485 554 623 692 761 83111 1 174 232 290 348 406 464 522 580 638 69612 1 148 198 247 296 346 395 445 494 543 59313 1 128 170 213 256 298 341 383 426 469 51114 1 111 149 186 223 260 297 334 371 409 44615 1 98 131 163 196 229 262 294 327 360 39216 1 87 116 145 174 203 232 261 290 319 34817 1 78 104 130 156 182 208 233 259 285 31118 1 70 93 117 140 163 187 210 233 257 28019 1 63 84 106 127 148 169 190 211 232 25320 1 58 77 96 115 134 154 173 192 211 23021 1 53 70 88 105 123 140 158 175 193 21122 1 48 64 80 97 113 129 145 161 177 19323 1 44 59 74 89 104 119 133 148 163 17824 1 41 55 69 82 96 110 123 137 151 16425 1 38 51 64 76 89 102 114 127 140 15226 1 35 47 59 71 83 95 106 118 130 14227 1 33 44 55 66 77 88 99 110 121 13228 1 31 41 52 62 72 82 93 103 113 12429 1 29 39 48 58 68 77 87 97 106 11630 1 27 36 45 54 63 73 82 91 100 10931 1 26 34 43 51 60 68 77 85 94 10232 1 24 32 40 48 56 64 72 80 89 9733 1 23 30 38 46 53 61 68 76 84 9134 1 22 29 36 43 50 58 65 72 79 8635 1 20 27 34 41 48 55 61 68 75 8236 1 19 26 32 39 45 52 58 65 71 7837 1 18 25 31 37 43 49 55 62 68 7438 1 18 23 29 35 41 47 53 59 64 7039 1 17 22 28 33 39 45 50 56 61 6740 1 16 21 27 32 37 43 48 53 59 64

a. Flow rate from Section P2904.4.2.



Blank Worksheet #1: Single-sprinkler Design

Pt= Psup - PLsvc - PLd - PLe - Psp (Available Pressure Equation 29-1)

Sing

le S

prin

kler

Des

ign

____

__ g

pm

Columns A B C D E F Steps Determine Use Psup

Value Total

Pressure Losses Value

Pt Value Maximum Allowable

Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 2 PLsvc Table P2904.6.2(1) 3 PLm Table P2904.6.2(2) + 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) + 5 PLe Table P2904.6.2(3) + 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Single sprinkler design is = _____ gpm

+

7a

Pt

Sum the Pressure Losses in Column D Column D = (PLsvc + PLm + PLd + PLe + Psp)

Column D

=

7b Subtract: (Value in Column C/Step 1) - (Value in Column D @Step 7a)

Pt=

8 Maximum Allowable Pipe

Length

Table P2904.6.2(4) for ¾” Cu Type M Table P2904.6.2(5) for 1” Cu Type M Table P2904.6.2(6) for ¾” CPVC Table P2904.6.2(7) for 1” CPVC Table P2904.6.2(8) for ¾” PEX Table P2904.6.2(9) for 1” PEX

Blank Worksheet #2: Two-sprinkler Design


Tw

o Sp

rink

lers

Des

ign

____

__ g

pm


Value Total



Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 2 PLsvc Table P2904.6.2(1) 3 PLm Table P2904.6.2(2) + 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) + 5 PLe Table P2904.6.2(3) + 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Two sprinklers design is = _____ gpm

+

7a

Pt

Sum the Pressure Losses in Column D: Column D = (PLsvc + PLm + PLd + PLe + Psp)

Column D

=


Pt=

8 Maximum Allowable Pipe

Length

Table P2904.6.2(4) for ¾” Cu Type M Table P2904.6.2(5) for 1” Cu Type M Table P2904.6.2(6) for ¾” CPVC Table P2904.6.2(7) for 1” CPVC Table P2904.6.2(8) for ¾” PEX Table P2904.6.2(9) for 1” PEX



Blank Worksheet #3: Step-by-Step Description of Input Information


Inputs for Steps: 1. Public Water Supply/ Well Water Supply Psup= ___ psi 2. Water Service Flow Rate (Taken from input Step #6) = _____ gpm ¾”/ 1”/ 1¼” Water Service, Actual Length of Water Service = _____feet

