Supplement - Structural Use Panels - American Wood Council

SUPPLEMENTStructural-UsePanelsLRFDLOAD AND RESISTANCE FACTOR DESIGNMANUAL FOR ENGINEEREDWOOD CONSTRUCTION

SUPPLEMENTStructural-UsePanelsLRFDLOAD AND RESISTANCE FACTOR DESIGNMANUAL FOR ENGINEEREDWOOD CONSTRUCTIONCopyright © 1996APA – The Engineered Wood Association

PrefaceThis supplement contains adjustment factors, dimensions,factored resistance, reference strengths and otherproperties required to design structural-use panels in theLRFD format. In this format, the term “resistance” isused to refer to member capacities (i.e., moment resistance,compression resistance, etc.). This is distinct fromthe term “strength” which refers to limit state materialproperties — conceptually a “factored allowable stress.”The member resistance values tabulated in thissupplement are to be used in conjunction with thedesign methodologies provided in AF&PA/ASCE 16-95, Standardfor Load and Resistance Factor Design (LRFD)for Engineered Wood Construction.The reference strengths were derived according tothe principles of ASTM D5457-93, Standard Specificationfor Computing the Reference Resistance ofWood-based Materials and Structural Connections forLoad and Resistance Factor Design.The tabulated reference strength values are to be usedwithin the reference end-use conditions defined therein.When the end-use conditions fall outside the range of thereference conditions, the reference values shall be adjustedby the product of applicable adjustment factors as definedin AF&PA/ASCE 16-95 and also provided in this supplement.For unusual end-use conditions, the designer shouldconsult additional literature for possible further adjustments.APA/EWS

TABLE OF CONTENTSChapter/TitlePage4.7 Fire Retardant Treatment Factor, C rt 8.1 GeneralChapter/Title Page1. Designer Flowchart ..................................................1 5. Factored Reference1.1 FlowchartResistance ...................................................................................152. Introduction ................................................................................... 35.1 General5.2 Capacity Selection Tables2.1 Products Description5.3 Factored Reference Shear Resistances2.2 Typical Applicationsfor Shear Walls and Diaphragms2.3 Availability6. Other Considerations .................................. 213. Reference Strength and6.1 Fastening (Nailing) SchedulesStiffness .................................................................................................76.2 Panel Spacing3.1 Derivation of Reference Values6.3 Panel Edge Support3.2 Example Derivation6.4 Panel Specification4. Design Adjustment Factors ....... 11 7. Supplemental Design4.1 GeneralAssistance ...................................................................................254.2 Grade and Construction Factor, C G7.1 General4.3 Width Factor, C w7.2 Load-Span Tables4.4 Moisture Effect Factor, C M7.3 Design Example4.5 Temperature Factor, C t4.6 Preservative Treatment Factor, C pt 8. Section Properties .............................................. 398.2 Section and Weight PropertiesLIST OF TABLES2.1 Typical Panel Constructions ............................................................... 64.1 Moisture Effect Factor, C M ............................................................. 124.2 Grade and Construction Factors, C G ................................... 145.1 Baseline Flexural Capacities .......................................................... 165.2 Baseline Shear Capacities ................................................................ 175.3 Baseline Axial Capacities .................................................................. 175.4 Factored Shear Resistance (kip/ft) forStructural-Use Panel Shear Walls with Framingof Douglas-fir, Larch, or Southern Pine forWind or Seismic Loading .................................................................... 185.5 Factored Shear Resistance (kip/ft) forStructural-Use Panel Horizontal Diaphragmswith Framing of Douglas-fir, Larch, orSouthern Pine for Wind or Seismic Loading .............. 196.1 Minimum Nailing Recommendations for Structural-Use Panel Applications ........................................................................ 226.2 Panel Edge Support ................................................................................... 237.1 Baseline Uniform Load Capacities (psf) ........................ 277.2 OSB Uniform Load Capacities (psf) .................................. 297.3 5-Ply Plywood Uniform Load Capacities (psf) ...... 327.4 4-Ply Plywood Uniform Load Capacities (psf) ...... 347.5 3-Ply Plywood Uniform Load Capacities (psf) ...... 357.6 COM-PLY Uniform Load Capacities (psf) ................ 368.1 Panel Section and Weight Properties .................................. 408.2 Relationship Between Span Rating andNominal Thickness ..................................................................................... 40APA/EWS

APA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT11DESIGNERFLOWCHART1.1 Flowchart 2APA/EWS

2 DESIGNER FLOWCHART1.1 FlowchartStructural-Use PanelSupplementNoEnd-UseConditionsConsistent WithReferenceConditions (a) ?YesSelect Trial Panel (b)NoLoad-SpanCriteria Satisfied ?(Section 7.2)Determine BaselineCapacities (Section 5.2)YesUse Load-Span Tables(Section 7.2)Determine DesignCapacities (c)Factored Strengths >Factored Load Effects ?NoNoFactored Strengths >Factored Load Effects ?YesYesNoDesign Stiffness >Unfactored Load Effects ?Design Stiffness >Unfactored Load Effects ?NoYesAccept Trial PanelYes(a)See Section 4.(b)As a starting point, it is suggested to satisfy stiffness requirements first using load-span tables.(c)Apply end-use and grade-construction factors given in Section 4.APA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT3INTRODUCTION22.1 Products Description 42.2 Typical Applications 52.3 Availability 5Table 2.1 Typical Panel Constructions .................................. 6APA/EWS

4 INTRODUCTION2.1 Products DescriptionStructural-Use PanelsStructural-use panels are wood-based panel products thathave been rated for use in structural applications. Commonapplications for structural-use panels include roofsheathing, wall sheathing, subflooring, and single-layerflooring (combination subfloor-underlayment).Structural-use panels are classified by span ratings.Panel span ratings identify the maximum recommendedsupport spacings for specific end uses. Design capacitiesare provided on the basis of span ratings.Structural-use panel recommendations provided in thissupplement are applicable to panels manufactured in accordancewith the provisions of PS1 and / or PS2.Designer must specify structural-use panels by thespan ratings, nominal thickness, grade and constructionassociated with tabulated design recommendations. Exposuredurability classification must also be identified.Panel GradesBased on PS2 (see Section 6.4), structural-use panelgrade names include Sheathing, Single Floor, and StructuralI Sheathing Corresponding grade names in PS1 areC-D, Underlayment, and Structural I C-D.• Sheathing grade panels are rated for use in subfloor,roof, and wall applications.• Single Floor panels are rated for use as combinationsubfloor-underlayment and are usually manufacturedwith tongue and groove (T&G) edge profiles.• Single Floor panels are typically sanded or touch-sandedwhile Sheathing panels are usually unsanded.• Structural I Sheathing panels meet the requirements ofthe sheathing grade as well as additional requirementsassociated with use in panelized roof systems, diaphragms,and shear walls.Span RatingsSpan ratings indicate the maximum recommendedsupport spacing, in inches, for specific applications. Thespan rating system applies when the panel is applied withthe reference axis across two or more supports. The referenceaxis is usually the primary axis of the panel.• Sheathing: Sheathing panels rated for use in roof orsubfloor applications are identified with a dual spanindex — two numbers separated by a slash. The numberpreceding the slash is the maximum recommendedsupport spacing for roof applications. The number followingthe slash is the maximum recommended supportspacing for subfloor applications. For example, a panelrated as 24/16 may be applied as roof sheathing oversupports spaced 24 inches o.c. or as subfloor over supportsspaced 16 inches o.c. Recommendations for useof sheathing panels also include wall applications.Certain of the roof sheathing spans are dependent uponpanel edge support (see Section 6.3).Sheathing panels rated for use only as wall sheathingare usually identified as either Wall-24 or Wall-16. Thenumerical index (24 or 16) corresponds to the maximumwall stud spacing. Wall sheathing panels areperformance tested with the secondary axis spanningacross supports. For this reason, wall sheathing panelsmay be applied with either the primary or secondaryaxis across supports.• Single Floor: The Single Floor span rating is an indexnumber that provides the maximum recommended supportspacing with the primary axis across two or moresupports. Typical Single Floor span ratings are 20 ocand 24 oc, although 16 oc, 32 oc, and 48 oc Single Floorpanels are also available.Single Floor panels may also carry a dual trademark,for which the second span index covers applicationswith the secondary axis across supports. Such panelsare typically used in flooring systems of manufacturedhousing.Panel Constructions• Plywood: Plywood is comprised of alternating layersof veneer (plies). Each layer consists of one or moreplies. Structural-use plywood panels are assembled withwaterproof adhesive applied between plies. The adhesivecures upon application of heat and pressure.Plywood has been manufactured since the early 1930’sand was the original structural-use panel. Plywood panelswere originally manufactured from Douglas-fir logs.Presently a variety of domestic species are used in plywoodmanufacture. Due to continued strong demandfor forest products, along with artificial constraints onwood supply, imported species are becoming a factorin domestic plywood production.APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER 5• Oriented Strand Board: Oriented strand board (OSB)is comprised of thin rectangular wood strands arrangedin a minimum of three cross-aligned layers and bondedunder heat and pressure with a waterproof and boilproofadhesive. OSB’s predecessor product waswaferboard, a wood panel product that was first commerciallyproduced in the mid-1960’s. Waferboardmanufacture involved a mat-formed panel product withrandom distribution of rectangular wafers. Orientedstrand board, a significantly improved structural panelcompared to waferboard, was first produced in the early1980’s.Oriented strand board is manufactured from hardwoodspecies, softwood species, and mixed species. The hardwoodspecies used are selectively harvested from foreststhat naturally regenerate. The softwood resource is derivedfrom fast-maturing species from managed forests.Much of the softwood resource represents selectiveharvesting from these managed forests.• COM-PLY ®: COM-PLY panels are composite panelsof wood veneer and other wood-based material. COM-PLYpanels are typically manufactured with five layers. Theouter layers and the center layer are wood veneer, andthe two remaining core layers are comprised of woodfiber sandwiched between the veneer layers. COM-PLYpanels are manufactured with waterproof adhesives.COM-PLY was developed as a cooperative effort ofthe U.S. Forest Service and APA to more efficientlyutilize the wood resource.Exposure DurabilityThe following exposure durability classifications arebased on product composition and adhesive bond durability.• Exterior: Exterior panels may be used in applicationsthat are permanently exposed to the weather or to moisture.• Exposure 1: Exposure 1 panels may be used in applicationsthat are not permanently exposed to weather ormoisture, but where resistance to moisture effects dueto high humidity, water leakage, exposure during constructiondelays, or similar exposure conditions, isrequired.• Exposure 2: Exposure 2 panels may be used for interiorapplications requiring resistance to effects of highhumidity and water leakage.2INTRODUCTION2.2 Typical ApplicationsPanel ApplicationsIn addition to roof, subfloor, wall, and single-layerfloor applications, structural-use panels are used in otherapplications. Such applications include structural-insulatedpanels, I-joist webs, materials handling systems (pallets,bins, crating), transportation equipment, and concreteforming.Shear Walls and DiaphragmsStructural-use panels are used as components of wall,floor, and roof systems to resist and transfer in-plane forcesas may be imposed by wind or seismic loading. Shear wallsand diaphragms represent an important application forstructural-use panels.2.3 AvailabilityAlthough other panel constructions may be available,Table 2.1 shows constructions most typically manufactured.Check with suppliers concerning availability.APA/EWS

