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eCopy, Inc. Page 1 e m A W M C A . MW Design for Prescriptive Residential Wood Gmde I Residential Code Deck Construction Based on the 2009 internationa attachment to existing house existing house floor construction ledger board guard post attachment joist-to~beam post~to-beam connection (flush. tight bearmg) post footing connection Where applicable, provisions and details contained in this document are based on the International Residential Code (IRC) [bracketed text references applicable sections of the /RC]. Prescriptive construction methods recommended meet or exceed minimum requirements of the IRC. Provisions that are not found in the /RC are recommended as good industry practice. Where differences exist between provisions of this document and the /RC, provisions of the /RC shall apply. This document is not intended to preclude the use of other construction methods or materials. All construction and materials must be approved by the authority having jurisdiction. Every effort has been made to reflect the language and intent of the IRC. However, no assurance can be given that designs and construction made in accordance with this document meet the requirements of any particularjurisdiction. Copyright © 2010 American Forest & Paper Association, Inc. Page 2 PRESORIPTIVE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE CONTENTS MINIMUM REQUIREMENTS ........................................ ..2 PROHIBITED LEDGER ATTACHMENTS ................. .. 12 DECKING REQUIREMENTS .................................. .., .... ..3 LEDGER BOARD FASTENERS .................................. .. 12 J OIST SIZE ....................................................................... ..3 FREE-STANDING DECKS ........................................... .. 14 BEAM SIZE & ASSEMBLY REQUIREMENTS ........... ..5 DECK STABILITY ........................................................ .. 14 DECK FRAMING PLAN ................................................. ..6 GUARD REQUIREMENTS .......................................... .. 15 JOIST-TO-BEAM CONNECTION .................................. ..7 GUARD POST ATTACHMENTS ................................ .. 16 JOIST HANGERS ............ .............................................. ..7 STAIR REQUIREMENTS ............................................. .. 17 POST REQUIREMENTS ................................................. ..7 STAIR HANDRAIL REQUIREMENTS ....................... .. 18 RIM IOIST REQUIREMENTS ........................................ ..8 STAIR FOOTIN G REQUIREMENTS .......................... .. 19 F OOTIN GS ...................................................................... ..9 STAIR LIGHTING REQUIREMENTS ......................... .. 19 LEDGER ATTACHMENT REQUIREMENTS ............. .. 10 FRAMING AT CHIMNEY OR BAY WINDOW ......... .. 19 MINIMUM REQUIREMENTS I Fasteners other than nails and timber rivets shall 1. This document applies to single level residential wood decks only. 2. All lumber shall be identified by the grade mark of, or certificate of inspection issued by, an approved lumber grading or inspection bureau or agency (www.alsc.org). All lumber shall be a naturally durable species (such as Redwood or Western Cedars) or be pressure-treated with an approved process and preservative in accordance with American Wood Protection Association standards (such as but not limited to those shown in Table 1) [R317 and R318]. All lumber in contact with the ground shall be approved preservative treated wood suitable for ground contact. [R3 17. 1 .2] 3. All nails shall meet the requirements of AST M F 1667. Threaded nails as stated in this document include helical (spiral) and annular (ring-shank) nails. Wood screws shall meet the requirements of ANSI/ASME B18. 6.] . Bolts and lag screws shall meet the requirements of ANSI/ASME B I 8.2.] . 4. Throughout this document, ‘/2" diameter bolts and lag screws are specified for various connections. Edge distance and spacing requirements are based on 1/2" diameter fasteners. If larger (or smaller) fasteners arespecified, edge distance and spacing needs to be adjusted. 