572 Span Tables - Bear Creek Lumber : Washington …

1 WesternWoodProductsAssociationWestern LumberSPAN TABLESfor Floor and Ceiling Joists and Roof RaftersBASE VALUESfor dimension lumbercomputed withCEILING JOISTSCJ-120#LL10#DLL/360 .. 19CJ-220#LL10#DLL/240 .. 19CJ-310#LL10#DLL/360 .. 20CJ-410#LL5#DLL/240 .. 20 ROOF RAFTERSRR-120#LL7#DLL/180 .. 21RR-220#LL7#DLL/240 .. 21RR-320#LL15#DLL/180 .. 22RR-420#LL15#DLL/240 .. 22RR-520#LL15#DLL/360 .. 23RR-620#LL25#DLL/240 .. 23RR-720#LL30#DLL/360 .. 24RR-820#SL10#DLL/240 .. 24RR-925#SL10#DLL/240 .. 25RR-1030#SL10#DLL/240 .. 25RR-1140#SL10#DLL/240 .. 26RR-1260#SL10#DLL/240 .. 26RR-1320#SL7#DLL/180 .. 27RR-1425#SL7#DLL/180 .. 27RR-1530#SL7#DLL/180.

2 28RR-1640#SL7#DLL/180 .. 28RR-1760#SL7#DLL/180 .. 29RR-1880#SL7#DLL/180 .. 29RR-19100#SL7#DLL/180 .. 30RR-2020#SL15#DLL/180 .. 30RR-2125#SL15#DLL/180 .. 31RR-2230#SL15#DLL/180 .. 31RR-2340#SL15#DLL/180 .. 32RR-2460#SL15#DLL/180 .. 32RR-2580#SL15#DLL/180 .. 33RR-26100#SL15#DLL/180 .. 33RR-2720#SL15#DLL/240 .. 34RR-2825#SL15#DLL/240 .. 34RR-2930#SL15#DLL/240 .. 35RR-3040#SL15#DLL/240 .. 35RR-3160#SL15#DLL/240 .. 36RR-3280#SL15#DLL/240 .. 36RR-33100#SL15#DLL/240 .. 372 table OF CONTENTSA bout WWPA .. 3 Species Groupings .. 3 Design Values .. 3 Mechanical Properties .. 4 Design Criteria .. 5 Using Western Lumber span Tables .

3 5 span Measurement .. 5 Bending .. 5 Repetitive Member .. 5 Duration of Load Criteria .. 5 Deflection.. 5 Horizontal Shear and Compression Perpendicular-to-Grain .. 6 Example 1: Analysis for Fc .. 6 Conversion Diagram for Rafters .. 7 Western Lumber span Tables (see below) .. 8-47 FLOOR JOISTSFJ-130#LL10#DLL/360 .. 8FJ-230#LL25#DLL/360 .. 8FJ-340#LL10#DLL/360 .. 9FJ-440#LL20#DLL/360 .. 9FJ-540#LL25#DLL/360 .. 10FJ-650#LL10#DLL/360 .. 10FJ-750#LL20#DLL/360 .. 11FJ-850#LL25#DLL/360 .. 11FJ-960#LL10#DLL/360 .. 12FJ-1060#LL20#DLL/360 .. 12FJ-1160#LL25#DLL/360 .. 13FJ-1275#LL10#DLL/360 .. 13FJ-1375#LL20#DLL/360.

4 14FJ-1475#LL25#DLL/360 .. 14FJ-1580#LL10#DLL/360 .. 15FJ-1680#LL20#DLL/360 .. 15FJ-1780#LL25#DLL/360 .. 16FJ-18100#LL10#DLL/360 .. 16FJ-19100#LL20#DLL/360 .. 17FJ-20100#LL25#DLL/360 .. 17FJ-21125#LL10#DLL/360 .. 18FJ-22125#LL20#DLL/360 .. 18 WWPA 1992, 20013RR-3420#SL25#DLL/240 .. 37RR-3525#SL25#DLL/240 .. 38RR-3630#SL25#DLL/240 .. 38RR-3740#SL25#DLL/240 .. 39RR-3860#SL25#DLL/240 .. 39RR-3980#SL25#DLL/240 .. 40RR-40100#SL25#DLL/240 .. 40RR-4120#SL15#DLL/360 .. 41RR-4225#SL15#DLL/360 .. 41RR-4330#SL15#DLL/360 .. 42RR-4440#SL15#DLL/360 .. 42RR-4560#SL15#DLL/360 .. 43RR-4680#SL15#DLL/360 .. 43RR-47100#SL15#DLL/360 .. 44RR-4820#SL30#DLL/360.