6 INTRODUCTIONTable 2.1 Typical Panel Constructions (a)PlywoodSpan Rating 3-ply 4-ply 5-ply (b) COM-PLY OSBSHEATHING24/0 ✔ ✔24/16 ✔32/16 ✔ ✔ ✔ ✔40/20 ✔ ✔ ✔ ✔48/24 ✔ ✔ ✔SINGLE FLOOR16 oc ✔20 oc ✔ ✔ ✔ ✔24 oc ✔ ✔ ✔ ✔32 oc ✔ ✔ ✔48 oc ✔ ✔ ✔(a)Constructions listed may not be available in every area. Check with suppliers concerning availability.(b)Applies to plywood with 5 or more layers.APA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT7REFERENCESTRENGTH ANDSTIFFNESS33.1 Derivation of Reference Values 83.2 Example Derivation 8APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER 9 Design Planar Shear Strength, F s NDesign Modulus of Elasticity, ENF sN = (F s) (C G) (C)= (0.161) (1.6) (1.0)= 0.258 ksiEN = (E) (C G) (C)= (1117) (1.1) (1.0)= 1229 ksi3REFERENCE STRENGTH AND STIFFNESSAPA/EWS

10REFERENCE STRENGTH AND STIFFNESSAPA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT11DESIGNADJUSTMENTFACTORS44.1 General 124.2 Grade and Construction Factor, C G 124.3 Width Factor, C w 124.4 Moisture Effect Factor, C M 124.5 Temperature Factor, C t 134.6 Preservative Treatment Factor, C pt 134.7 Fire Retardant Treatment Factor, C rt 13Table 4.1 Moisture Effect Factor, C M .................................. 12Table 4.2 Grade and Construction Factors, C G ................... 14APA/EWS

12 DESIGN ADJUSTMENT FACTORS4.1 GeneralPanel design capacities are determined by multiplyingbaseline capacities, as given in Tables 5.1, 5.2, and5.3, by the grade-construction factor, C G , appropriate foreach specific product. Baseline capacities represent theminimum of each capacity (moment, shear, stiffness,...)for each grade and span rating. Grade-construction factorsare provided in Section 4.2.Tabulated capacities provided in this document aresuitable for reference end-use conditions (see Section 2.5of AF&PA/ASCE 16-95). Reference end-use conditionsare consistent with conditions typically associated withlight-frame construction. For structural-use panels, thesetypical conditions involve the use of full-size untreatedpanels in moderate temperature and moisture exposures.Appropriate adjustment factors are provided for applicationsin which the conditions of use are inconsistentwith reference conditions. In addition to temperature andmoisture, this includes consideration of panel treatmentand size effects. Reference conditions and adjustmentfactors are provided in Sections 4.3 through 4.7.The tabulated adjustment factors are based on datafrom tests of panels bearing the APA trademark.4.2 Grade and Construction Factor, C GReference capacities presented in Tables 5.1, 5.2, and5.3 of this document represent minimum values for eachlisted grade and construction. Table 4.2 provides adjustmentsto the minimum capacities as appropriate for specificconstructions and grades.Note that the capacities given in Tables 5.4 and 5.5 ofthis document for shear walls and diaphragms have takenthe effect of grade and construction into account. Thus,the grade and construction factor shall be taken as unity(C G = 1.0).4.3 Width Factor, C wReference capacities given in Tables 5.1, and 5.3 ofthis document for bending and tension are applicable forpanels 24 inches or greater in width. For panel widths, b,greater than or equal to 8 inches and less than 24 inches,the following width effect factor, C w , shall be applied toreference capacities for bending and tension:For 8 in. ≤ b < 24 in., C w= (8 + b) / 32Note that this factor is not applicable to the capacitiesgiven in Tables 5.4 and 5.5 of this document for shearwalls and diaphragms. Narrow-width shear walls requirespecial design considerations which are beyond the scopeof this document.4.4 Moisture Effect Factor, C MWhen the equilibrium moisture content of structuralusepanels is expected to be 16% or greater in service, themoisture effect factor, C M , shall be applied to referencecapacities given in Tables 5.1 through 5.5 of this document.Table 4.1 Moisture Effect Factor, C MReference CapacityC MStrength 0.75Stiffness 0.85APA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT134.5 Temperature Factor, C tThe temperature effect factor, C t, shall be applied whenstructural-use panels are exposed to in-service sustainedtemperatures. In the range of 100 to 200ºF, the temperatureeffect factor is applicable only when moisture contentof structural-use panels at the elevated temperature canbe expected to remain at 16% or greater for wet-use (moisturecontent 16% or greater) conditions, or at 12% or abovefor dry-use conditions (moisture content below 16%). Thetemperature effect factor shall be computed according tothe following equation:where:C t= 1.0 - α t(T - 100)α t= Temperature effect coefficient = 0.005 forstructural-use panelsT = Temperature (°F)This factor is applicable to the capacities given inTables 5.1 through 5.5 of this document.44.6 Preservative Treatment Factor, C pt4.7 Fire Retardant Treatment Factor, C rtThe information provided in this document does notapply to fire-retardant-treated panels. All capacities andend-use conditions for fire-retardant-treated panels shallbe in accordance with the recommendations of the companyproviding the treating and redrying service.Capacities given in Tables 5.1 through 5.5 apply withoutadjustment (C pt = 1.0) to plywood pressureimpregnated with preservative chemicals and redried inaccordance with American Wood Preservers Association(AWPA) Specification C-9 or Specification C-22. However,due to the absence of applicable treating industrystandards, OSB and COM-PLY panels are not currentlyrecommended for applications requiring pressure-preservativetreating.DESIGN ADJUSTMENT FACTORSAPA/EWS