5. To resist corrosion, the following is required [R3173]: I All screws, bolts, and nails for use with preservative treated wood shall be hot-dipped zinc-coated galvanized steel, stainless steel, silicon bronze, or copper. Fasteners to be hot-dipped galvanized shall meet the requirements of ASTM A I 53, Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware, Class D for fasteners 3/8" diameter and smaller or Class C for fasteners with diameters over 3/8". . be permitted to be of mechanically deposited zinc- coated steel with coating weights in accordance with ASTM B 695, Class 55, minimum. All hardware (joist hangers, cast-in-place post anchors, etc.) shall be galvanized or shall be stainless steel. Hardware to be hot-dipped prior to fabrication shall meet AST M A 653, Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process, G-185 coating. Hardware to be hot-dipped galvanized after fabrication shall meet ASTMA123, Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products. I Fasteners and connectors exposed to salt water or located within 300 feet of a salt water shoreline shall be stainless steel grade 304 or 316. Other coated or non-ferrous fasteners or hardware shall be as approved by the authority having jurisdiction. 6. Decks supporting large concentrated loads such as hot tubs are beyond the scope of this document. 7. This document does not apply to decks which will experience snow loads, snow drift loads, or sliding snow loads that exceed 40 psf. This document does not address wind or seismic design issues. 8. Flashing shall be corrosion-resistant metal [R703.8] of minimum nominal 0.019-inch thickness or approved non—metallic material. Aluminum should not be used in direct contact with lumber treated with preservatives that contain copper such as ACQ, Copper Azole, or ACZA. 9. Decks shall not be used or occupied until final inspection and approval is obtained. 10. This document is not intended to preclude the use of other construction methods or materials not shown herein. American Wood Council Page 3 ' ‘ EPITESCRIPTIVE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE _ Table 1. Common preservative treatments and retentiori levels (pcf) for sawn lumber in ground contact.a Species ACQ-B ACQ-C ACQ-D CA-B CuN-W Southern Pine 0.40 0.40 0.40 0.21 0.11 Douglas Fir-Larch 0-40 0140 NR 0.21 ' 0.11 |-|em_Fir 0.40 0.40 0.40 0.21 0.11 ponderosa pine 0.40 0.40 0.40 0.21 0.11 Red pine 0.40 0.40 0.40 0.21 0.11 spruCe_Pine-F;r. NR 0.40 NR NR NR Redwood "NR NR NR .NR NR 3 Preservatives and retentions listed in Table 1 are based on the American Wood Protection Association (AWPA) Book of Standards. NR = Treatments Not Recommended. DECKIN G REQUIREMENTS All decking material shall be composed of dimension lumber (2" nominal thickness) or span rated decking in accordance with the American Lumber Standard Committee Policy for Evaluation of Recommended Spans for Span Rated Decking Products (November 5, 2004). Attach decking to each joist with 2-8d threaded nails or 2-#8 screws. Space decking boards approximately '/8" apart. See Figure 11 for decking connection requirements at the rim joist. Decking may be placed from an angle perpendicular to the joists to an angle of 45 degrees to the joists. Each segment of decking must bear on a minimum of 4 joists (or 4 supports). Decking not meeting these requirements may be substituted when the product has been approved by the authority having jurisdiction. J OIST SIZE The span of a joist is measured from the centerline of bearing at one end of the joist to the centerline of hearing at the other end of the joist and does not include the length of the overhangs. Use Table 2 to determine joist span based on lumber size and joist spacing. See Figure l and Figure 2 for joist span types. Table 2. Maximum Joist Spans (LJ) Joist Spacing (o.c.) Without Overhangs1 With Overhangs up to L J/42 Species Size 12" 16" 24" 12" 16" 24" 2X8 13' - 8" 12' — 5" 10' - 2" 10' - 9" 10' - 9" 10' - 2" SOLI‘IhGI'I1 Pine 2X10 17' - 5" 15'-10" 13' - 1" 15' - 6" 15' - 6" 13' - 1" 2X12 18'-0" 18'-0" 15'-5" 18'-0" 18'- 0" 15'-5" Douglas Fir_ 2X8 12' - 6" 11' - 1" 9' - 1" 9' - 5" 9' - 5" 9' - 1" Larch, H8lTl—Fll‘, 2X10 15'-8" 13'-7" 11'-1" 13'-7" 13'-7" 11' - 1" SPF3 2X12 18' - 0'I 15' - 9" 12' - 10" 18' - 0" 15' - 9" 12' -10" Redwood, 2X8 11' - 8" 10' - 7" 8' - 8" 8' ~ 6" 8' — 6" 8' - 6" . |',":f;:;2sc;e§i:r:1, 2x10 14' - 11" 13' - 0" 10' - 7" 12' - 3" 12' - 3" 10' - 7" Red Pine4 2x12 17' - 5" 15' - 1" 12' - 4" 16' - 5" 15' - 1" 12' - 4" 1. Assumes 40 psf live load, 10 psf dead load, L/360 deflection, No.2 grade, and wet service conditions. See Figure 1B. 2. Assumes 40 psf live load, 10 psf dead load, L/180 cantilever deflection with 220 lb point lead, No.2 grade, and wet service conditions. See Figure 1A and Figure 2. 