5 44RR-4925#SL30#DLL/360 .. 45RR-5030#SL30#DLL/360 .. 45RR-5140#SL30#DLL/360 .. 46RR-5260#SL30#DLL/360 .. 46RR-5380#SL30#DLL/360 .. 47RR-54100#SL30#DLL/360 .. 47 ABOUT WWPAW estern Wood Products Association (WWPA) provides lumbergrading, technical support and business information services forthe Western Lumber products of its Member companies. Approvedby the Board of Review of the American Lumber StandardCommittee, Inc. (ALSC), which operates under the jurisdiction ofthe Department of Commerce, WWPA is certified as a lumberinspection and rules-writing buyers can look to WWPA s registered grade mark forthe assurance Lumber will consistently meet grade specificationsand performance standards.

6 The Association monitors lumbergrading and product quality control at its Member mills and pro-vides mill inspection, Lumber grader training and incentive pro-grams, MSR and glued products standards, resource recoveryand mill efficiency addition, WWPA provides technical support services andinformation on Western Lumber end uses to Lumber buyersthroughout the world, and publishes a variety of statistical reportson Western Lumber production, distribution and Member companies of WWPA support the many programsthat assist buyers in specifying and using Western Lumber prod-ucts. These companies are among the leaders in the lumberindustry in supplying quality products to users information about WWPA is available online Web site visitors can view technical informationon Western Lumber , order publications and access a searchable,interactive Buyer s GROUPINGS Marketing CategoriesWestern Lumber is often harvested, manufactured and sold inspecies groupings known as marketing categories.

7 Some of themore than 20 commercially important softwood species are inter-changeable in that they share performance properties and aresimilar in appearance. For structural applications, Western speciesreadily combine into six Species Groups, shown Standard Species Combinations for structurally gradedWestern Lumber are also shown on this Combinations are available in non-structural species are also available separately, in both structural andnon-structural grades. However, when a species combinationother than one of those shown on this page is used for structuralapplications, the species within the combination with the lowestassigned design value will govern.

8 Refer to WWPA s WesternLumber Product Use Manualor the Western Lumber GradingRulesfor additional VALUESD esign values for North American softwood structural lumberare computed in accordance with ASTM standards based onclear-wood tests or on tests of full-size pieces in specific applicable standards, based on results of tests conducted incooperation with the USDA Forest Products Laboratory, are ASTMS tandards D 2555and D 245for clear wood, and D 1990for full-size specimens (the In-Grade Testing Program). Refer to to of the Western Lumber Grading Rulesforadditional Douglas Fir-LarchDouglas Fir-SouthHem-FirSpruce-Pine-Fir(South)We stern CedarsDouglas Fir Pseudotsuga menziesiiWestern Larch Lar ix occidentalisDouglas Fir-South Pseudotsuga menziesii(Grown in AZ, CO, NV,NMand UT)Western Hemlock Tsuga heterophyllaNoble Fir Abies proceraCalifornia Red Fir Abies magnifica Gran d Fir Abies g randisPacifi c Silver Fir Abies amabilisWhite Fir Abies concolorSitka Spruce Picea sitchensisEngelmann Spruce Picea engelmanniiLodgepole Pine Pin us contortaAlpine Fir Abies lasiocarpa(or Subalpine Fir)

9 Ponderosa Pine Pinus ponderosaSugar Pine Pinus lambertianaIdaho White Pine Pinus monticola(or W estern White Pine)Mountain Hemlock Tsuga mertensianaIncense Cedar Libocedrus decurrensWestern Red Cedar Thuja plicataPort Orford Cedar Chamaecyparis lawsonianaAlaskan Cedar Chamaecyparis nootkatensisWestern WoodsSpeciesGroupsStandard SpeciesCombinationsMECHANICAL PROPERTIES RELATED TO BENDING MEMBERSL umber strength properties are assigned to five basic strengthproperties: fiber stress in bending (Fb), tension parallel-to-grain(Ft), horizontal shear (Fv), compression perpendicular-to-grain(Fc )and compression parallel-to-grain (Fc//). The modulus ofelasticity (E or MOE) is a ratio of the amount a piece of Lumber willdeflect in proportion to an applied load.

10 It is a measurement ofstiffness and not a strength span Tables are calculated based on MOE and addition Fc and Fvare included as a consideration for selec-tion of joist and Fiber Stress in Bending - Fb(Fig. 1)Whenloads are applied, structural members bend, producing tension inthe fibers along the faces farthest from the applied load and com-pression in the fibers along the face nearest to the applied induced stresses in the fibers are designated as extremefiber stress in bending (Fb).Single Member Fbdesign values areused in designwhere the strengthof an individualpiece, such as abeam, may be solelyresponsible forcarrying a specificdesign Member Fbdesign values are used in design whenthree or more load sharing members, such as joists, rafters, orstuds, are spaced no more than 24" apart and are joined by floor-ing, sheathing or other load-distributing elements.