Prescriptive Deck Details
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This design document applies to sinqle-soan, sinole-level residential decks only. Decks must be constructed in conformance with the details contained herein. A copy of this deck detail must be on the job site and available to the inspector during each required inspection. decking ledger board fasteners ledgerboard attachmentto existinghouse rimjoist joistS post-to-beam connection post ProhibitedLedger Attachments ........................ 11 LedgerBoard Fasteners ..........,.......11 Framingat Chimneyor BayWindow ................. t2 LateralSupport ..............t2 Free-StandingDecks ...... L4 Guards..... ..........t4 GuardPost Attachments....... ...........15 Stair.,...... .............16 SafetyGlazing ...............22 Lumbershall be naturallydurable wood or shallbe southernpine, grade #2 or better that is pressure- preservative-treatedin accordancewith AWPAU1 for the species,product, preservativeand end use. Fieldcut ends,notches and drilledholes of preservativetreated wood shall be treatedin the fleld in accordancewith AWPAM4. Preservative-treated lumber in contactwith the groundshall be ratedas "ground-contact."Please note: not all treated lumber is rated for ground contact. 2. Wood-plasticcomposites are composedof boundwood and plasticfibers creating material that can be usedas deck_ingand guardelements as permittedherein. Permissiblewood-plastic composites must beara labelindicating its performancecriteria and compliancewith ASTMD 7032. 3. Nailsshall be ring-shankedor annulargrooved. 4. Screwsand nailsshall be hot-dippedgalvanized, stainless steel or approvedfor use with pressure treatedlumber. 5. Hardware,e.g., joist hangers,cast-in-place post anchors, mechanical fasteners, shall be galvanized with 1.85oz/sf of zinc(G-185 coating) orshall be stainlesssteel. Useproducts such as"Zmax"from SimpsonStrong-Tie or "TripleZinc" and"Gold Coat" from USP. 6. Electricalreceptacles for decksshall comply with the currentlyapproved edition of the National ElectricalCode. 7. Lightingfor decksand exteriorstairs shall comply with IRC303.7 StairwayIllumination. B. Decksconstructed in accordancewith thesedetails are not approvedfor privary screens'planters, built-inseating or hot tub installations. Placementand attachmentof wood-plastic Approved Material compositesshall be per manufacturer's Woodand wood-plasticcomposite decking shall be instructions. installedin accordancewith the requirementsbelow' . Dimensionsshall be 2x6 or s/+ ("five- (2)ad nails or (2)#A quarter")for woodand per manufacturerfor screws at each joisl wood-plasticcomposites. Wooddecking may be placedat an angleof 45 to 90 degreesto the joists. Attachwood deckingin accordancewith FIGURE1. FIGURE1: WPICAL DECKING . Wood-plasticcomposite label and manufacturer'sinstructions must be left on the jobsitefor inspector verifi cation. Plastic Decking plasticor PVCdecking, not considereda wood-plasticcomposite, may be substitutedonly whenthe producthas a valid evaluationreport from an accreditedlisting agency and is capableof resistinga live loadof 40 PSF. Installationshall be in conformanceto the evaluationrepoft and the manufacturer's installationinstructions which must be availableto the inspector.- loists shallbe designedin accordancewith the requirementsbelow. Joistspan is measuredbetween the centerlineof bearingat eachend of the joist and doesnot includethe overhangs. See FIGURE2 throughFIGURE 4 for joist spantypes. UseTABLE 1 to determineyour joist sizebased on spanlength and spacing. The maximumoverhang is equalto one-fourthof the lengthof the joist span(0.25 x joist span). Attachrim joistto end of joistsas shownin FIGURE2and FIGURE4. attached rim joist to ends of each joist with (3) #10 x 3" wood joist ledgerboard screwsor (3) 10dnails FIGURE 2: JOIST SPAN WITH OVERHANG . DECK ATTACHED AT HOUSE existinghouse wall beam <-joist hanger joist hanger \ \_joist ledger- post board beyond joist span FIGURE 3: JOIST SPAN - JOISTS ATTACHED TO SIDE OF BEAM 2x blocking between joists; attach with (3) 10d toe nails each side + existing house E;-lt--lt--l[--]r-------lr------1f---"lr------l'------r------"lr-----rr--1r------r-------1r------r-----f:-lt-:l attachrimloist+tr,4- wall to endsof each fip- rimjoist joistwith (3) tf---------- #10 x 3" wood screws or (3) 1Odnails FIGURE 4: JOIST SPAN . FREE.STANDING I The maximum length of the overhang is equal to one-fourth of the joist span length (0.25 x joist span). 