3. lncising assumed for refractory species including Douglas fir-larch, hem-fir, and spruce-pine-fir. 4. Design values based on northern species with no incising assumed. American Forest & Paper Association Page 4 "PliES'(':RIPTlVE fiEsIDENT|i\L’wo6b’bEck CONSTRUCTION aumz Figure 1A. Joist Span - Deck Attached at House and Bearing Over Beam I/—o;:>tlonal overhang existing wall ----— _:][__][::]C::_lL it it it it it ll ll 1| ii it it it it rim joist joist hanger beam (flush,--_-V \ I tight bearing) joist ledger board — -—-—- post / __ LJ/4 maximum_ P overhang " Joist Span (L4): see Table 2 it Figure 1B. Joist Span — Joists Attached at House and to Side of Beam joist existing wall -—->- V fit ii I! II [I it it ii I! ll H H II it beam*--P _---joist hanger ' joist hanger *Note: beam depth must be f equal to or greater than joist ‘edger board "' depth if joist hangers are used M post —-— Joist Span (Lg: see Table 2 it Figure 2. Joist Span — Free Standing Deck /— optional overhang optional overhang—\ “'__1[::][::Ji it it ll II H it it H II I! ll ii'::][::][: --_ rim joist beam -—+-XM \ beam ——-- (flush, tight joist (flush, tight beanng) post bearmg) ii/4 maximuln _‘ Joist Span (LJ): see Table 2 W4 maximum "' overhang’ '54 overhang >1 American Wood Council Page 5 PRESCRIPTIVE RESIDENTIAL W000 becx consrnucnon GUIDE Joists shall not frame in from opposite sides of the same beam. See JOIST-TO-BEAM CONNECTION details, Figure 6. Where multiple 2x members are used, the deck’s beam is assembled by attaching the members identified in Table 3 in accordance with Figure 4. [Table R602.3(l)] Joist Spans (|-J) Less Than or Equal to: , or the joists may attach to the side of BEAM SIZE & ASSEMBLY REQUIREMENTS Deck beam spans shall be in accordance with Table 3 and can extend past the post centerline up to LB/4 as shown in Figure 3. Joists may bear on the beam and extend past the beam centerline up to L;/4 as shown in Figures 1A and 2 Table 3. Deck Beam Spans (LB)1 for Joists Framing from One Side Only the beam with joist hangers as shown in Figure 1B. 18' 16' 14' 12' 10' Size4 Species 2-2x6 2-2x8 2-2x10 2-2x12 3-2x6 Southern Pine 9-11" 12-10" 3-2x8 3-2x10 3-2x12 3x6 or 2-2x6 MONO - No.4 w."1 - 49 Memo - “49 “On. 11 -_ -45 m4MO -_ Home MIT 1. -._./ 5 "0H4 1.. |_mo 6\ 0 1 8X X Q 9..2 2r. F0 00 81 XX 33 S P. 9 U 0 D Fir- Larchz, 3x12 or 2-2x12 MOMUMO .1. ~o'_~D 4 WT? 1.. -.~o~b 3 M/_MOMo ... H4~3~o Momimu .1. H4._../ 5 wlwowo 1.. -_~oT 4 WT? ... 5.-/mo womoml ..1 ~omo-_ 9 0 681 XXX 444 M, Q F,,._ro mPw eSM H R Western 4x12 Cedars, Memo - “45 WW -_ -4..b PF - Homo Nomi -1 HQ]- 6 "0."! - ~07 MONO - ~09 "4wO - T9 68 XX 0.9.. 33 ad me r.R e-, Mae 0.m PP Pine3 3-2x10 12' - O" 10' - 5" 9' - 4" 8‘ - 6" 7' - 10" 7' - 4" 6' - 11" 3-2x12 13'-11" 10‘-9" -9‘-10" Assumes 40 psf live load, 10 psf dead load, L/360 simple span beam deflection limit, L/180 cantilever deflection limit, No. 2 grade, and wet service conditions. lncising assumed for refractory Design values based on northe 12-1" 1. 2. species including Douglas fir~larch, hem-fir, and spruce-pine-fir, rn species with no incising assumed. 3 4i Beam depth must be equal to or greater than joist depth ifjolst hangers are used (see Figure 6, Option 3). optional overhang (may Figure 3: Beam Span Types |- | _ X59 U a w e m m _ 4 _ #5 w d 6 N 8 h | C .H b 8 E a m .m T a m % W S S S C e n \.-./ C C.m B O H +L L pa /\ Sm Ana m i 0. a m S .D D. m a \ M \ _ = l|il_ 3: 16 w T \\ m % 8 | S W % M \.-./ e \_ W U V ‘J0 ( O \\ t n .D W. W M P S m w W m 1 = fimm _ a=W : _ ._ _ M M . . : . 4c V mull . L; 0 mm ll. l American Forest & Paper Association Page 6 iinizscitlerlvi-:' riesinr-ENTIAL W000 nick consrnucnon cum: Figure 4. Beam Assembly Details 10d threaded nail or #10 wood 2 threaded nails or screws at each end or F screw 23" long, staggered in splice end; splices shall be located only over /<—2 rows interior posts (Figure 3)——q\ I f . I . \ ' 0 / I if a beam is constructed with 3-members, _/ 15" attach each outside member to the inside ‘ . * typical member as shown here. DECK FRAMING PLAN A framing plan shows the joist and beam layout; the location of the ledger board, posts, and footings, and the type, size, and spacing of the ledger board fasteners. See Figure 5 for an example of a typical deck framing plan. Figure 5. Typical Deck Framing Plan Lumber species: (see Table 1) ‘ '1 r" :1 r' *1 r "1 I-‘\\Chini‘l1‘eyor Q‘-1 '1 '1 r‘ -1 :3 --X--ledger N Q M \\ Bay Vlfindowk board with 3/1" dia. ‘1’ 5 L “ “““ J boltslla so / h 3 _ O i g rews anc ors #2 = c " " F " F '1 @___" on center a, ‘ =° (see Table 5) (D _,_, ‘2' f’? -‘ M ‘E \ .3 l % °_ _ joisthanger: lbs 7; ll jg in double or triple -N (see Table 3A"“"“) 3 J I 6x6 _ x _ trimmer ~ g Q €‘_\_l post (see Figure 35) trimmer hanger: lbs E / I, \ / "\ (see Table 7) l ' l l i F1 l g. 5 \w / xv’, rim joist it ‘5: . . _-1 5 stair stnngers: cut or solid L round or square footing: see Table 4 ——l ::‘F'i5ur—e‘“2‘8) LB/4 max. (__"clia. or _" x ____") x ___" thick - ____" deep La/4 max. p -4‘ DI>- overhang beam span (Le): see Table 3 overhang lreadsi _ X _ single, double, or triple __ x _; La = _' - _ " (see Tab|e‘6) American Wood Council Page 7 JOIST-TO-BEAM CONNECTION Each joist shall be attached to the beam as shown in Figure 6. Joists may bear on and overhang past the beam a maximum of L1/4. Use Option 1 or Option 2 to attach ‘ the joist to the beam. Option 1 shall only be used if the deck is attached to the house with a ledger (see ' LEDGER ATTACHMENT REQUIREMENTS) or as shown inFigure 23. Mechanical fasteners or hurricane PRESCRIPTIVE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE clips used as shown in Option 2 1nust have a minimum capacity of 100 lbs in both uplift and lateral load directions. Joists may also attach to the side of the beam with joist hangers per Option 3. Joists shall not frame in from opposite sides of the same beam. See JOIST HANGERS for more information. Hangers, clips, and mechanical fasteners shall be galvanized or stainless steel (see MINIMUM REQUIREMENTS). Figure 6: Joist-to-Beam Detail 3~8d threaded OPHON 1* _ OPTION 2“ OPTION 3** toe nails mechamcal (2 on one side, fastener or joist top of beam and joist 1 on the other) humcane crp hang;\ [rengsafigna same "Option 1 M A shall only be / \ D .. used if deck M 0 is attached 2 beam 2 to house 0 **see manufacturer's recommendations for additional requirements mm Figure 7: Typical Joist Hangers Joist hangers, as shown in Figure 7, shall each have a minimum download capacity in accordance with Table 3A. The joist hanger shall be selected from an approved manufacturer’s product data based on the dimensions of the joist or header it is carrying. J oist hangers shall be galvanized or stainless steel (see MINIMUM REQUIREMENTS). Use joist hangers with inside flanges when clearances to the edge of the beam or ledger board dictate. Do not use clip angles or brackets to support joists. Table 3A: Joist Hanger Download Capacity Joist Size Minimum Capacity, lbs 2x8 600 ' 2x10 700 2x12 800 POST REQUIREMENTS All deck post sizes shall be 6x6 (nominal) or larger, and the maximum height shall be 14'-0" measured to the underside of the beam. Posts shall be centered on footings. Cut ends of posts shall be field treated with an approved preservative (such as copper naphthenate) [R402.1.2]. The beam shall be attached to the post by joist hanger with inside flanges notching the 6x6 as shown in Figure 8 or by providing an approved post cap to connect the beam and post as shown in Figure 10. All 3-ply beams shall be connected to the post by a post cap. All thru-bolts shall have washers under the bolt head and nut. Attachment of the beam to the side of the post without notching is prohibited (see Figure 9). ' American Forest & Paper Association Page 8 PRESCRIPTIVE RESIDENTIAL WOODDECK CONSTRUCTION GUIDE Figure 8. Post-to-Beam Attachment Figure 9. Prohibited Post-to-Beam Attachment Requirements Condition (1) 3x or 4x or (2) 2X beam (2) 1/2" dlamelerihru- bolts with washers beam must bear fully on 6x6 6x6 min. notch post to accomodale beam RIM JOIST REQUIREMENTS Attach a continuous rim joist to the ends of joists as shown in Figure 11. Attach decking to the rim joist as shown in Figure 11. For more decking attachment requirements, see DECKING REQUIREMENTS. Figure 10. Alternate Approved Post-to-Beam Post Cap Attachment Solid sawn or mmulti-ply beam Figure 11. Rim Joist Connection Details jcists secure decking to top of rim joist with 10d threaded nails or #10 x 3“ /— minimum wood screws @ 6" 0.0. \ 0 \ . / \‘ ‘ / / ° attach rim joist to end of each joist with ‘Y @ u (3) 10d threaded nails or (3) #10 x 3" V @ minimum wood screws ‘ rlm joist American Wood Council Page 9 FOOTINGS lR403| See Figure l2 and Table 4 for footing size, footing thickness, and post attachment options and requirements. All footings shall bear on solid ground and shall be placed at least 12 inches below the undisturbed ground surface or below the frost line, whichever is deeper. Contact the authority having jurisdiction to determine the specified frost line. Bearing conditions shall be verified in the field by the building official prior to placement of concrete. Where the building official determines that in-place soils with an allowable bearing capacity of less than 1,500 psf are likely to be present at the site, the allowable bearing capacity shall be determined by a soils investigation. DECK FOOTTNGS CLOSER THAN 5 '-0" TO AN EXISTING EXTERIOR HOUSE WALL MUST BEAR AT THE SAME ELEVATION AS THE FOOTING OF THE EXISTING HOUSE FOUNDATION. ' Do not construct footings over utility lines or enclosed meters. Contact local utilities (call 811) before digging. Pre-manufactured post anchors shall be galvanized. See MINIMUM REQUIREMENTS. PRESCRIPTIVE RESIDENTIAL woon DECK CONSTRUCTION eullns; Table 4. Footing Sizes1 Beam Joist Round Square Span, Span Footing Footing Footing LB LJ Diameter Dimension Thickness2 510' 15" g 13" 6" 6' _<_14' 17" 15" 6" ' 518' ' 20" 18" 7" 510' 17" 15" 6" 8' <14‘ 20" 18" 8" 518' 23" 21 " 9" 510' 19" 17" 7" 10' _<_14' 22" 20" 9" 518' 25" 23" 10" - 510' 21" 19" 8" 12' <14‘ 24" 22" 10" 518' 28" 26" 11" 510' 22" 20" 9" 14' <14‘ 26" 24" 11" 518' 30" 28" 12" 510' 24" 22" 9" 16' 514' 28" 26" 12" 518' 32" 30" 13" . 