14 DESIGN ADJUSTMENT FACTORSTable 4.2 Grade and Construction Factors (a) , C GStrength Axis Grade M EI V s V v G v t T P EA3-Ply PlywoodPrimary Structural I 1.0 1.1 1.4 1.3 1.3 1.0 1.0 1.0Other (b) 1.0 1.1 1.0 1.0 1.0 1.0 1.0 1.0Secondary Structural I 1.3 1.5 5.2 1.3 1.3 1.0 1.0 1.0Other (b) 1.0 1.0 2.8 1.0 1.0 1.0 1.0 1.04-Ply Plywood (c)Primary Structural I 1.1 1.1 1.4 1.7 1.7 1.0 1.5 1.0Other (b) 1.1 1.1 1.0 1.3 1.3 1.0 1.5 1.0Secondary Structural I 1.7 3.3 7.9 1.7 1.7 1.0 1.5 1.0Other (b) 1.2 2.2 3.9 1.3 1.3 1.0 1.5 1.05-Ply Plywood (d)Primary Structural I 1.2 1.1 1.6 2.0 1.7 1.3 1.5 1.0Other (b) 1.2 1.1 1.1 1.5 1.5 1.3 1.5 1.0Secondary Structural I 2.8 5.2 1.4 2.0 1.7 1.3 1.5 1.0Other (b) 1.8 3.1 1.0 1.5 1.5 1.3 1.5 1.0OSBPrimary Structural I 1.2 1.0 1.0 2.9 3.1 1.0 1.0 1.0Other (b) 1.2 1.0 1.0 2.9 3.1 1.0 1.0 1.0Secondary Structural I 2.8 5.2 1.0 2.9 3.1 1.3 1.0 1.0Other (b) 1.8 3.1 1.0 2.9 3.1 1.3 1.0 1.0COM-PLYPrimary Structural I 1.2 1.1 1.0 1.7 1.7 1.0 1.0 1.0Other (b) 1.2 1.1 1.0 1.3 1.3 1.0 1.0 1.0Secondary Structural I 1.7 3.3 1.0 1.7 1.7 1.0 1.0 1.0Other (b) 1.2 2.2 1.0 1.3 1.3 1.0 1.0 1.0(a)M = Moment resistance, EI = Flexural stiffness, V s = Planar (Rolling) shear resistance, V v = Through-thickness shear resistance, G v t = Shear rigidity, T = Tensionresistance, P = Compression resistance, and EA = Axial stiffness.(b)Sheathing and Single Floor.(c)Factors for 4-ply also apply to plywood with 5 plys/3 layers.(d)Factors apply to plywood with 5 or more layers.APA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT15FACTOREDREFERENCERESISTANCE55.1 General 165.2 Capacity Selection Tables 165.3 Factored Reference Shear Resistancesfor Shear Walls and Diaphragms 18Table 5.1 Baseline Flexural Capacities ................................ 16Table 5.2 Baseline Shear Capacities ..................................... 17Table 5.3 Baseline Axial Capacities ..................................... 17Table 5.4 Factored Shear Resistance (kip/ft) forStructural-Use Panel Shear WallswithFraming of Douglas-fir, Larch, or SouthernPine for Wind or Seismic Loading ...................... 18Table 5.5 Factored Shear Resistance (kip/ft) forStructural-Use Panel Horizontal Diaphragmswith Framing of Douglas-fir, Larch, orSouthern Pine for Wind or Seismic Loading ...... 19APA/EWS

16 FACTORED REFERENCE RESISTANCE5.1 GeneralThe capacities provided in Tables 5.1 through 5.5 arebased on data from tests of panels bearing the APA trademark.Factored baseline capacities are provided in Table 5.1through Table 5.3. Factored reference shear resistancesfor structural-use panel shear walls (vertical diaphragms)and horizontal diaphragms are given in Tables 5.4 and5.5, respectively, for wind and seismic loading.5.2 Capacity Selection TablesFactored capacities are provided in Table 5.1 throughTable 5.3. The tabulated capacities represent baselinecapacities. The minimum of each specific capacity (moment,shear, stiffness,...) from the various grades and spanratings was used to establish the capacity baseline. Allstructural-use panels referenced in this Supplement meetor exceed the baseline. For design, factored baseline capacitiesshall be adjusted by appropriate grade-constructionfactors and end-use adjustment factors (see Section 4 ofthis Supplement) to provide factored design capacities.Table 5.1 Baseline Flexural Capacities (a,b)Span RatingFactored Moment Resistanceλφ b M (kip-in./ft)Unfactored Flexural StiffnessEI (kip-in. 2 /ft)Axis Primary Secondary Primary SecondarySHEATHING24/0 0.432 0.093 60.00 3.60024/16 0.553 0.111 78.00 5.20032/16 0.639 0.159 115.0 8.10040/20 1.080 0.259 225.0 18.0048/24 1.460 0.389 400.0 29.50SINGLE FLOOR16 oc 0.717 0.173 150.0 11.0020 oc 0.829 0.242 210.0 13.0024 oc 1.106 0.372 300.0 26.0032 oc 1.503 0.657 650.0 75.0048 oc 2.765 1.175 1150 160.0(a)λ = 0.80 and φ b = 0.85. For λ other than 0.80, the tabulated value should be divided by 0.80 and then multiplied by the appropriate λ.(b)For design purposes, the tabulated value shall be multiplied by a grade-construction factor (C G ) given in Section 4.2 and other applicable adjustment factors givenin Section 4.APA/EWS

