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System Report
APA Simplified Wall Bracing Method Using Wood Structural Panel Continuous Sheathing1. Basis of the system RepoRt
n 2012InternationalResidentialCode(IRC):SectionsR104.11AlternativeMaterials,DesignandMethodsof
ConstructionandEquipment,R301.1.3EngineeredDesign,andR602.12SimplifiedWallBracing
n 2012AWCWoodFrameConstructionManualforOneandTwoFamilyDwellings(WFCM)
n APAReportsT2011L-33,T2012L-16,T2012L-30andothertestdata
2. system DescRiption
TheSimplifiedWallBracingMethoddescribedinthisreportprovidesbuildingofficials,buildersanddesignerswith
anapproachandthesupportingtechnicalinformationtomeettherequirementsofthe2012IRCSimplifiedWall
Bracing(SectionR601.12).Inthedevelopmentofthisreport,the2012IRCSimplifiedWallBracinghasbeenmodified
toincreaseitsapplicabilitytoagreaterpercentageofhomedesigns.Toachievebroadapplicabilityandacceptance,
thesystemusesthemostcommontypeofwallsheathing,woodstructuralpanels,basedontheirsuperiorstructural
performance.Toprovidetheuserwiththegreatestpossiblearchitecturallatitude,thissystemreportonlycoverscon-
tinuouslysheathedwoodstructuralpanelbracing(2012IRCMethodCS-WSP)withanincreasedsheathingthickness
(called“PerformanceCategory”inproductstandards)andaclosernailingscheduleonthefirststoryofatwo-story
structure.Thisapproachincreasestheperformanceofthebracingpanelsonthefirststoryduetotheadditionalrestraint
providedbythemassandstiffnessofthestructureabove,throughstrengthfromincreasedfasteningandwiththeuse
ofthickerwoodstructuralpanelcontinuoussheathing.Thisenhancedperformanceonthebottomstoryoftwo-story
structuresleadstoreducedlengthofrequiredbracingintheseareas,allowingforthemethodtobeusedonhomes
withabundantwindowanddooropeningsonthefrontandbackelevations.Thesedecreasesintherequiredbracing
forthebottomstoryofatwo-storystructureareshowninTable3.
Additionalminimumbracedwallpanellengthinformationtakenfromthe2012IRCSectionR602.10hasbeenadded
tothisAPASimplifiedWallBracingMethod.Whilethisaddssomelevelofcomplexityoverthe2012IRCmethod,it
greatlyincreasestheusabilityofthemethod.
Designsimplificationandflexibilityareachievedthroughtheenhancedsheathingthicknessandnailingdescribed
inthisreport.Intermittentwoodstructuralpanel(MethodWSP)andotherbracingmethods,exceptasspecifiedin
Section3.1,areoutsidethescopeofthisreport.LiketheIRCsimplifiedbracingmethod,theAPASimplifiedWall
BracingMethodshallbepermittedforhouseslocatedinareasoflowwindandseismicity.Toincreasetheusabilityof
themethod,thisreportincludesanumberofadditionaldetailstoaugmenttheIRCsimplifiedbracingprovisions.Also
includedarereferencestospecificareasoftheIRCandotherpublicationswhenadditionalinformationisrequired.
Buildingsmeetingtherequirementsofthisreportmeetallofthebracingrequirementsofthe2012IRCSectionR602.10
WallBracingwiththeenhancementsdiscussedinSection3ofthisreport.
sR-102B feBRuaRy 2013
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3. methoDology
3.1 ApplicabilityResidentialstructuresmustmeetallofthefollowingconditionswhenusingthismethod:
1) Theentirebuildingshallbecontinuouslysheathedwithwoodstructuralpanelsinaccordancewiththe
requirementsspecifiedinthissection.
2) Otherbracingprovisionsofthe2012IRCSectionR602.12,exceptasspecifiedherein,areoutsidethescope
ofthismethod.
3) Thefoundationorbasementwallshallbeconcreteormasonry,orconcreteslab;andthestructureabove
shallbe2storiesorless.
4) Floorcantileversshallbenomorethan24inchesbeyondthefoundationorbearingwallbelow.
5) Studwallheightshallbe10feetorlesswhenusingtheminimumrequiredbracinglengthsspecifiedin
Table3ofthisreportunlessadjustmentsaremadeforotherwallheightsupto12feetinaccordancewith
FootnotectoTable3ofthisreport.
6) Roofeave-to-ridgeheightshallbe15feetorless.