510' 25" 23" 10" 18' 514' 30" 28" 12" 518' 34" 32" 14'' Assumes 1,500 psf soil bearing capacity. 2. Assumes 2,500 psi compressive strength of concrete. Coordinate footing thickness with post base and anchor requirements. Figure 12. Typical Footing Options N posts must be grade :_l l: _l_TJ__l_|I ‘ V/FOUNDATION WALL American Wood Council Page 11 PRESCRIPTIVE RESIDENTIAL W000 becx CONSTRUCTION sums Figure 14. General Attachment of Ledger Board to Band Joist or Rim Board _._1\J exterior sheathing = existing stud wall ———n- existing 2x band joist or 1" minimum \ remove siding at ledger prior to installation threshold carefully flashed and caulked to prevent water intrusion continuous flashing EWP ~ b d extending pastjoist nm oar [——— hanger 2" min. /— deck joist % 1-5/8" min. 5"maX' 1/A2 di t i _ ,, . —— —— " ame er ag Zxfloorjoist, Z‘ 2 mm‘ _ screws or wood l-joist, _/ , “ through-bolts with or MPCWT . , .. washers . ' ‘ - joist hanger existing ——————-I» ' ' ' ‘ - . . ‘ Zxledger board; must be greater foundanon Wa“ l/L than or equal to the depth of the deckjolst and no greater than the depth of the band joist Figure 15. Attachment of Ledger Board to Foundation Wall (Concrete or Solid Masonry) embed anchors per manufacturer /recommendations to resist corrosion and decay, /‘ this area should be caulked ‘i ll /— deck joist ‘ ..' . XF “1/2" diameter ' I . ' approved expansion, A ' epoxy. or adhesive ‘ ‘ anchors with washers 4 ‘ joist hanger L/‘ 2x ledger board; must be greater than or equal to the size of the joist existing concrete --'>» or solid masonry wail Figure 16. Attachment of Ledger Board to Foundation Wall (Hollow Masonry) embed anchors per manufacturer to resist corrosion and decay, this area should recommendations ‘ be caulked . . deck joist existing hollow ll , masonry wa 1/2" diameter approved epoxy or adhesive b k ll fii d ICC Ce S ' e anchors with washers with grout or concrete at ‘ I anchor locations joist hanger (new Construction) l<——>-I 2x ledger board; must be greater 8" block wall than or equal to the size of the joist minimum American Forest & Paper Association Page 12 ' PRESCRIPTIVE RESIDENTIALWOOD DECK CONSTRUCTIONGUIDE PROHIBITED LEDGER ATTACHMENTS deck shall be free-standing (see FREE-STANDING . Attachments to exterior veneers (brick, masonry, stone) DECKS). and to cantilevered floor overhangs or bay windows are prohibited (see Figures 17 and 18). In such cases the t Figure 17. No Attachment to or Through Figure 18. No Attachment to House Overhang Exterior Veneers (Brick, Masonry, Stone) --—'\. deck joist <—brick __ veneer or masonry _ ==~_-1 chimney LEDGER BOARD FASTENERS nominal lumber band joist (1-1/2" actual) or EWP rim Only those fasteners noted below are permitted. LEAD board bearing on a sill plate or wall plate shall be ANCHORS ARE PROHIBITED. _ constructed with ‘/z" lag screws or bolts with washers per Table 5 and Figure 19 (see MINIMUM Deck ledger connection to band joist or rim board. REQUIREMENTS). The connection between a deck ledger and a 2-inch Table 5. Fastener Spacing for a Southern Pine, Douglas Fir-Larch, or Hem-Fir Deck Ledger and a 2-inch Nominal Solid-Sawn Spruce-Pine-Fir7'3 Band Joist or EWP Rim Board8 (Deck Live Load = 40 psf, Deck Dead Load = 10 psf)3'6 Rim Board 6‘-0" 6'-1" 8'-1" 1 0'-1" 12'-1" 14'-1" 16'-1" Joist Span . or and to to to to to to Band Joist less 8'-O" 10'-0" 12'-0" 14'-0" 16'-0" 18'-0" Connection Details On-Center Spacing of Fasteners"’5 ,, . . 1" EWP6 24" 18" 14" 12" 10" 9" 8" 11/?’ 1-1/8" 28" 21" 16" 1411 12" 10" 911 32 9 1-1/2" Lurnber:/D9 30" 23!! 18" 15" 13" 11" 10" ,, . . 1" EWF>8 24" 18" 14" 12" 10" 9" “ 15 1/2,, d'a".‘e*e' bolt with 1-1/8" EWP6 28" 21" 16" 14" 12" 10" 8" /32 maximum sheathmg H/2,, Lumber”, 36.. 36.. 34.. 29.. 24.. 21.. 19.. 