18 FACTORED REFERENCE RESISTANCE5.3 Factored Reference Shear Resistances for ShearWalls and DiaphragmsTables 5.4 and 5.5 give factored reference shear resistancesfor structural-use panel shear walls (verticaldiaphragms) and horizontal diaphragms for wind and seismicloading. These resistances were developed throughformat conversion from Allowable Stress Design (ASD)to Load and Resistance Factor Design (LRFD).A factor of 1.3 was used to convert the allowable shearforces for shear walls and diaphragms to the LRFD factoredreference shear resistances. This factor is the sameas the load factor specified for wind design cases inAF&PA/ASCE 16-95. Note that the ASD shear capacitiesfor shear walls and diaphragms were based on shorttermloading (i.e., no adjustments for load duration arenecessary when using the ASD tables for shear walls anddiaphragms), which is consistent with the referenced timeeffect in the LRFD.Given the fact that panel shear walls and diaphragmshave performed well under seismic loading in the pastwhen designed in accordance with ASCE 7-88, and thedifference in the load effect for seismic loading betweenASCE 7-88 and ASCE 7-93 is limited, Tables 5.4 and 5.5are considered applicable to seismic loading as well.Table 5.4Factored (a) Shear Resistance (kip/ft) for Structural-Use Panel ShearWalls with Framing of Douglas-fir, Larch, or Southern Pine (b) for Windor Seismic Loading (c)Minimum Minimum Nail Panels Applied Direct to Framing Panels Applied Over 1/2" or 5/8" Gypsum SheathingNominal PanelThicknessPenetration inFramingNail Size(Common or Nail spacing at panel edges (in.)Nail Size(Common or Nail spacing at panel edges (in.)Panel Grade (in.) (in.) Galv. Box) 6 4 3 2 (e) Galv. Box) 6 4 3 2 (e)STRUCTURAL I 5/16 1-1/4 6d 0.26 0.39 0.51 0.66 8d 0.26 0.39 0.51 0.66SHEATHING 3/8 0.30 (d) 0.47 (d) 0.60 (d) 0.79 (d) 0.36 0.56 0.72 0.957/16 1-1/2 8d 0.33 (d) 0.51 (d) 0.66 (d) 0.87 (d) 10d 0.36 0.56 0.72 0.9515/32 0.36 0.56 0.72 0.95 0.36 0.56 0.72 0.9515/32 1-5/8 10d (f) 0.44 0.66 0.86 1.13 -- -- -- -- --SHEATHING 5/16 or 1/4 1-1/4 6d 0.23 0.35 0.46 0.59 8d 0.23 0.35 0.46 0.593/8 0.26 0.39 0.51 0.66 0.26 0.39 0.51 0.663/8 0.29 (d) 0.42 (d) 0.53 (d) 0.69 (d) 0.34 0.49 0.64 0.837/16 1-1/2 8d 0.31 (d) 0.46 (d) 0.59 (d) 0.76 (d) 10d (f) 0.34 0.49 0.64 0.8315/32 0.34 0.49 0.64 0.83 0.34 0.49 0.64 0.8315/32 1-5/8 10d (d) 0.40 0.60 0.78 1.00 -- -- -- -- --19/32 0.44 0.66 0.86 1.13 -- -- -- -- --(a)λ = 1.0, φ z = 0.65(b)For framing of other species: (1) Find specific gravity for species of lumberin the AF&PA National Design Specification, (2) for common or galvanizedbox nails, find shear value from table for nail size for STRUCTURAL Ipanels (regardless of actual grade); for galvanized casing nails, take shearvalue directly from table, (3) multiply this value by 0.82 for species withspecific gravity greater than or equal to 0.42 but less than 0.49, or multiplyby 0.65 for species with specific gravity less than 0.42.(c)All panel edges backed with 2-in. nominal or wider framing. Install panelseither horizontally or vertically. Space nails 6 in. o.c. along intermediateframing members for 3/8-in. and 7/16-in. panels installed on studs spaced24 in. o.c. For other conditions and panel thicknesses, space nails 12 in.o.c. on intermediate supports.(d)Shears are permitted to be increased to values shown for 15/32-in. sheathingwith same nailing, provided (1) studs are spaced a maximum of 16 in.o.c. or (2) if panels are applied with long dimension across studs.(e)Framing at adjoining panel edges shall be 3-in. nominal or wider, and nailsshall be staggered where nails are spaced 2 in. o.c.(f)Framing at adjoining panel edges shall be 3-in. nominal or wider, and nailsshall be staggered where 10d nails having penetration into framing of morethan 1-5/8 in. are spaced 3 in. o.c.APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER 1919Table 5.5Factored (a) Shear Resistance (kip/ft) for Structural-Use PanelHorizontal Diaphragms with Framing of Douglas-fir, Larch, orSouthern Pine (b) for Wind or Seismic LoadingBlocked Diaphragms (c)Unblocked DiaphragmsMinimum MinimumMinimumNominalNail Spacing (in.) at Diaphragm Boundaries (allcases), at Continuous Panel Edges Parallel to Load(Cases 3 & 4), and at All Panel Edges (Cases 5 & 6)Nail Spaced 6 in. Maximum at SupportedEdges (c)Nail Nominal Width of 6 4 2-1/2 (d) 2 (d) Case 1 All otherCommonNailPenetrationin FramingPanelThicknessFramingMemberNail spacing (in.) at other panel edges(Cases 1, 2, 3 & 4)(No unblocked edges orcontinuous joints parallelconfigurations(Cases 2, 3, 4,Panel Grade Size (in.) (in.) (in.) 6 6 4 3 to load) 5 & 6)STRUCTURAL I 6d (f) 1-1/4 5/16 2 0.24 0.33 0.49 0.55 0.21 0.16SHEATHING 3 0.27 0.36 0.55 0.62 0.24 0.188d 1-1/2 3/8 2 0.35 0.47 0.69 0.78 0.31 0.233 0.39 0.52 0.78 0.88 0.34 0.2610d (e) 1-5/8 15/32 2 0.42 0.55 0.83 0.95 0.37 0.283 0.47 0.62 0.94 1.07 0.42 0.31SHEATHING 5/16 2 0.22 0.29 0.44 0.49 0.20 0.14AND 6d (f) 1-1/4 3 0.25 0.33 0.49 0.56 0.22 0.16SINGLE FLOOR 3/8 2 0.24 0.33 0.49 0.55 0.21 0.163 0.27 0.36 0.55 0.62 0.24 0.183/8 2 0.31 0.42 0.62 0.71 0.28 0.213 0.35 0.47 0.70 0.79 0.31 0.238d 1-1/2 7/16 2 0.33 0.44 0.66 0.75 0.30 0.223 0.37 0.49 0.74 0.84 0.33 0.2515/32 2 0.35 0.47 0.69 0.78 0.31 0.233 0.39 0.52 0.78 0.88 0.34 0.2615/32 2 0.38 0.50 0.75 0.85 0.33 0.2510d (e) 1-5/8 3 0.42 0.56 0.85 0.96 0.38 0.2819/32 2 0.42 0.55 0.83 0.95 0.37 0.283 0.47 0.62 0.94 1.07 0.42 0.31a)λ = 1.0, φ z = 0.65(b)For framing of other species: (1) Find specific gravity for species of lumberin the AF&PA National Design Specification, (2) for common or galvanizedbox nails, find shear value from table for nail size for STRUCTURAL Ipanels (regardless of actual grade); for galvanized casing nails, take shearvalue directly from table, (3) multiply this value by 0.82 for species withspecific gravity greater than or equal to 0.42 but less than 0.49, or multiplyby 0.65 for species with specific gravity less than 0.42.(c)Space nails maximum 12 in. o.c. along intermediate framing members (6in. o.c. when supports are spaced 48 in. o.c.).(d)Framing at adjoining panel edges shall be 3-in. nominal or wider, and nailsshall be staggered where nails are spaced 2 or 2-1/2 in. o.c.(e)Framing at adjoining panel edges shall be 3-in. nominal or wider, and nailsshall be staggered where 10d nails having penetration into framing of morethan 1-5/8 in. are spaced 3 in. o.c.(f)8d is recommended minimum for roofs due to negative pressures of highwinds.Notes: Design for diaphragm stresses depends on direction of continuous paneljoints with reference to load, not on direction of long dimension of sheet.Continuous framing may be in either direction for blocked diaphragms.5FACTORED REFERENCE RESISTANCEAPA/EWS

20FACTORED REFERENCE RESISTANCEAPA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT21OTHERCONSIDERATIONS6.1 Fastening (Nailing) Schedules 226.2 Panel Spacing 226.3 Panel Edge Support 226.4 Panel Specification 236Table 6.1 Minimum Nailing Recommendations forStructural-Use Panel Applications....................... 22Table 6.2 Panel Edge Support ............................................... 23APA/EWS

22 OTHER CONSIDERATIONS6.1 Fastening (Nailing) SchedulesTable 6.1Minimum Nailing Recommendations for Structural-Use PanelApplicationsNail Spacing (in.)Recommended Panel IntermediateApplication Nail Size & Type Edges SupportsSINGLE FLOOR--Glue-nailed installationRing- or screw-shank16, 20, 24 oc, 3/4-in. thick or less 6d (a) 12 1224 oc, 7/8-in. or 1-in. thick 8d (a) 6 1232, 48 oc, 32-in. span (c-c) 8d (a) 6 1248 oc, 48-in. span (c-c) 8d (b) 6 6SINGLE FLOOR--Nailed-only installationRing- or screw-shank16, 20, 24 oc, 3/4-in. thick or less 6d 6 1224 oc, 7/8-in. or 1-in. thick 8d 6 1232, 48 oc, 32-in. span 8d (b) 6 1248 oc, 48-in. span 8d (b) 6 6SHEATHING--SubflooringCommon smooth, ring- or screw-shank (c)7/16-in. to 1/2-in. thick 6d 6 127/8-in. thick or less 8d 6 12Thicker panels 10d 6 6SHEATHING--Wall sheathingCommon smooth, ring- or screw-shank orgalvanized box (c)1/2-in. thick or less 6d 6 12Over 1/2-in. thick 8d 6 12SHEATHING--Roof sheathingCommon smooth, ring- or screw-shank (c)5/16-in. to 1-in. thick 8d 6 12 (d)Thicker panels8d ring- or screw-shankor 10d common smooth6 12 (d)(a)8d common nails may be substituted if ring- or screw-shank nails are not available.(b)10d ring-shank, screw-shank, or common nails may be substituted if supports are well seasoned.(c)Other code-approved fasteners may be used.(d)For spans 48 in. or greater, space nails 6 in. at all supports.6.2 Panel SpacingWood-based panel products expand and contractslightly as a natural response to changes in panel moisturecontent. To provide for in-plane dimensional changes,panels should be installed with a 1/8-inch spacing at allpanel end and edge joints. A standard 10d box nail maybe used to check panel edge and panel end spacing.6.3 Panel Edge SupportFor certain span ratings, the maximum recommendedroof span for sheathing panels is dependent upon paneledge support. Although edge support may be providedby lumber blocking, panel clips are typically used whenedge support is required. Table 6.2 summarizes the relationshipbetween panel edge support and maximumrecommended spans.APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER 2323Table 6.2Panel Edge SupportSheathingMaximum Recommended Span (in.)Span rating With Edge Support Without Edge Support24/0 24 20 (a)24/16 24 2432/16 32 2840/20 40 3248/24 48 36(a)20 in. for 3/8-in., 24 in. for 15/32-in. and 1/2-in. panels.6.4 Panel SpecificationGeneralAPA - The Engineered Wood Association7011 South 19th StreetTacoma, Washington 98466-5399U.S.A.Phone: (206) 565-6600Fax: (206) 565-7265Structural-use panel recommendations provided in thisdesign supplement are applicable to PS1 and PS2 panels.Design recommendations are based on structural capacitiesassociated with specific panel classifications.Structural-use panels are classified by span ratings.Designers must specify structural-use panels by thespan ratings, nominal thicknesses, grades, and constructionsassociated with tabulated design recommendations.Exposure durability classification must also be identified.Single Floor panels may have tongue-and-groove orsquare edges. If square edge Single Floor panels are specified,the specification shall require lumber blocking betweensupports.Further information regarding specification of structural-usepanels is provided in the following references.References — Structural-UsePanelsA partial listing of references for further informationon structural-use panels and panel applications follows.Additional information is available from organizationsproviding trademarking and quality assurance services.Structural Board Association45 Sheppard Avenue East, Suite 412,Willowdale, Ontario M2N 5W9CANADAPhone: (416) 730-9090Fax: (416) 730-90136OTHER CONSIDERATIONSPublications• U.S. Product Standard PS1 — Construction and IndustrialPlywood• U.S. Product Standard PS2 — Performance Standardfor Wood-Based Structural-Use Panels• Grades & Specifications• Panel Handbook & Grade Glossary• Residential & Commercial Design/Construction Guide• Diaphragms Design/Construction Guide• Fire Rated Systems Design/Construction GuidePublication• OSB in Wood Frame Construction — U.S. Edition• Design Rated OSB Design Manual — Canadian CodesAPA/EWS