7) Interiorfinishofexteriorwallsshallconsistofminimum1/2-inchgypsumboardsinstalledontheinterior
sidefastenedinaccordancewiththe2012IRCTableR702.3.5.Interiorgypsumfinishisnotrequiredon
continuouslysheathedwoodstructuralpanelsadjacenttogarageopenings(MethodCS-G)andcontinuously
sheathedportalframe(MethodCS-PF)bracingpanels(seeSection3.5ofthisreport).
8) Basicwindspeedshallbe100mphorlessandtheWindExposureCategoryshallbeBorC.
9) SeismicDesignCategoryshallbeA,BorCfordetachedone-andtwo-familydwellingsorSeismicDesign
CategoryAorBfortownhouses.
10) Cripplewalls,ifpresent,shallbeconsideredthefirststoryofthepermittedtwostorieswhenusing
thismethod.
3.2 Circumscribed RectangleThebuildingshallbecircumscribedasshowninFigure1.Therectangleshallsurroundallenclosedoffsetsandprojec-
tions,suchassunroomsandattachedgarages,unlessanattachedgarageorportionofthebuildingistobedesigned
asaseparatestructureinaccordancewiththe2012IRCSectionR301.1.3oraseparateelementinaccordancewith
AppendixAofthisreport.Openstructures,suchascarportsanddecks,shallbepermittedtobeexcluded.Therect-
angleshallhavenosidelongerthan60feetandtheratiobetweenthelongsideandtheshortsideshallnotexceed3:1.
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FIGURE 1
Rectangle ciRcumscRibing an enclosed building
3.3 Wood Structural Panel Sheathing MaterialsThewoodstructuralpanelsheathingshallbeRatedSheathingwithaminimum7/16PerformanceCategory,meeting
therequirementsofDOCPS1orPS2.
3.4 Wood Structural Panel Sheathing AttachmentThewoodstructuralpanelsheathingshallbeattachedtoframinginaccordancewiththefollowingrequirements:
1) Thesheathingshallbeinstalledwithminimum8dcommonnails(0.131x2-1/2inches)spacedat4inches
oncenteratpaneledgesandat12inchesoncenteroverintermediatesupports.Forsingle-storyorthetop
storyoftwo-storybuildings,thesheathingmaybeinstalledwith8dcommonnails(0.131x2-1/2inches)
spacedat6inchesoncenteratpaneledgesand12inchesatintermediatesupports.
2) Thesheathingshallbeappliedcontinuouslyoverallareasoftheexteriorwallsexceptwindowsanddoors,
andincludinggableends;andshallbeinstalledeitherverticallyorhorizontally.
3) Allhorizontalpaneljointsshalloccuroverandbenailedtocommonframingorblockingwithanappropri-
atepaneledge-nailingscheduleinaccordancewiththe2012IRCSectionR602.10.10.
4) A24-inchreturncorner,asdefinedinthe2012IRCSectionR602.10.7,shallbelocatedattheendofeach
braced wall lineasdefinedinthe2012IRCSectionR602.10.1.An800-lbfhold-downattachedtotheend
studofthebracedwallpanelclosesttothecornershallbepermittedforuseonbothadjacentwallsinlieu
ofthe24-inchreturncorner.
Long side
Typical wallcorner
Typical segments of wall between corner
Circumscribingrectangle
FIRST FLOOR PLAN
Shor
t sid
e Typical segments of wall between corner
Circumscribingrectangle
SECOND FLOOR PLAN
Long side
Shor
t sid
e
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3.5 “Qualified” Bracing PanelAsingle“qualified”bracingpanelshallconsistofafull-heightportionofanexteriorwallcontinuouslysheathedwith
woodstructuralpanelswithaminimumlengthasshowninTables1and2ofthisreport.Thebracingpanelshallhave
noopenings,exceptthatsmalldrilledholesinthewallsheathingandnotpenetratingthewallframingupto1-1/2inches
forthepassageofwiringandutilitiesshallbepermitted.WhenusingnarrowwallbracingmethodsCS-GandCS-PF,
theminimumpermissiblelengthsandcontributinglengthsforcomputingavailablebracingshallbeasshowninTable
1ofthisreport.WhenusingMethodCS-WSP,Table1providestheminimumpermissiblelengthsandcontributing
lengthsbasedbothonthewallheightandtheadjacentclearopeningheight.Ifan8-or9-foottallwalllineispresent,
MethodCS-WSPbracedwallsegmentslessthantheTable1minimumlengthmaybeusedbutwithacorresponding
reductionincontributinglengthsforcomputingavailablebracinginaccordancewithTable2ofthisreport.