1/2" diameter bolt with 1" EWP6 24" 18" 14" 12" 10" 9" 8" 15/32" maximum sheathinzg and 1-1/B" EWP6 28" 21" 16" 14" 12" 10" 9" 1/2" stacked washers '8 1-1/2" Lumbefl-9 36" 36" 29" 24" 21" 18" 16" The tip of the lag screw shall fully extend beyond the inside face of the band joist. . The maximum gap between the face of the ledger board and face of the wall sheathing shall be 1/2". Ledgers shall be flashed or caulked to prevent water from contacting the house band joist (see Figures 14, 15, and 16). Lag screws and bolts shall be staggered per Figure 19. Deck ledgers shall be minimum 2x8 pressure-preservative-treated No.2 grade lumber, or other approved materials as established by standard engineering practice. 6 When solid-sawn pressure-preservative-treated deck ledgers are attached to engineered wood products (minimum 1" thick wood structural panel band joist or structural composite lumber including laminated veneer lumber), the ledger attachment shall be designed in accordance with accepted engineering practice. Tabulated values based on 300 lbs and 350 lbs for 1" and 1-1/8" EWP rim board, respectively. A minimum 1"x9‘/2" Douglas fir-larch laminated veneer lumber rim board shall be permitted in lieu of the 2" nominal band joist. 8 Wood structural panel sheathing, gypsum board sheathing, or foam sheathing not exceeding one inch thickness shall be permitted. The maximum distance between the face of the ledger board and the face of the band joist shall be one Inch. 9 Fastener spacing also applies to southern pine, Douglas fir-larch, and hem—fir band joists. American Wood Council Page 13 PRESORIPTIVE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE Placement of lag screws or bolts in deck ledgers the deck ledger (see Figure l9). Proper installation of lag The lag screws or bolts shall be placed as shown in screws or bolts shall be verified by the authority having Figure 19. The lag screws or bolts shall be staggered jurisdiction. from the top to the bottom along the horizontal run of Figure 19: Ledger Board Fastener Spacing and Clearances See Table 5 §,§"2g§§V"V;aS‘e“e's See Figure 14 for rim -—I> ="-~ ioist fastener spacing @ @ @--_ F 5-5: min. for 2X8.* *Distance can be reduced to 4.5" 5" max. _ I 6-5" ml". for 2X10 if lag screws are used or bolt @) @ 7-5 mm for 2X12 spacing is reduced to that of , l . l lag SCi’8\tlVS2lO8all3l8C2 2x8t (1/2 ,, ——-D-i—--l—— L ' ie ers o x an ‘ois s " 2 mm‘ ledger gangczgzex/"ih:h\L:':;;& or ' 314" min, stagked washers notJ permitted) Thm-Bolts Minimum spacing and embedment length shall be per Thru-bolts shall have a diameter of 1/2". Pilot holes for. the manufacturer’s recommendations. All anchors must thru-bolts shall be 17/32" to 9/16" in diameter. Thru-bolts have washers. require washers at the bolt head and nut. _ Lag Screws ' Expansion and Adhesive Anchors Lag screws shall have a diameter of 1/2" (see MINIMU Use approved expansion or adhesive anchors when ' REQUIREMENTS). Lag screws may be used only when attaching a ledger board to a concrete or solid masonry the field conditions conform to those shown in Figure wall as shown in Figure 15 or a hollow masonry wall 14. See Figure 20 for lag screw length and shank with a grouted cell as shown in Figure 16. Expansion requirements. All lag screws shall be installed with and adhesive anchor bolts shall have a diameter of ‘/2". washers. Figure 20: Lag Screw Requirements lag screws must be hot- dipped galvanized or stainless steel only screw must penetrate beyond band board 1-1/2" shank length must extend through a minimum of 1/2.. (no threads) existing band board Lag screw installation requirements: Each lag screw The threaded portion of the lag screw shall be inserted shall have pilot holes drilled as follows: 1) Drill a 1/2" into the pilot hole by turning‘. DO NOT DRIVE LAG diameter hole in the ledger board, 2) Drill a 5/16" SCREWS WITH A HAMMER. Use soap or a wood- diameter hole into the band board of the existing house. compatible lubricant as required to facilitate tightening. DO NOT DRILL A ‘/2" DIAMETER HOLE INTO THE Each lag screw shall be thoroughly tightened (snug but BAND BOARD. not over-tightened to avoid wood damage). American Forest & Paper Association Page 14 E m U G N m W-I cc LU "R LT S ,N 0 C ,K C E- D D 0 0 w I- M -I N E m S E R E.