24OTHER CONSIDERATIONSAPA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT25SUPPLEMENTALDESIGNASSISTANCE7.1 General 267.2 Load-Span Tables 267.3 Design Example 387Table 7.1 Baseline Uniform Load Capacities (psf) ............ 27Table 7.2 OSB Uniform Load Capacities (psf) ................... 29Table 7.3 5-Ply Plywood Uniform Load Capacities (psf) ... 32Table 7.4 4-Ply Plywood Uniform Load Capacities (psf) ... 34Table 7.5 3-Ply Plywood Uniform Load Capacities (psf) ... 35Table 7.6 COM-PLY Uniform Load Capacities (psf) ......... 36APA/EWS

26 SUPPLEMENTAL DESIGN ASSISTANCE7.1 GeneralThis section provides maximum load-span tables forstructural-use panels under uniform loading. Baselineload-span tables are provided prior to the constructionspecific(OSB, plywood, COM-PLY) load-span tables.The construction-specific load-span tables provide uniformload capacities for panel constructions that aregenerally available.The “baseline” load-span tables will allow designersto quickly identify potential span rating(s) that may satisfydesign requirements. The baseline load-span tableswere determined on the basis of baseline capacities (Section5) which are based on testing of APA trademarkedstructural-use panels.When structural-use panels are applied with the primaryaxis across supports, three spans are assumed ifsupports are spaced 32 inches o.c. or less. Two spans areassumed when support spacing is greater than 32 incheso.c.When structural-use panels are applied with the secondaryaxis across supports, three spans are assumed forsupport spacings of 16 inches o.c. or less. Two spans areassumed if support spacings are greater than 16 incheso.c. and less than or equal to 24 inches o.c.One-span applications are not covered in the load-spantables. Nominal 2-inch supports were assumed for spansless than 48 inches, and nominal 4-inch supports wereassumed for 48-inch spans.7.2 Load-Span TablesLoad-span tables provided in this section are suitablefor use when the design end-use conditions are consistentwith reference end-use conditions (see Section 4.1). Thefollowing load-span tables were generated with an assumeddead load of 10 psf for shear and moment limitstates. Deflection-limited uniform loads apply in general,as loads are not factored in deflection design.Uniform loads limited by strength capacities (moment,shear) satisfy the following expression:λφRN ≥ 1.2D + 1.6LWhere:λ = Time Effect Factorφ = Resistance FactorRN = Design ResistanceD = Dead Load EffectL = Live Load Effect (roof live, floor live, or snow)Design resistances, time effect factor, and resistancefactors were taken from Section 5.2 of this Supplement.The tabulated uniform loads are not rounded.APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER2727Table 7.1Baseline Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SHEATHING24/0 L/360 234 91 50 25 10 14L/240 351 136 75 37 15 10 21L/180 468 181 100 49 20 13 28M 228 129 90 59 34 19 51V s 342 248 204 161 119 91 21924/16 L/360 304 118 65 32 13 20L/240 456 177 98 48 19 12 30 12L/180 608 235 131 64 26 17 41 16M 291 165 115 75 43 23 60 35V s 393 286 234 185 137 105 219 15932/16 L/360 448 174 96 47 19 12 32 12L/240 672 260 144 71 29 18 12 47 18 13L/180 896 347 193 95 38 24 15 63 24 17M 336 190 133 86 49 26 19 85 49 28V s 435 315 259 204 151 116 100 270 196 15540/20 L/360 877 339 188 93 37 24 15 70 27 19L/240 1315 509 283 139 56 36 23 105 41 29 14L/180 1754 679 377 185 75 48 30 140 54 38 19M 565 319 222 143 82 43 31 138 78 45 30V s 548 397 326 257 190 145 126 342 248 196 15548/24 L/360 1559 604 335 164 67 42 27 115 45 31 15L/240 2338 905 502 247 100 64 40 172 67 47 23L/180 3118 1207 670 329 133 85 54 230 89 63 31M 763 430 300 193 109 57 41 205 116 66 43V s 702 509 417 329 243 186 161 393 286 225 1787SUPPLEMENTAL DESIGN ASSISTANCEAPA/EWS

28 SUPPLEMENTAL DESIGN ASSISTANCETable 7.1(Continued) Baseline Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SINGLE FLOOR16 oc L/360 585 226 126 62 25 16 10 43 17 12L/240 877 339 188 93 37 24 15 64 25 18L/180 1169 453 251 123 50 32 20 86 33 23M 376 213 148 96 55 29 21 93 53 31V s 465 338 277 219 162 124 107 301 219 17220 oc L/360 818 317 176 86 35 22 14 51 20 14L/240 1228 475 264 130 52 33 21 76 29 21 10L/180 1637 634 352 173 70 45 28 101 39 28 14M 435 246 171 111 63 34 24 129 73 42 28V s 548 397 326 257 190 145 126 352 256 202 15924 oc L/360 1169 453 251 123 50 32 20 101 39 28 14L/240 1754 679 377 185 75 48 30 152 59 42 20L/180 2338 905 502 247 100 64 40 203 78 55 27M 579 327 228 147 84 44 31 196 111 63 41V s 702 509 417 329 243 186 161 404 293 231 18232 oc L/360 2533 981 544 267 108 69 44 292 113 80 39L/240 3800 1471 816 401 162 103 65 438 170 120 59L/180 5067 1961 1088 535 216 138 87 585 226 160 79M 786 443 308 198 113 59 42 345 195 109 71V s 825 598 491 387 286 218 189 579 420 331 26148 oc L/360 4482 1735 963 473 191 122 77 624 241 171 84L/240 6723 2603 1444 709 287 183 116 935 362 256 126L/180 8964 3470 1925 946 383 244 154 1247 483 341 168M 1443 813 565 363 205 106 75 615 347 194 125V s 1237 896 735 579 427 326 282 928 673 530 417(a)Values represent unfactored total load (= D + L) and are applicable when λ = 0.8 and dead load (D) = 10 psf.(b)Applicable when nominal 2-in. framing members are used for supports less than 48 in. o.c., and nominal 4-in. framing members are used for supports at 48 in. o.c.(c)Tabulated values are based on the following loading configurations:Primary Axis Across SupportsSecondary Axis Across SupportsSupport Spacing (s) No. of Spans Support Spacing (s) No. of Spanss ≤ 32 in. o.c. 3 s ≤ 16 in. o.c. 3s > 32 in. o.c. 2 24 in. ≥ s > 16 in. 2APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER 2929Table 7.2OSB Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SHEATHING24/0 L/360 234 91 50 25 10 43 17 12L/240 351 136 75 37 15 10 65 25 18L/180 468 181 100 49 20 13 87 34 24M 273 154 108 70 40 22 90 52 30V s 342 248 204 161 119 91 219 159 12624/16 L/360 304 118 65 32 13 63 24 17L/240 456 177 98 48 19 12 94 36 26 13L/180 608 235 131 64 26 17 126 49 34 17M 348 197 138 89 51 27 106 61 35 23V s 393 286 234 185 137 105 219 159 126 9932/16 L/360 448 174 96 47 19 12 98 38 27 13L/240 672 260 144 71 29 18 12 147 57 40 20L/180 896 347 193 95 38 24 15 196 76 54 26M 402 227 159 102 59 31 22 152 86 49 32V s 435 315 259 204 151 116 100 270 196 155 12240/20 L/360 877 339 188 93 37 24 15 217 84 59 29L/240 1315 509 283 139 56 36 23 326 126 89 44L/180 1754 679 377 185 75 48 30 435 168 119 58M 678 382 266 171 97 51 36 246 139 78 51V s 548 397 326 257 190 145 126 342 248 196 15548/24 L/360 1559 604 335 164 67 42 27 356 138 98 48L/240 2338 905 502 247 100 64 40 535 207 146 72L/180 3118 1207 670 329 133 85 54 713 276 195 96M 915 516 359 231 131 68 48 367 208 116 75V s 702 509 417 329 243 186 161 393 286 225 1787SUPPLEMENTAL DESIGN ASSISTANCEAPA/EWS