2 Fo. ro." information on Free-Standing Decks,see Sheet 14. TABLE 1: MAXIMUM JOIST SPAN LENGTH1 Joists without Joist Spacing) L2" 16" 24" Joist Size* 2xB 13'-8" L2',-5" LO'-2" 2x10 L7'-5" 15'-10" 13'-1" 2xL2 1g'-0" 1g'-0u 15'-5" Spans are based on 40 PSF live load, 10 PSFdead load, southern pine #2, normal loading duration, wet service conditions and deflectionsof A=t/360 for main span and V180 for overhang' Beamsshall be designedand assembledin accordancewith the requirementsbelow. As shownin FIGURE5, beamspan is measuredbetween the centerlinesof two adjacentposts. Beamsize is determinedusing TABLE 2. Beamsmay overhangeach end up to one-fourthof the beamspan (0.25 x beamspan) as shownin FIGURE5. Usingthe membersidentified in TABLE2, beamsshall be assembledin accordancewith FIGURE6. Beamsplices shall be locatedover interiorpost locationsonly. joists above =f, F= tvl tvl tAl tAl ri_ W V D{ il( D( -q I t L- -J \-gssrn L beam splices at interior post locations only post,typical optional beam span beamspan optional I overhangl overhang FIGURE 5: BEAM SPAN TYPES I The maximum length of the overhang is equal to one-fourth of the beam span length (0.25 x beam span). TABLE 2: MAXIMUM BEAM SPAN Beam Size) (z)zx6 (2)2x8 (2)2x1o (2)2xr2 (3)2x6 (3)2x8 (3)2x1o (3)2x12 Joist Span9 <6' 7',-t" g'.-2" 11'-10" 13'-11u g',-7" tr'-4" 14',-5u 17'-5" > 6',-I' 6'-2" 7'-LL" 10'-3" 12',-o" 7',-8" 9'-11" Lz',-lO" 15',-1" > B',-10' 5'-6" 7',-L" 9'-2" 10'-9" 6'-11" B'-11u 11'-6u 13'-6" 10' 12' 5'-0" 6'-6" B',-5" 9'-10" 6'-3u g'-1" 10'-6" L2',-4" L2' T4' 4'-8" 6'-0" 7'-9" 9'-1" 5'-10u 7'-6" 9'-9" 11'-5u t4' 16' 4'-4" s',-7" 7'-3" B'-6" 5',-5u 7'-O" 9'-1" 10'-8" 16' 18' 4'-t" 5'-3" 6'-10" B'-0" s'.-2" 6'-7" 8'-7" 10'-1" Spans are based on 40 PSF live load, 10 PSFdead load, southern pine #2, normal loading duration, wet service conditions and deflectionsof A=t/360 for main span and V180 for overhang with a 230 lb. point load. lf a beam is constructedwith 3-plies, attach each -r outside member to the inside as shown herein \ 10dcommon nail or #10 wood screw. 2 common nails or screws at each gtaggeredin 2 rows end and at spliceends Note: spliees are permittedin multi-spanbeams over interiorpost locationsonly. FIGURE 6: BEAM ASSEMBLY DETAIL ffitheexistinghouseon|y,theratiooftheovera||deck|ength,L,totheovera||deck width, W, must be no more than 2 to L as shownin FIGURE7. This requirementcan also be verifiedby ensuringL+w<2. Complete Your Deck A framingplan shows a bird's-eyeview of the joist and beamlayout; the locationof the ledgerboard, diagonalbracing, posts and footings,and the type, sizeand spacingof the ledgerboard fasteners. Use the sampletypical deck framing plan shownin FIGURE7 belowand the requirementsherein to complete your deck. E o o lt 2x_ledger board withbolts, screws, anchon@ _" on center joisthanger (f) ; o joists N 2x_ al12",16"or24" oncenter 2x_rim joist " roundor square footing FIGURE 7: TYPICAL DECK FRAMING PLAN Eachjoist shallbe attachedto the beamas shownin FIGUREB. UseOption 1 or Option2 whenjoists bearon or overhangpast the beamas shownin FIGURE2 and FIGURE4. UseOption 3 whenjoists attach to the sideof the beamas shownin FIGURE3; however,the joist depth must be lessthan or equalin depthto the beamdepth. Seeloist Hangersbelow for informationon hangerrequirements. Mechanical fastenersor hurricaneclips used in Option2 shallhave a minimumcapacity of 100 lbs. in both uplift and lateralload directions. See manufacturer's instructions for minimuminstallation requirements. oPTloN1* OPTION2 OPTION3 (3)8d toe nailed mechanical andjoist (2 onone side, fasteneror topof beam at same '1on the other) hurricaneclip mustbe elevation *Option1 is prohibitedon free-standingdecks FIGURE 8: JOIST-TO.BEAM DETAIL Joisthangers, as shownin FIGURE9, shallhave a minimum joist hangerwith insideflang capacityof 600 lbs.for 2x8s,700 lbs.for 2x10sand 800 lbs. for 2xt2s. Thejoist hangershall be designedand manufacturedfor the numberof pliesit is carrying. Usejoist hangerswith insideflanges when clearancesto the edgeof the beamor ledgerboard dictate. Do not use clip angles or brackets to suppod framing members. Do not bend hanger flanges to accommodate field conditions. FIGURE 9: WPICAL JOIST HANGERS Deckposts shall be 6x6 with a maximumheight of 14'-0" measured from the top of the footingto the undersideof the beam. The beam shallbe attachedto the post by one of the methodsshown in FIGURE 11. The attachmentcondition shown in FIGURE10 is prohibited' The postcap shownin FIGURE11, Option2 shallbe specifically designedfor two- or three-plybeams and 6x6 postswith a minimum downwardallowable load capacity of 5,000 lbs. Attachmentshall be per manufacturer'sinstructions. Post caps shall be galvanizedper the requirementsnoted on Sheet3. 4x4 & 4x6 postscan be usedif tributaryloading values are calculatedby a designprofessional. Cut ends of posts shall be field treated with a wood FIGURE 1O: PROHIBITED preserwative containing copper naphthenate in accordance POST.TO.BEAM ATTACHMENT with AWPA M4. Such products can be found in the paint department of most hardware or home center stores. 3-ply beamsmust use post cap post cap;