- W ,_| 5... LR c 5 E- R P. FREE—STANDING DECKS EXISTING HOUSE FOOTING IF LOCATED Decks which are free-standing do not utilize the exterior eumm Qucw 90 whvm Qt .mm.m efn m.su tam E 0* .1 same elevation as existing house footing »—deck footings must be at CLOSER THAN 5'-O" TO AN EXISTING HOUSE WALL (see Figure 2 and Figure 12). For houses with basements, a cylindrical footing (caisson) is recommended to minimize required excavation at the basement wall. Beam size is determined by Table 3. wall of the existing house to support vertical loads (see Figure 21); instead, an additional beam with posts is provided at or within L/4 of the existing house. THE ASSOCIATED DECK POST FOOTINGS SHALL BE PLACED AT THE SAME ELEVATION AS THE Figure 21. Free-Standing Deck DECK STABILITY Decks greater than 2 feet above grade shall be provided with diagonal bracing. Figure 22. Diagonal Bracing Requirements provide blocking when joists do not align with posts m 8 G b '2x4, typical thru-bolt with washers, typical BRACING PARALLEL TO BEAM BRACING PERPENDICULAR TO BEAM American Wood Council Page 15 Diagonal Bracing: Provide diagonal bracing both parallel and perpendicular to the beam at each post as shown in Figure 22. When parallel to the beam, the bracing shall be bolted to the post at one endand beam at the other. When perpendicular to the beam, the bracing shall be bolted to the post at one end and a joist or blocking between joists at the other. When a joist does not align with the bracing location, provide blocking between the adjacent joists. Decks attached to the house as shown in Figure 23A do not require diagonal bracing perpendicular to the house. Diagonal bracing parallel to the house may be omitted at the beam adjacent to the house for a free-standing deck attached as shown in Figure 23. ' F ree-standing Deck - Attachment to House: Attach the deck rim joist to the existing house exterior wall as shown in Figure 23 for a free-standing deck. The wall must be sheathed with minimum 3/8" wood structural panel sheathing. Use lag screws or thru-bolts when fastening to an existing band joist or wall stud; use expansion anchors or epoxy anchors when fastening to . PRESCRIPTIIIE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE 7 concrete or masonry. DO NOT ATTACH TO BRICK VENEERS. VERIFY THIS CONDITION IN THE FIELD PRIOR TO UTILIZING THIS METHOD. Fasteners shall be l6H on center and staggered in 2 rows for free-standing decks. Flashing over the rim joist is required and must be installed in accordance with the flashing provisions in the LEDGER ATTACHMENT REQUIREMENTS. Deck Supported by Ledger - Attachment to House: Where supported by attachment to an exterior wall (Figures l4, 15, or 16), decks shall be positively , anchored to the primary structure and designed for both vertical and lateral loads as applicable [R502.2.2]. The lateral load connection required shall be permitted to be in accordance with Figure 23A. Hold down tension devices shall be provided in not less than two locations per deck, and each device shall have an allowable stress design capacity ofnot less than l,500 lb [R502.2.2.3]. See the Commentary to this document for additional information on applicability of this provision. Figure 23. Attachment of Free-Standing Deck to House for Deck Stability exmor sham“ _ “ " remove siding at rim joist. min Wckness = 3/8,, ' K location prtorto Installation continuous flashing extending existing wall stud, band --—-—-0» X 5 past "m M“ fasleners joist, or concrete or masonry foundatlon wall fasteners @ 16" o.c. staggered GUARD REQUIREMENTS All decks greater than 30" above grade are required to have a guard [R3 12.1] - one example is shown in Figure Figure 23A. Example of a Lateral Load Device for a Deck Attached to a House with a Ledger __r floor sheathing nalllng at 6" maximum on center to joist with hold down \ hold down or similar tension device floor joist -I 24. Other methods and materials may be used for guard construction when approved by the authority having jurisdiction. Figure 24. Example Guard Detail 4x4 post, typical l ~ 2x6 or 5/4 board 2 l 7 00 nor NOTCH t rall cap I >~ 2x4 top and bottom; attach to guard post with (2)8d threaded nails or . ..ti (2)#8 wood screws Z2-’/1" long on inside face (2)112“ diameter-74 \LOpenings sha" not allow \\-attach batusters attop and bottom ltrru-bolts and h the passage of a 4" was 6'5 diameter sphere with (1)#B wood screw or (2)8d post~frame threaded nails with - 0.135" nominal diameter American Forest & Paper Association Page 16 PiiESCRIPiIE"'RiE'iDEN1'lAL W6ob DECK CbNSTRU(STI6N GUIBE " GUARD POST ATTACHMENTS joists shall be attached to the rim joist in accordance Deck guard posts shall be a minimum 4x4 (nominal) with Figure 26. Only hold down anchor models meeting with an adjusted bending design value not less than these minimum requirements shall be used. Hold down 1,100 psi. anchors shall have a minimum allowable tension load of _ 1,800 pounds for a 36" maximum rail height and be Guard posts for guards which run parallel to the deck installed in accordance with the manufacturer’s joists shall be attached to the outside joist per Figure 25. instructions. Guard posts for guards that run perpendicular to the deck Figure 25. Guard Post to Outside Joist Example see FlGURE 24 for guard *guard posts can be installed as component attachment shown in Figure 26 (between joists) guard Posts may be requirements if blocking is installed as shown below located on either side of the outside_joiSt within 12 of €8ChSld8 of the post guard post—-—-- with hold-down anchors; attach blocking with 10d at first interior bay, provide 2x blocking at guard posts threaded nails top and bottom, each side /\_‘/\ (2)1/2" dla. thru— bolts and washers outside-joist-_-> Min‘ M7 3; I‘ . 