30 SUPPLEMENTAL DESIGN ASSISTANCETable 7.2(Continued) OSB Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24STRUCTURAL I SHEATHING24/0 L/360 234 91 50 25 10 73 28 20 10L/240 351 136 75 37 15 10 109 42 30 15L/180 468 181 100 49 20 13 146 56 40 20M 273 154 108 70 40 22 139 79 45 30V s 342 248 204 161 119 91 219 159 126 9924/16 L/360 304 118 65 32 13 105 41 29 14L/240 456 177 98 48 19 12 158 61 43 21L/180 608 235 131 64 26 17 211 82 58 28M 348 197 138 89 51 27 164 93 53 35V s 393 286 234 185 137 105 219 159 126 9932/16 L/360 448 174 96 47 19 12 164 64 45 22L/240 672 260 144 71 29 18 12 246 95 67 33L/180 896 347 193 95 38 24 15 328 127 90 44M 402 227 159 102 59 31 22 234 133 75 49V s 435 315 259 204 151 116 100 270 196 155 12240/20 L/360 877 339 188 93 37 24 15 365 141 100 49L/240 1315 509 283 139 56 36 23 547 212 150 74L/180 1754 679 377 185 75 48 30 730 282 200 98M 678 382 266 171 97 51 36 381 215 121 78V s 548 397 326 257 190 145 126 342 248 196 15548/24 L/360 1559 604 335 164 67 42 27 598 231 164 80L/240 2338 905 502 247 100 64 40 897 347 245 121L/180 3118 1207 670 329 133 85 54 1196 463 327 161M 915 516 359 231 131 68 48 570 321 180 116V s 702 509 417 329 243 186 161 393 286 225 178APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER3131Table 7.2(Continued) OSB Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SINGLE FLOOR16 oc L/360 585 226 126 62 25 16 10 133 51 36 18L/240 877 339 188 93 37 24 15 199 77 55 27L/180 1169 453 251 123 50 32 20 266 103 73 36M 451 255 178 115 66 35 25 165 94 53 35V s 465 338 277 219 162 124 107 301 219 172 13620 oc L/360 818 317 176 86 35 22 14 157 61 43 21L/240 1228 475 264 130 52 33 21 236 91 64 32L/180 1637 634 352 173 70 45 28 314 122 86 42M 521 294 205 132 75 40 28 229 130 73 48V s 548 397 326 257 190 145 126 352 256 202 15924 oc L/360 1169 453 251 123 50 32 20 314 122 86 42L/240 1754 679 377 185 75 48 30 471 182 129 63L/180 2338 905 502 247 100 64 40 628 243 172 84M 694 391 273 175 100 52 37 351 198 111 72V s 702 509 417 329 243 186 161 404 293 231 18232 oc L/360 2533 981 544 267 108 69 44 906 351 248 122L/240 3800 1471 816 401 162 103 65 1359 526 372 183L/180 5067 1961 1088 535 216 138 87 1812 702 496 244M 942 531 370 237 135 70 49 618 349 195 126V s 825 598 491 387 286 218 189 579 420 331 26148 oc L/360 4482 1735 963 473 191 122 77 1933 748 529 260L/240 6723 2603 1444 709 287 183 116 2900 1123 793 390L/180 8964 3470 1925 946 383 244 154 3866 1497 1058 520M 1731 975 678 435 246 127 89 1104 622 347 223V s 1237 896 735 579 427 326 282 928 673 530 417(a)Values represent unfactored total load (= D + L) and are applicable when λ = 0.8 and dead load (D) = 10 psf.(b)Applicable when nominal 2-in. framing members are used for supports less than 48 in. o.c., and nominal 4-in. framing members are used for supports at 48 in. o.c.(c)Tabulated values are based on the following loading configurations:Primary Axis Across SupportsSecondary Axis Across SupportsSupport Spacing (s) No. of Spans Support Spacing (s) No. of Spanss ≤ 32 in. o.c. 3 s ≤ 16 in. o.c. 3s > 32 in. o.c. 2 24 in. ≥ s > 16 in. 27SUPPLEMENTAL DESIGN ASSISTANCEAPA/EWS

32 SUPPLEMENTAL DESIGN ASSISTANCETable 7.35-Ply Plywood Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SHEATHING32/16 L/360 493 191 106 52 21 13 98 38 27 13L/240 740 286 159 78 32 20 13 147 57 40 20L/180 986 382 212 104 42 27 17 196 76 54 26M 402 227 159 102 59 31 22 152 86 49 32V s 478 347 284 224 166 127 110 270 196 155 12240/20 L/360 965 373 207 102 41 26 17 217 84 59 29L/240 1447 560 311 153 62 39 25 326 126 89 44L/180 1929 747 414 204 82 52 33 435 168 119 58M 678 382 266 171 97 51 36 246 139 78 51V s 602 437 358 282 209 160 138 342 248 196 15548/24 L/360 1715 664 368 181 73 47 30 356 138 98 48L/240 2572 996 553 271 110 70 44 535 207 146 72L/180 3430 1328 737 362 147 93 59 713 276 195 96M 915 516 359 231 131 68 48 367 208 116 75V s 772 560 459 362 267 204 177 393 286 225 178STRUCTURAL I SHEATHING32/16 L/360 493 191 106 52 21 13 164 64 45 22L/240 740 286 159 78 32 20 13 246 95 67 33L/180 986 382 212 104 42 27 17 328 127 90 44M 402 227 159 102 59 31 22 234 133 75 49V s 694 503 413 325 240 183 159 377 274 216 17040/20 L/360 965 373 207 102 41 26 17 365 141 100 49L/240 1447 560 311 153 62 39 25 547 212 150 74L/180 1929 747 414 204 82 52 33 730 282 200 98M 678 382 266 171 97 51 36 381 215 121 78V s 875 634 520 410 303 231 200 478 347 273 21548/24 L/360 1715 664 368 181 73 47 30 598 231 164 80L/240 2572 996 553 271 110 70 44 897 347 245 121L/180 3430 1328 737 362 147 93 59 1196 463 327 161M 915 516 359 231 131 68 48 570 321 180 116V s 1122 813 666 525 388 295 256 550 399 314 248APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER3333Table 7.3(Continued) 5-Ply Plywood Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SINGLE FLOOR20 oc L/360 900 349 193 95 38 24 16 157 61 43 21L/240 1350 523 290 142 58 37 23 236 91 64 32L/180 1801 697 387 190 77 49 31 314 122 86 42M 521 294 205 132 75 40 28 229 130 73 48V s 602 437 358 282 209 160 138 352 256 202 15924 oc L/360 1286 498 276 136 55 35 22 314 122 86 42L/240 1929 747 414 204 82 52 33 471 182 129 63L/180 2572 996 553 271 110 70 44 628 243 172 84M 694 391 273 175 100 52 37 351 198 111 72V s 772 560 459 362 267 204 177 404 293 231 18232 oc L/360 2787 1079 599 294 119 76 48 906 351 248 122L/240 4180 1618 898 441 179 114 72 1359 526 372 183L/180 5573 2158 1197 588 238 152 96 1812 702 496 244M 942 531 370 237 135 70 49 618 349 195 126V s 908 658 539 425 314 239 208 579 420 331 26148 oc L/360 4930 1909 1059 520 211 134 85 1933 748 529 260L/240 7395 2863 1588 780 316 201 127 2900 1123 793 390L/180 9860 3817 2118 1040 421 268 170 3866 1497 1058 520M 1731 975 678 435 246 127 89 1104 622 347 223V s 1360 986 808 636 470 358 310 928 673 530 417(a)Values represent unfactored total load (= D + L) and are applicable when λ = 0.8 and dead load (D) = 10 psf.(b)Applicable when nominal 2-in. framing members are used for supports less than 48 in. o.c., and nominal 4-in. framing members are used for supports at 48 in. o.c.(c)Tabulated values are based on the following loading configurations:Primary Axis Across SupportsSecondary Axis Across SupportsSupport Spacing (s) No. of Spans Support Spacing (s) No. of Spanss ≤ 32 in. o.c. 3 s ≤ 16 in. o.c. 3s > 32 in. o.c. 2 24 in. ≥ s > 16 in. 27SUPPLEMENTAL DESIGN ASSISTANCEAPA/EWS