TABLE 1
minimum lengtH oF bRaced Wall Panels (exceRPt FRom tHe 2012 iRc table R602.10.5, modiFied in accoRdance WitH R602.12.3, item 1)
method
minimum length (in.)
contributing length (in.)
Wall Height
8 ft 9 ft 10 ft
CS-G 24 27 30 Actual Length(a)
CS-PF 16 18 20 1.5 x Actual Length(a)
CS-WSP
Adjacent clear opening height (in.)
≤60 24 27 30
Actual Length(a)
64 24 27 30
68 26 27 30
72 27 27 30
76 30 29 30
80 32 30 30
84 35 32 32
88 36 35 33
92 36 36 35
96 36 36 36
100 36 36
104 36 36
108 36 36
112 36
116 36
120 36(a) Use the actual length when it is greater than or equal to the minimum length.
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3.5.1 Partial Credit for CS-WSP PanelsCS-WSPpanelsin8-or9-foottallwallsbetween20and24inchesinlengththatdonotmeettheminimumlength
requirementsofTable1shallbepermittedforuseasbracingunitsatafullorreducedcontributinglength(depending
ontheadjacentopeningheight),asshowninTable2ofthisreportbasedonthelatestAPAresearchresults,asdocu-
mentedinAPAReportsT2012L-16andT2012L-30.
3.6 Computing “Qualified” Wall Bracing LengthWithinanexteriorwall,onlythosefull-heightwallpanelswithalengthgreaterthanorequaltothelengthsspecified
inTables1and2ofthisreportshallbedeemedtocontributetoresistinglateralload,andcountedtowardtherequired
bracinglength.Thetotalbracinglengthalongthesideofarectangleisequaltothesumofthecontributinglengths
ofeach“qualified”wallpanel.Anylengthofa“qualified”bracingpanelovertheminimumbracinglengthrequired
inTable1ofthisreportshallbepermittedforusetowardthetotalbracinglengthrequiredforthatwall.Thus,ifthe
minimumrequirementforaspecificmethodis24inchesinaccordancewithTable1ofthisreportandtwosuchpanels
withlengthsof26and34inchesarepresent,(26+34=)60inchesor(60/12=)5feetofbracingarepresentandshall
bepermittedforuseindeterminingthetotalbracinglengthforthatwall.
ForMethodsCS-GandCS-PF,thebracinglengthoneithersideoftheopeningisconsidereda“qualified”bracing
panelandcontributestobracinglengthsformeetingtheminimumlengthrequirementsofTable1ofthisreport.An
exampleisprovidedinAppendixB.
TABLE 2
PaRtial cRedit FoR cs-WsP less tHan Full lengtH WitH 8- and 9-Foot tall Walls(a)
Wall Height (ft)
length of Full Height method cs-WsP Panel
(in.)
adjacent to a clear opening Height
(in.) or less
contributing length of braced Wall Panel
(in.)
8 or 9
24
≤60 24
64 22
68 20
72 18
76 16
80 14
20
≤60 20
64 18
68 16
72 15
76 13
80 11
(a) Linear interpolation shall be permitted
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3.7 Length of Bracing RequiredDeterminingthebracinglengthrequiredisrelativelystraightforward:
1) Circumscribethebuildingwitharectangle.Therectangleshallenclosethemaximumbuildinglengthand
widthdimensionsasdescribedinSection3.2.
2) Ensurethatthelongsideoftherectangleisnotgreaterthan3timestheshortsideoftherectangle.Ifitis
greater,considerusingthemultiplerectanglemethodcoveredinAppendixA.Thealternativesareto:
• n usethe“legacy”bracingprovisionsofthe2012IRCSectionR602.10,
• n usethemultiplerectanglemethodinconjunctionwiththeAPASimplifiedWallBracingMethod
(seeAppendixA),or
• n havethestructuredesignedinaccordancewiththe2012IRCSectionR301.1.3andtheInternational
BuildingCode(IBC).
3) Withthedimensionsofthiscircumscribedrectangle,useTable3ofthisreporttodeterminethebracing
lengththatisrequiredoneachwallperpendiculartothesideusedtoenterthetable.Notethatinterpola-
tionshallbepermitted.Eithervalue,theroundedorinterpolatedvalue,shallbemultipliedbyawallheight
adjustmentfactorinaccordancewithFootnotes(c)and(d)toTable3ofthisreport,asapplicable.
