apa system report, sr-102b - simplified wall bracing ... · pdf fileapa simplified wall...

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

APA Simplified Wall Bracing Method

Form No. SR-102B ■ © 2013 APA – The Engineered Wood Association ■ www.apawood.org

2

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.



3

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



4

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.



5

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



6

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.



7

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.



8

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.

http://www.apawood.org/publications



9

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

"



10

STEP 2: Determine bracing requirements for each individual rectangular element using the APA Simplified Wall Bracing Method. Eachindividualrectangleistreatedandbracedasifitwereacompletelyinde-

pendentandseparatestructurefromtheotherrectangles.Thebracedwalllinelengthsanddistancebetweenbraced

walllinesaremeasuredoneachrectangleseparately(seeFigureA3).Notethatanybracedwalllinewithalengthof

8feetorgreatermusthaveataminimumof3feetofequivalentbracing.


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.


Rejoin Rectangles WitH bRacing PRovided

Rectangle A

RectangleB

Bracing requirement for Rectangle B


Bracing requirement for Rectangle A


Rectangle A

RectangleB



11

DETAIL A

exPanded vieW oF common side bRacing



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.



12

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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Form No. SR-102B/Revised February 2013/0100

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