34 SUPPLEMENTAL DESIGN ASSISTANCETable 7.44-Ply Plywood Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SHEATHING32/16 L/360 493 191 106 52 21 13 69 27 19L/240 740 286 159 78 32 20 13 104 40 29 14L/180 986 382 212 104 42 27 17 139 54 38 19M 369 209 146 94 54 29 21 102 58 34 22V s 435 315 259 204 151 116 100 1045 758 596 47040/20 L/360 965 373 207 102 41 26 17 154 60 42 21L/240 1447 560 311 153 62 39 25 232 90 63 31L/180 1929 747 414 204 82 52 33 309 119 84 41M 621 351 244 157 90 47 33 165 94 53 35V s 548 397 326 257 190 145 126 1326 961 756 59648/24 L/360 1715 664 368 181 73 47 30 253 98 69 34L/240 2572 996 553 271 110 70 44 379 147 104 51L/180 3430 1328 737 362 147 93 59 506 196 138 68M 839 473 329 212 120 63 44 246 139 78 51V s 702 509 417 329 243 186 161 1527 1106 871 685STRUCTURAL I SHEATHING32/16 L/360 493 191 106 52 21 13 104 40 29 14L/240 740 286 159 78 32 20 13 156 60 43 21L/180 986 382 212 104 42 27 17 208 81 57 28M 369 209 146 94 54 29 21 143 82 46 31V s 607 440 361 285 211 161 139 2115 1532 1206 949SINGLE FLOOR20 oc L/360 900 349 193 95 38 24 16 111 43 30 15L/240 1350 523 290 142 58 37 23 167 65 46 22L/180 1801 697 387 190 77 49 31 223 86 61 30M 478 270 188 121 69 37 26 154 88 50 33V s 548 397 326 257 190 145 126 1366 990 779 61424 oc L/360 1286 498 276 136 55 35 22 223 86 61 30L/240 1929 747 414 204 82 52 33 334 129 91 45L/180 2572 996 553 271 110 70 44 446 173 122 60M 636 359 250 161 92 48 34 235 133 75 49V s 702 509 417 329 243 186 161 1567 1135 893 703(a)Values represent unfactored total load (= D + L) and are applicable when λ = 0.8 and dead load (D) = 10 psf.(b)Applicable when nominal 2-in. framing members are used for supports less than 48 in. o.c., and nominal 4-in. framing members are used for supports at 48 in. o.c.(c)Tabulated values are based on the following loading configurations:Primary Axis Across SupportsSecondary Axis Across SupportsSupport Spacing (s) No. of Spans Support Spacing (s) No. of Spanss ≤ 32 in. o.c. 3 s ≤ 16 in. o.c. 3s > 32 in. o.c. 2 24 in. ≥ s > 16 in. 2APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER3535Table 7.53-Ply Plywood Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SHEATHING24/0 L/360 257 100 55 27 11 14L/240 386 149 83 41 16 10 21L/180 514 199 111 54 22 14 28M 228 129 90 59 34 19 51V s 342 248 204 161 119 91 60732/16 L/360 493 191 106 52 21 13 32 12L/240 740 286 159 78 32 20 13 47 18 13L/180 986 382 212 104 42 27 17 63 24 17M 336 190 133 86 49 26 19 85 49 28V s 435 315 259 204 151 116 100 751 545 42940/20 L/360 965 373 207 102 41 26 17 70 27 19L/240 1447 560 311 153 62 39 25 105 41 29 14L/180 1929 747 414 204 82 52 33 140 54 38 19M 565 319 222 143 82 43 31 138 78 45 30V s 548 397 326 257 190 145 126 953 691 544 428(a)Values represent unfactored total load (= D + L) and are applicable when λ = 0.8 and dead load (D) = 10 psf.(b)Applicable when nominal 2-in. framing members are used for supports less than 48 in. o.c., and nominal 4-in. framing members are used for supports at 48 in. o.c.(c)Tabulated values are based on the following loading configurations:7Primary Axis Across SupportsSecondary Axis Across SupportsSupport Spacing (s) No. of Spans Support Spacing (s) No. of Spanss ≤ 32 in. o.c. 3 s ≤ 16 in. o.c. 3s > 32 in. o.c. 2 24 in. ≥ s > 16 in. 2SUPPLEMENTAL DESIGN ASSISTANCEAPA/EWS

36 SUPPLEMENTAL DESIGN ASSISTANCETable 7.6COM-PLY Uniform Load Capacities (a,b,c) (psf)Primary Axis Across SupportsSecondary Axis Across SupportsSpan Limit Span (in., center-to-center) Span (in., center-to-center)Rating State 12 16 19.2 24 32 40 48 12 16 19.2 24SHEATHING32/16 L/360 493 191 106 52 21 13 69 27 19L/240 740 286 159 78 32 20 13 104 40 29 14L/180 986 382 212 104 42 27 17 139 54 38 19M 402 227 159 102 59 31 22 102 58 34 22V s 435 315 259 204 151 116 100 270 196 155 12240/20 L/360 965 373 207 102 41 26 17 154 60 42 21L/240 1447 560 311 153 62 39 25 232 90 63 31L/180 1929 747 414 204 82 52 33 309 119 84 41M 678 382 266 171 97 51 36 165 94 53 35V s 548 397 326 257 190 145 126 342 248 196 15548/24 L/360 1715 664 368 181 73 47 30 253 98 69 34L/240 2572 996 553 271 110 70 44 379 147 104 51L/180 3430 1328 737 362 147 93 59 506 196 138 68M 915 516 359 231 131 68 48 246 139 78 51V s 702 509 417 329 243 186 161 393 286 225 178SINGLE FLOOR20 oc L/360 900 349 193 95 38 24 16 111 43 30 15L/240 1350 523 290 142 58 37 23 167 65 46 22L/180 1801 697 387 190 77 49 31 223 86 61 30M 521 294 205 132 75 40 28 154 88 50 33V s 548 397 326 257 190 145 126 352 256 202 15924 oc L/360 1286 498 276 136 55 35 22 223 86 61 30L/240 1929 747 414 204 82 52 33 334 129 91 45L/180 2572 996 553 271 110 70 44 446 173 122 60M 694 391 273 175 100 52 37 235 133 75 49V s 702 509 417 329 243 186 161 404 293 231 18232 oc L/360 2787 1079 599 294 119 76 48 643 249 176 86L/240 4180 1618 898 441 179 114 72 965 373 264 130L/180 5573 2158 1197 588 238 152 96 1286 498 352 173M 942 531 370 237 135 70 49 413 233 131 85V s 825 598 491 387 286 218 189 579 420 331 26148 oc L/360 4930 1909 1059 520 211 134 85 1372 531 375 184L/240 7395 2863 1588 780 316 201 127 2058 797 563 277L/180 9860 3817 2118 1040 421 268 170 2744 1062 751 369M 1731 975 678 435 246 127 89 737 416 232 149V s 1237 896 735 579 427 326 282 928 673 530 417(a)Values represent unfactored total load (= D + L) and are applicable when λ = 0.8 and dead load (D) = 10 psf.(b)Applicable when nominal 2-in. framing members are used for supports less than 48 in. o.c., and nominal 4-in. framing members are used for supports at 48 in. o.c.(c)Tabulated values are based on the following loading configurations:Primary Axis Across SupportsSecondary Axis Across SupportsSupport Spacing (s) No. of Spans Support Spacing (s) No. of Spanss ≤ 32 in. o.c. 3 s ≤ 16 in. o.c. 3s > 32 in. o.c. 2 24 in. ≥ s > 16 in. 2APA/EWS

GUIDELINELRFD STRUCTURAL-USETO LRFD FOR STRUCTURALPANELS SUPPLEMENTCOMPOSITE LUMBER 37377.3 Design ExampleThe following example provides an overview of thegeneral procedure for structural-use panel design underuniform loads. This example helps to clarify the modificationsnecessary to design for applications that are notrepresented in the load-span tables.Example - Roof ApplicationPanel: 1/2-inch nominal OSB Sheathing with a 32/16span rating.Application: Roof - primary axis spanning across supportsspaced 24 inches o.c.Solving for W L in our example:W LW T= [767 (120/24 2 ) - 1.2 (10)] / 1.6 = 92.4 psf= W D+ W L= 102 psfThe calculated uniform load controlled by panel designmoment capacity is 102 psf (see Table 7.2).Load Capacity - Planar (Rolling)ShearCalculate uniform load capacity and check resultsusing load-span tables. Assume a 10 psf dead load andthat design end-use conditions are consistent with referenceend-use conditions.Load Capacity - MomentFrom Table 5.1, the baseline factored moment capacityfor Sheathing 32/16 is 0.639 kip-in./ft. From Table4.2, the grade-construction factor for OSB moment capacityis 1.2 when the primary axis is across supports.The end-use adjustment factor is 1.0. Design momentcapacity for this application is:Whereλφ bMN = (0.639) (1.2) (1.0)= 0.767 kip-in./ftThe design equation is:λφ bMN = 1.2 (W DL 2 /K) + 1.6 (W LL 2 /K)L = 24 inches (span between centerline ofsupports)From Table 5.2, the baseline factored planar shearcapacity for Sheathing 32/16 is 0.363 kip/ft. From Table4.2, the grade-construction factor for OSB planar shearcapacity is 1.0. The end-use adjustment factor is also 1.0.The design planar shear capacity for this application is:Whereλφ vV sN = 0.363 (1.0) (1.0)= 0.363 kip/ftThe design equation is:λφ vV sN = 1.2 (W DL /K) + 1.6 (W LL /K)W DW LL = 22.5 inches (clear span)= Dead load = 10 psf= Live loadK = 20 for three or more spans, 19.2 for two spans,and 24 for single span applicationsThis design equation simplifies to:W L= [λφ vV sN (K/L) - 1.2 W D] / 1.67SUPPLEMENTAL DESIGN ASSISTANCEW DW L= Dead load = 10 psf= Live loadSolving for W L in our example:K = 120 for three or more spans, 96 for single andtwo-span applicationsW LW T= [363 (20/22.5) - 1.2 (10)] / 1.6 = 194 psf= W D+ W L= 204 psfThis design equation simplifies to:W L= [λφ bMN (K/L 2 ) - 1.2 W D] / 1.6The calculated uniform load controlled by panel designplanar shear capacity is 204 psf (see Table 7.2).APA/EWS