3.8 “Distribution Rules” for Bracing PanelsOncetherequiredbracinglengthhasbeendeterminedforeachsideofthecircumscribedrectangleusingTable3of
thisreport,thisbracinglengthshallbedistributedalongtheactualexteriorwallsofthestructure.Indistributingthese
bracingpanels,allofthefollowing“DistributionRules”shallbemet:
1) Thefirst“qualified”bracingpaneloneachsideoftherectangleshallbeginwithin12feetofthewall
corner.The12feetismeasuredbetweenthewallcornerandclosestedgeofthefirstfull-height“qualified”
bracingpanel.
2) Thedistancebetweentheclosestedgesofadjacentfull-height“qualified”bracingpanelsshallbe20feet
orless.
3) Anywallwithalengthof8feetorgreatershallhaveataminimumof3feetofbracing.
Insomecases,agreaterbracinglengthisrequiredtomeettheDistributionRulesthanisrequiredbyTable3.Inthis
case,thegreaterbracinglengthrequiredbytheDistributionRulesshallgovern.Inanycases,thebracinglengthrequired
byTable3ortheDistributionRules,whicheverisgreater,shallbemet.
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TABLE 3
minimum ReQuiRed bRacing lengtH on eacH side oF tHe ciRcumscRibed Rectangle FoR Wind exPosuRe b(a)(b)(c)(d)
Wind speed
story level
eave-to Ridge Height
(ft)
minimum Required bracing length on each long side
minimum Required bracing length on each short side
length of short side (ft) length of long side (ft)
10 20 30 40 50 60 10 20 30 40 50 60
90
102.0 3.5 5.0 6.0 7.5 9.0 2.0 3.5 5.0 6.0 7.5 9.0
(e) 2.9 5.4 7.4 9.9 12.0 14.0 2.9 5.4 7.4 9.9 12.0 14.0
152.6 4.6 6.5 7.8 9.8 11.7 2.6 4.6 6.5 7.8 9.8 11.7
(e) 3.3 6.2 8.6 11.4 13.8 16.2 3.3 6.2 8.6 11.4 13.8 16.2
100
102.5 4.0 6.0 7.5 9.5 11.0 2.5 4.0 6.0 7.5 9.5 11.0
(e) 3.7 6.6 9.1 12.0 14.9 17.5 3.7 6.6 9.1 12.0 14.9 17.5
153.3 5.2 7.8 9.8 12.4 14.3 3.3 5.2 7.8 9.8 12.4 14.3
(e) 4.3 7.6 10.5 13.8 17.1 20.1 4.3 7.6 10.5 13.8 17.1 20.1
For SI: 1 ft = 304.8 mm
(a) Based on the 2012 IRC Table R602.10.3(1) and modified for the first story of a two story structure in accordance with the latest APA research results, as documented in APA Report T2011L-33.
(b) Interpolation shall be permitted.
(c) The Wall Height Adjustment Factor, as shown below, shall be used to multiply the minimum bracing lengths listed in the table above to accommodate wall heights from 8 to 12 feet based on the 2012 IRC Table R602.10.3(2). Interpolation shall be permitted.
Any Story
Wall Height (ft) Wall Height adjustment Factor
8
9
10
11
12
0.90
0.95
1.00
1.05
1.10
(d) For Wind Exposure Category C, multiply length required from table above by 1.2 for single-story buildings and 1.3 for two-story buildings.
(e) The first of two stories shall be continuously sheathed with wood structural panels attached with 8d common nails (0.131 x 2-1/2 inches) spaced 4 inches on center around the panel perimeter and at 12 inches on center over intermediate supports.
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4. lateRal suppoRt
Forbracingpanelsinexteriorwallslocatedalongeaves,theverticaldistancebetweenthetopplateandtheunderside
oftheroofsheathingshallbe9-1/4inchesorlessatbracingpanellocations.Forverticaldistancesgreaterthan9-1/4
inches,theAPASimplifiedWallBracingMethodshallstillbepermittedforuseprovidingtheattachmentdetailsof
the2012IRCSectionR602.10.8.2aremet.Thesedetailsarenotduplicatedherebecausethelimitationof9-1/4inches
isnotcommonlyexceeded.
5. limitations
Recommendationsprovidedinthisreportaresubjecttothefollowingconditions:
1) Theexteriorwallsofthestructureshallbecontinuouslysheathedwithaminimum7/16Performance
CategorywoodstructuralpanelsheathingmeetingtherequirementsofDOCPS1orPS2andshallbeattached
toframingwith8dcommonnails(0.131x2-1/2inches)at4inchesoncenteraroundthepanelperimeter
andat12inchesoncenteroverintermediatesupports.