Table Lookup Length 40’/ 41’- 75’/ 76’- 100’/ 101’- 150’ Pick value from Table P2904.6.2(1) PLsvc= ___ psi

3. Water Meter Pressure Loss Based on Flow Rate for Input for Step #2 and 5/8”/ ¾”/ 1” Meter Pick value from Table P2904.6.2(2) PLm= ___ psi 4. Additional pressure losses from other devices taken from Manufacturers’ specifications for such devices: a. Type of device:___________________= ________psi loss b. Type of device:___________________= ________psi loss c. Type of device:___________________= ________psi loss

PLd= ___ psi [which is the (“a” through “c”) of all the above devices] 5. Elevation between water service and highest sprinkler =_______feet x 0.433 = PLe = _________psi loss (or pick value from Table

P2904.6.2(3)) 6. From Manufacturer’s Sprinkler Specifications and the maximum spacing used for the sprinklers in your layout, the Sprinkler Flow Rate is ____

gpm for a single sprinkler, or is _____ gpm for two sprinklers, at a minimum required pressure (Psp) of ________psi Outputs for Steps: 7a. The first part of Step 7 to determine Pt is to add up all the pressure losses in Column D from Steps 2 through 6:

Sum of the pressure losses = _____ psi 7b. The second (and last) part of Step 7 to determine Pt is to then subtract Psup (The value in Column C of Step 1) from the sum of the pressure

losses in Step 7a (Value in Column D @Step 7a): Pt = (Value in Step #1) minus (Value in Step #7a) = _____ psi

8. Maximum Allowable Pipe Length for the water distribution piping inside the building is looked up in Tables P2904.6.2(4) through P2904.6.2(9)

based on the Single Sprinkler Flow Rate ( __ gpm) or the Two Sprinklers Flow Rate ( ___ gpm) from Step #6, the available pressure calculated in Step #7 (Pt= ___ psi), the piping material (Cu Type M, CPVC or PEX) and its pipe diameter (3/4” or 1”).



Public Water Example #1 (Design Analysis #1) Given for Examples #1: Two story house as shown on public water with a static supply pressure at the street connection of 55 psi. Using Viking sidewall sprinklers (Model VK453) on the 2nd floor, and Viking pendent sprinklers (Model VK435) on the 1st floor. Underground is a minimum 1” water service with a ¾” meter, 50’ in length. Please note that a 1” water service is used since a preliminary review of the house’s floor plans and preliminary sprinkler layout shows that we will need to perform, as one of the minimum designs, a two sprinkler flow design on both the 1st and 2nd floors. We know that the best minimum flow for the low flow sprinklers on the market today is 8 gpm/sprinkler. Therefore, if we need a minimum 2 sprinkler design the minimum flow through the underground water service would be 16 (2 x 8) gpm. In addition, in our case where a single sprinkler design with a sidewall sprinkler is going to be used on the second floor, we know that for the Viking Model VK453 at the minimum spacing of 16’ x16’ required for this sprinkler layout, we need a minimum of 16 gpm per Viking’s specs. Reviewing Table P2904.6.2, a pressure loss for any water flow > 14 gpm flow rate in a 3/4” water service between 41’ and 75’ in length, is not permitted (NP). Therefore, we then need to increase the water service to a minimum of 1” to obtain a pressure loss value in Table P2904.6.2 for a 50’ run of underground when over 14 gpm sprinkler demand is flowing through the underground pipe.


Sing

le S

prin

kler

Des

ign

for

2nd F

loor

Mas

ter

Bed

room

16

gpm


Value Total



Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 55 2 PLsvc Table P2904.6.2(1) (1” service loss for 41’-75’ flowing 16 gpm) 9.1 3 PLm Table P2904.6.2(2) (3/4” meter flowing 16 gpm) +3.0 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) +0.0 5 PLe Table P2904.6.2(3) (Vertical Elevation Loss from street is 20’) +8.7 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Single sprinkler design is = 16 gpm (Master Bedroom is 14’-8” x 11’, therefore use the minimum 16’ x 16’ spacing for minimum flow and pressure for the Viking Model VK453 sidewall sprinkler specs)