38 SUPPLEMENTAL DESIGN ASSISTANCELoad Capacity - DeflectionFrom Table 5.1, the baseline stiffness for Sheathing32/16 is 115 kip-in. 2 /ft. From Table 4.2, the grade-constructionfactor for OSB sheathing stiffness is 1.0. Theend-use adjustment factor is also 1.0. The design stiffnessis:Where(EI)N = (115) (1.0) (1.0)= 115 kip-in. 2 /ftThe design equation is:δ = W L 4 / [K 1(EΙ)N]δ = Deflection criterionL = Clear span plus support-width factor that isequal to 0.25 inch for two-inch-nominal lumberframing and 0.625 inch for four-inch-nominallumber framing.For the example application, K 1 = 1743, K 2 (live load)= 240, K 2 (total load) = 180, and L = 24 - 1.5 + 0.25 =22.75 inches.For uniform roof live load:W L= [115000/(22.75 3 )] (1743/240) = 71 psfTotal uniform load for roof applications:W T= [115000/(22.75 3 )] (1743/180) = 95 psfThe total uniform load limited by the L/180 deflectioncriterion is 95 psf. The uniform roof live load limitedby the L/240 deflection criterion is 71 psf (see Table 7.2).Example SummaryPanel: 1/2-inch nominal OSB Sheathing with a32/16 span rating.Application: Roof - primary axis spanning across supportsspaced 24 inches o.c.K 1= 1743 for three spans, 2220 for two spans, and921.6 for single span applicationsThe deflection criterion term may be expressed as:Limit StateMomentPlanar ShearStiffness, L/240Stiffness, L/180Uniform Load Capacity102 psf204 psf71 psf (live)95 psf (total)δ = L/K 2Where K 2 is a constant (180, 240, or 360).Substituting the deflection criterion term into the designequation and rearranging yields:These values check with capacities provided in thetable of OSB uniform load capacities (Table 7.2) for thecorresponding application. The uniform load capacity forthis design is 71 psf, as governed by the live load deflection.W = [(EΙ)N/L 3 ] (K 1/K 2)APA/EWS

LRFD STRUCTURAL-USE PANELS SUPPLEMENT39SECTIONPROPERTIES8.1 General 408.2 Section and Weight Properties 40Table 8.1 Panel Section and Weight Properties................... 40Table 8.2 Relationship Between Span Rating andNominal Thickness ................................................ 40 8APA/EWS

40 SECTION PROPERTIES8.1 GeneralSection and weight properties are provided in Section8.2. Nominal panel thicknesses tabulated in Table8.1 were used to calculate section properties. The tabulatedsection properties were calculated assuminghomogeneous rectangular cross sections of one-foot width.Relationships between nominal thickness and spanrating are provided in Table 8.2. The predominant nominalthickness available for each span rating is designatedby the letter “P”. The predominant nominal thickness isalso the appropriate thickness for establishing section propertiesfor design.Reference strength and stiffness may be calculatedusing applicable section properties from Table 8.1 anddesign capacities given in Table 5.1, Table 5.2, or Table5.3. An example derivation is provided in Section 3.2.8.2 Section and Weight PropertiesTable 8.1Panel Section and Weight Properties (a)Moment of Section Statical ShearNominal Approximate Thickness Area Inertia Modulus Moment ConstantThickness Weight (b) t A I S Q Ib/Q(in.) (psf) (in.) (in. 2 /ft) (in. 4 /ft) (in. 3 /ft) (in. 3 /ft) (in. 2 /ft)3/8 1.1 0.375 4.500 0.053 0.281 0.211 3.007/16 1.3 0.437 5.250 0.084 0.383 0.287 3.5015/32 1.4 0.469 5.625 0.103 0.440 0.330 3.751/2 1.5 0.500 6.000 0.125 0.500 0.375 4.0019/32 1.8 0.594 7.125 0.209 0.705 0.529 4.755/8 1.9 0.625 7.500 0.244 0.781 0.586 5.0023/32 2.2 0.719 8.625 0.371 1.033 0.775 5.753/4 2.3 0.750 9.000 0.422 1.125 0.844 6.007/8 2.6 0.875 10.500 0.670 1.531 1.148 7.001 3.0 1.000 12.000 1.000 2.000 1.500 8.001-1/8 3.3 1.125 13.500 1.424 2.531 1.898 9.00(a)Properties based on rectangular cross section of 1-foot width.(b)Approximate plywood weight for calculating actual dead loads. For OSB and COM-PLY panels, increase tabulated weights by 10%.Table 8.2Relationship Between Span Rating and Nominal ThicknessSpan RatingNominal Thickness (in.)3/8 7/16 15/32 1/2 19/32 5/8 23/32 3/4 7/8 1 1-1/8SHEATHING24/0 P A A A24/16 P A A32/16 P A A A40/20 P A A A48/24 P A ASINGLE FLOOR16 oc P A20 oc P A24 oc P A32 oc P A48 oc PP = Predominant nominal thickness for each span rating.A = Alternative nominal thickness that may be available for each span rating. Check with suppliers regarding availability.APA/EWS

ADDITIONALINORMATIONAbout APA – The EngineeredWood Association and EngineeredWood SystemsAPA – The Engineered Wood Association isa nonprofit trade association whose membermills produce approximately 75 percent ofthe structural wood panel products manufacturedin North America.The Association’s trademark appears onlyon products manufactured by member millsand is the manufacturer’s assurance thatthe product conforms to the standard shown onthe trademark. That standard may be an APAperformance standard, the Voluntary ProductStandard PS 1-95 for Construction and IndustrialPlywood or VoluntaryProduct Standard PS 2-92, PerformanceStandards for Wood-Based Structural-UsePanels. Panel quality of all APAtrademarked products is subject toverification through APA audit.APA’s services go far beyond quality testingand inspection. Research and promotionprograms play important roles in developingand improving plywood and other panelconstruction systems, and in helping usersand specifiers to better understand and applypanel products.Always insist on panels bearing the markof quality – the APA trademark. Your APApanel purchase is not only your highestpossible assurance of product quality, but aninvestment in the many trade services thatAPA provides on your behalf.The APA EWS trademark appears only onengineered wood products manufactured bymembers of Engineered Wood Systems, arelated corporation of APA. The marksignifies that the manufacturer is committedto a rigorous program of quality verificationand testing and that products are manufacturedin conformance with an APA or nationalstandard such as ANSI StandardA190.1, American National Standard forStructural Glued Laminated Timber.For additional information on woodconstruction systems, contact APA – TheEngineered Wood Association, P.O. Box11700, Tacoma, Washington 98411-0700,or the nearest APA regional field officelisted on the back cover. For a list ofadditional APA and Engineered WoodSystems publications, request the:APA Publications Index, Form B300EWS Publications Index, Form S400The product use recommendations in this publicationare based on the continuing programs oflaboratory testing, product research, and fieldexperience of APA – The Engineered WoodAssociation and Engineered Wood Systems.However, because APA and Engineered WoodSystems have no control over quality ofworkmanship or the conditions under whichstructural panels and engineered wood productsare used, those organizations cannot acceptresponsibility for product performance ordesigns as actually constructed. Becauseengineered wood products performance requirementsvary geographically, consult your localarchitect, engineer or design professional toassure compliance with code, construction,and performance requirements.

We have field representatives in most major U.S.cities and in Canada who can help answer questionsinvolving APA trademarked products.For additional assistance in specifying APA panelproducts, get in touch with your nearest APAregional office. Call or write:WESTERN REGION7011 So. 19th St. P PO. Box 11700Tacoma, Washington 98411-0700(206) 565-6600 P Fax: (206) 565-7265EASTERN REGION2130 Barrett Park Drive, Suite 102Kennesaw, Georgia 30144-3681(770) 427-9371 P Fax: (770) 423-1703U.S. HEADQUARTERS ANDINTERNATIONAL MARKETING DIVISION7011 So. 19th St. P PO. Box 11700Tacoma, Washington 98411-0700(206) 565-6600 P Fax: (206) 565-7265Internet address: http://www.apawood.org(Offices: Antwerp, Belgium; London, United Kingdom;Madrid, Spain; Hamburg, Germany; Mexico City, Mexico;Tokyo, Japan.) For Caribbean/Latin America,contact headquarters in Tacoma.12-96 5M