2) TheAPASimplifiedWallBracingMethodshallbeapplicabletobuildingsofnomorethantwostories,subject
totheapplicabilitylistedinSection3.1ofthisreport.
3) Whenplacedovermasonryorconcretestemwalls,wallbracingpanelsusedintheAPASimplifiedWall
BracingMethodshallmeettherequirementsofthe2012IRCSectionR602.10.9.
4) WhiletheAPASimplifiedWallBracingMethodisnotpartofthecode,itisbasedonthecodeandother
modificationspermittedbythe2012IRCSectionsR301.1.3EngineeringDesign.Furthermodifications
totheAPASimplifiedWallBracingMethodbytheuserofthisreportarebeyondthescopeofthisreport.
5) Thisreportissubjecttoperiodicreview.Thelatestcopyofthisreportisavailableforfreedownloadat
www.apawood.org/publications.
appenDix a
Wall Bracing for T- And L-Shaped BuildingsAcommonissuefacedbyresidentialdesignersusingtheAPASimplifiedWallBracingMethodisdeterminingthe
amountandplacementofbracedwallpanelsandwalllinesinnon-rectangularresidentialstructures.Non-rectangular
buildingconfigurationsincludeT-,L-,andU-shapedbuildings.Forsmallerstructures,theAPASimplifiedWallBracing
Methodprovidesaneasysolutionbypermittingtheentirestructuretobecircumscribedbyarectangle.Evenwiththe
circumscribedrectangleproceduredescribedinSection3.2ofthisreport,somehomesfalloutsideofthescopeofthe
APAandIRCsimplifiedbracingprovisionsduetotheirsizeornon-rectangularshape.
Themultiple-rectangleproceduredescribedonpage9simplifiesthedesignprocess,whilestillprovidingasafeand
code-compliantstructure.Anexampleispresentedonpage9foranL-shapedbuilding.Thesameprinciplesapply
toT-andU-shapedbuildings,andothershapesthatcanbedividedintomultiplerectangles.Thismultiple-rectangle
procedureshallbepermittedwhenastructurehasanexteriordimensiongreaterthan60feet,andthus,fallsoutside
ofthescopeoftheAPASimplifiedWallBracingMethod,bydividingthestructureintotwoormoreelementsthatmeet
themaximumdimensionrequirements.
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FigureA1isanexampleofafloorplanthatfallsoutsidetherequirementsoftheAPASimplifiedWallBracingMethod
becauseofthe70-footbuildingdimension.
STEP 1: Divide the structure into rectangular elements. Thereareoftenmultiplewaystodothis.Typically,
theeasiestsolutionistodividethebuildinginsuchawaythatthe“commonside”or“commonwallline”ofthetwo
rectanglescontainswallpanelsthatarepermittedtobeusedforbracing(seeFigureA2).
FIGURE A2 – STEP 1
divide stRuctuRe into RectangulaR elements
40'-0"
Rectangle A
RectangleB Common
wall line
20'-0"
20'-0
"50
'-0"
40'-0"
Rectangle A
RectangleB
20'-0"
20'-0
"50
'-0"
FIGURE A1
FlooR Plan
40'-0"
20'-0"20
'-0"
70'-0
"
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STEP 2: Determine bracing requirements for each individual rectangular element using the APA Simplified Wall Bracing Method. Eachindividualrectangleistreatedandbracedasifitwereacompletelyinde-
pendentandseparatestructurefromtheotherrectangles.Thebracedwalllinelengthsanddistancebetweenbraced
walllinesaremeasuredoneachrectangleseparately(seeFigureA3).Notethatanybracedwalllinewithalengthof
8feetorgreatermusthaveataminimumof3feetofequivalentbracing.
FIGURE A3 – STEP 2
deteRmine bRacing ReQuiRements FoR eacH RectangulaR element sePaRately
Rectangle A
RectangleB
Bracing requirement for Rectangle B
Bracing panel for Rectangle B
Bracing requirement for Rectangle A
Bracing panel for Rectangle A
STEP 3: Rejoin the rectangles with bracing provided, as shown in Figure A4. Therulesthatmustbeapplied
tothecommonsidewhenrejoiningtherectanglesarepresentedbelow.Oncerejoined,theincreasedcommon-side
bracingwillreflecttheappropriatedistributionofload.SeeDetailA.