+16.0

7a

Pt


Column D

=36.8


Pt=18.2 (Use 15)

8 Maximum Allowable Pipe Length > Actual

Inside Water Pipe Length of

28’ horizontal + 20’ vertical =

48’

Table P2904.6.2(4) for ¾” Cu Type M 60’ OK Table P2904.6.2(5) for 1” Cu Type M 224’ OK Table P2904.6.2(6) for ¾” CPVC 97’ OK Table P2904.6.2(7) for 1” CPVC 291’ OK Table P2904.6.2(8) for ¾” PEX 26’ NO

GOOD Table P2904.6.2(9) for 1” PEX 87’ OK

Public Water Example #1 (Design Analysis #2)


Tw

o Sp

rink

lers

Des

ign

for

2nd F

loor

Hal

lway

22

gpm


Value Total



Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 55 2 PLsvc Table P2904.6.2(1) (1” service loss for 41’-75’ flowing 22 gpm) 16.5 3 PLm Table P2904.6.2(2) (3/4” meter flowing 22 gpm) +5.0 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) +0.0 5 PLe Table P2904.6.2(3) (Vertical Elevation Loss from street is 20’) +8.7 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Two sprinklers design is = 22 gpm (The Hallway space is “t” shaped, about 8’ x 8’ (& its hallway width is 3’). However, the sprinkler at the top of the stairs in the hallway also protects the top three steps of the stairs that can not be covered by the sidewall sprinkler that is located in the hallway outside the bathroom. Therefore,. to be conservative use the minimum 12’ x 12’ spacing for minimum flow for 2 sprinklers and minimum pressure for one sprinkler flowing using the Viking Model VK453 sidewall sprinkler specs)

+7.6

7a

Pt


Column D

=37.8


Pt=17.2 (Use 15)

8 Maximum Allowable Pipe Length> Actual



44’

Table P2904.6.2(4) for ¾” Cu Type M 33’ NO GOOD

Table P2904.6.2(5) for 1” Cu Type M 124’ OK Table P2904.6.2(6) for ¾” CPVC 54’ OK Table P2904.6.2(7) for 1” CPVC 161’ OK Table P2904.6.2(8) for ¾” PEX NP: NO




Public Water Example #1 (Design Analysis #3)


Tw

o Sp

rink

lers

Des

ign

for

1st F

loor

Liv

ing

Roo

m

20 g

pm


Value Total



Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 55 2 PLsvc Table P2904.6.2(1) (1” service loss for 41’-75’ flowing 20 gpm) 13.8 3 PLm Table P2904.6.2(2) (3/4” meter flowing 20 gpm +4.0 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) +0.0 5 PLe Table P2904.6.2(3) (Vertical Elevation Loss from street is 10’) +4.4 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Two sprinklers design is = 20 gpm (The Living Room space is 12’ x 18’ x 1” but the Kitchen/Dining is a minimum 12’-1” wide so to be conservative use the minimum 14’ x 14’ spacing for minimum flow for 2 sprinklers and minimum pressure for one sprinkler flowing using the Viking Model VK435 pendent sprinkler specs)

+10.4

7a

Pt


Column D

=32.6


Pt=22.4 (Use 20)




41’



Well Water Example #2 (Design Analysis #1)

Given for Examples #2: Two story house as shown on private well water with the well pump’s pressure at the building’s entrance set at a minimum 45 psi. Using Viking sidewall sprinklers (Model VK453) on the 2nd floor, and Viking pendent sprinklers (Model VK435) on the 1st floor. Because the pump pressure setting is at the building’s entrance there is no need to calculate PLsvc and there is no meter loss (PLd).

Pt= Psup - PLe - Psp (Available Pressure Equation 29-1 adjusted for Private Well Design)

Sing

le S

prin

kler

Des

ign

for

2nd F

loor

Mas

ter

Bed

room

16

gpm


Value Total



Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 45 2 PLsvc Table P2904.6.2(1) N/A 3 PLm Table P2904.6.2(2) +N/A 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) +0.0 5 PLe Table P2904.6.2(3) (Vertical Elevation Loss from street is 20’) +8.7 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Single sprinkler design is = 16 gpm (Master Bedroom is 14’-8” x 11’, therefore use the minimum 16’ x 16’ spacing for minimum flow and pressure for the Viking Model VK453 sidewall sprinkler specs)

+16.0

7a

Pt


Column D

=24.7


Pt=20.3 (Use 20)

8 Maximum Allowable Pipe Length > Actual



48’





Well Water Example #2 (Design Analysis #2)

Pt= Psup - PLe - Psp (Available Pressure Equation 29-1 adjusted for Private Well Design)

Tw

o Sp

rink

lers

Des

ign

for

2nd F

loor

Hal

lway

22

gpm

Columns A B C D E F

Steps Determine Use Psup Value

Total Pressure Losses Value


Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 45 2 PLsvc Table P2904.6.2(1)) N/A 3 PLm Table P2904.6.2(2) +N/A 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) +0.0 5 PLe Table P2904.6.2(3) (Vertical Elevation Loss from street is 20’) +8.7 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Two sprinklers design is = 22 gpm (The Hallway space is “t” shaped, about 8’ x 8’ (& its hallway width is 3’). However, the sprinkler at the top of the stairs in the hallway also protects the top three steps of the stairs that can not be covered by the sidewall sprinkler that is located in the hallway outside the bathroom. Therefore,. to be conservative use the minimum 12’ x 12’ spacing for minimum flow for 2 sprinklers and minimum pressure for one sprinkler flowing using the Viking Model VK453 sidewall sprinkler specs)

+7.6

7a

Pt


Column D

=16.3


Pt=28.7 (Use 25)




44’



Well Water Example #2 (Design Analysis #3) Pt= Psup - PLe - Psp (Available Pressure Equation 29-1 adjusted for Private Well Design)

Tw

o Sp

rink

lers

Des

ign

for

1st F

loor

Liv

ing

Roo

m

20 g

pm


Value Total



Pipe Length

1 Psup Sec. P2904.5.1: Pressure available from the water source 45 2 PLsvc Table P2904.6.2(1)) N/A 3 PLm Table P2904.6.2(2) +N/A 4 PLd Sec. P2904.4.2 (Manufacturer’s Specs. on devices) +0.0 5 PLe Table P2904.6.2(3) (Vertical Elevation Loss from street is 10’) +4.4 6 Psp Sec. P2904.4.1 (Manufacturer’s Specs. on sprinkler being used)

From the Manufacturer’s Specs the Flow Rate for the Two sprinklers design is = 20 gpm (The Living Room space is 12’ x 18’ x 1” but the Kitchen/Dining is a minimum 12’-1” wide so to be conservative use the minimum 14’ x 14’ spacing for minimum flow for 2 sprinklers and minimum pressure for one sprinkler flowing using the Viking Model VK35 pendent sprinkler specs)

+10.4

7a

Pt


Column D

=14.8


Pt=30.2 (Use 30)




41’





Residential Sprinkler Layout for Examples #1 (Public Water) & #2 (Well System) Under the Prescriptive Sprinkler Design Method

Water service entrance

Hydraulically remote area for two sprinkler design for first floor. See Worksheet Examples #1-3 (Public Water) & #2-3 (Well Water)

Jeffrey

Text Box

This drawing has been revised from the originally published article to improve clarity and correct an error

Hydraulically remote area for two sprinkler design for 2nd floor. See Worksheet Examples #1-2 (Public Water) & #2-2 (Well Water)

Hydraulically remote area for single sprinkler design for 2nd floor. See Worksheet Examples #1-1 (Public Water) & #2-1 (Well Water)

Jeffrey

Text Box

This drawing has been revised from the originally published article to improve clarity and correct an error

Sidewall sprinklers will be used on the 2nd floor.

Need to use minimum 12’ x 12’ design criteria for the two sidewall sprinklers protecting the 2nd floor hallway.

Need to use minimum16’ x 16’ design criteria for the single sidewall sprinklers protecting the 2nd floor bedrooms.



Pendent sprinklers will be used on the 1st floor.

Need to use minimum 14’ x 14’ design criteria for the two hydraulically remote sprinklers protecting the 1st floor Living Room.



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