FIGURE A4 – STEP 3
Rejoin Rectangles WitH bRacing PRovided
Rectangle A
RectangleB
Bracing requirement for Rectangle B
Bracing panel for Rectangle B
Bracing requirement for Rectangle A
Bracing panel for Rectangle A
Rectangle A
RectangleB
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DETAIL A
exPanded vieW oF common side bRacing
Bracing panel for Rectangle B
Bracing panel for Rectangle A
Rectangle A
Interior wall Exterior wallRectangle B
Rules for joining at the common side:1) Thetotalbracingfrombothrectanglesalongthecommonsidemustbeprovidedonthecommonside.
2) IntheexampleshowninFigureA4,thecommonsideofRectangleAhasaportionthatisinterioranda
portionthatisexteriortothehouse,whilethecommonsideofRectangleBisentirelyaninteriorwall.The
bracingpanelsshallbepermittedtoberepositionedorredistributedalongthecommonsideaslongasthe
totalofthepanelsisatleastequaltothetotalofthetwoseparaterectangles.
3) ThewallbracinglocationprovisionsoftheAPASimplifiedWallBracingMethodmustbemetalongthe
commonside,aswellasalongtheextendedwallline.
4) Whenthecommonwalllineforbothrectanglesisaninteriorwall,thecommonwallbracingintheAPA
SimplifiedWallBracingMethodshallbepermittedtobemadeofMethodGB(GypsumBoard)bracing.In
thiscommonwallline,theamountofdoubled-sidedMethodGBbracingalongthecommonwallshallbeat
leasttwotimestherequiredbracinglengthofMethodCS-WSPbracingfoundinTable3ofthisreport.The
MethodGBbracingshallbeattachedtobothsidesoftheframinginaccordancewiththe2012IRCTable
R602.10.4.TheMethodGBpanelsshallbeattachedalongallpaneledgesincludingthetopandbottom
plates.“Floatingthecorners”shallnotbepermitted.
5) Whenthecommonwalllineforbothrectangleshasbothexteriorandinteriorwalllineportions,the
commonwallbracingintheAPASimplifiedWallBracingMethodshallbepermittedtobemadeofboth
MethodCS-WSPandMethodGBbracing.Inthiscase,thetotallengthofthedouble-sidedMethodGBand
thesingle-sidedCS-WSPbracedwallpanelstogethershallnotbelessthantwotimestherequiredlength
ofMethodCS-WSPbracinglistedinTable3ofthisreport(seeNote1below).TheMethodGBbracingshall
beinstalledasrequiredinItem4above.
6) IfinsufficientbracinglengthisavailablealongthecommonwalllineinItem5above,useMethodCS-WSP
intheentirecommonwallline,includingtheinteriorwalllineportion,toavoidtheneedtodoublethe
amountofwallbracingrequiredinTable3ofthisreport.Ifthisstilldoesnotprovidesufficientbracing
length,considerotheroptionsprovidedinSection3.7,Item2,ofthisreport.
Note 1: The 2012 IRC Section R602.10.4.1.5 permits mixing bracing methods in a wall line provided that the longest required
bracing length of the mixed methods is used. As this report only provides the bracing amount for CS-WSP and the double-sided
Method GB is approximately 1/2 of the capacity of Method CS-WSP, doubling the bracing amount listed in Table 3 of this report
provides the required amount of bracing for such cases.
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appenDix B
Example for Computing “Qualified” Wall Bracing Length AnexamplewallconfigurationisshowninFigureB1.Woodstructuralpanelsof7/16PerformanceCategorymeeting
DOCPS2areusedtocontinuouslysheaththewallwith8dcommonnails(0.131x2-1/2inches)at4inchesoncenter
aroundthepanelperimeterandat12inchesoncenteroverintermediatesupports.Thehouseconfigurationmeetsthe
applicabilityrequirementsofthisreport(i.e.,Sections3.1and3.8).
tHe QualiFied Wall bRacing lengtH is deteRmined as FolloWs:
segment length (in.)
greater than length Required
in table 1contributing length (in.)
greater than length Required
in table 2contributing length (in.)
amount of bracing length
contributed (in.)
16 No 0 No 0 0
20 No 0 Yes 11 11
72 Yes 72 – – 72
30 Yes 30 – – 30
12 No 0 No 0 0
32 Yes 32 – – 32
Total = 145 in. or 12.1 ft
FIGURE B1
an examPle Wall conFiguRation
72" 30"
80"60
"
9'-0
"
32"12"16" 20"
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