2-1/2" min. and 5" max. s- .2"min. 3"‘ ~ d >* t 0utslde-joist-/ SECTION Qua‘ P05 PLAN WEW Figure 26. Guard Post to Rim Joist Example see FlGURE 24 for guard -5 holddown anchor component attachment '1 j bists requirements i 1 d t .. uar os guard post _.-_ i align guard 9 p I post at joist l tocations 1 .. ._ rim joist j S "= hold-down anchor . K rim joist it a rim joist joist———— E ‘J ' - " 1Ti 2" _ hold-down anchor/I mmimum (2)1/2 \ @ = ,a mill _ “ diameterthru- ¢2-1/2 mm. and5 max. bolts and washers = F 2" min. at joist location between joists SECTION PLAN VIEWS American Wood Council Page 17 STAIR REQUIREMENTS Stairs, stair stringers, and stair guards shall meet the requirements shown in Figure 27 through Figure 34 and Table 6 except where amended by the local jurisdiction. All stringers shall be a minimum of 2x12. Stair stringers shall not span more than the dimensions shown in Figure 28. If the stringer span exceeds these dimensions, then a 4x4 post may be provided to support the stringer and shorten its span length. The 4x4 post shall be notched and bolted to the stringer with (2) 1/2" diameter through- bolts with washers per Figure 8. The post shall be centered on a 12" diameter or 10" square, 6" thick footing. The footing shall be constructed as shown in Figure 34 and attached to the post as shown in Figure 12. An intermediate landing may also be provided to shorten PRESORIPTIVE RESIDENTIAL woon necx consrnucnou euro: the stringer span (see provisions below). If the total vertical height of a stairway exceeds 12'-O", then an intermediate landing shall be required. All intermediate stair landings must be designed and constructed as a free-standing deck using the details in this document. Stairs shall be a minimum of 36" in width as shown in Figure 33 [R31 1.7]. If only cut stringers are used, a minimum of three are required. For stairs greater than 36" in width, a combination of cut and solid stringers can be used, but shall be placed at a maximum spacing of l8" on center (see Figure 29). The width of each landing shall not be less than the Width of the stairway served. Every landing shall have a minimum dimension of 36" measured in the direction of travel and no less than the width of the stairway served [R3 ll.7]. Figure 27. Tread and Riser Detail riser may be open, but shall not allow the passage of a 4" diameter sphere 10" minimum \:j - tread width r ‘3 7-3/4" maximum ' riser; height Sm“ —-<—— risers‘ ix material minim not deviate from . - . l._..._..___._ one another by more than 3/8" \— treads: see Figure 29 and Table 6 3/4" — 1-'1/4" nosing; nosing ' shall not deviate from one another by more than 318" Figure 29. Tread Connection Requirements Attachment per tread at each stringer or ledger: 3x__ treads - (2)16d threaded nails or (2)#8 screws 23-1/2" long 2x_ or 5/4 treads - (2)8d threaded nails or (2)#8 screws 22-1/2" long um stringer ----- ~- treads: 2x__ or 5/4 board I treads: see Table 6 18" max >3; 18" max , Al: 35" max /1 -\\/ /u stringers -/ CUT STRINGER SOLID STRINGER ' / 2x4 ledgers, each side. full depth of tread; attach with (4)10d threaded nails or (4)#8 wood screws 23" long Figure 28. Stair Stringer Requirements max. span = 7’-0" for southern pine Fan span = 6'-O" for other Table 1 species ' CUT STRlNGER __ max. span = 16‘-6" for southern pine * max. span = 13'-3" for other Table 1 specg SOLID STRINGER Table 6. Minimum Tread Size for Cut and Solid Stringers1 Species Cut Solid Stringer Stringer Southern Pine 2x4 or 5/4 2x6 Douglas Fir Larch, Hem-Fir, ser2 2x4 or 5/4 2x8 or 3x4 Redwood, Western Cedars, Ponderosa Pinea, Red Pine3 2x4 or 5/4 2x10 or 3x4 1. Assumes 300 lb concentrated load, L/288 deflection limit, No. 2 grade, and wet service conditions. 2. lncising assumed for refractory species including Douglas fir- larch. hem-fir, and spruce-pine-fir. 3. Design values based on northern species with no incising assumed. ‘ American Forest & Paper Association Page 18 Figure 30. Stair Guard Requirements 6'-O" maximum between posts I stair guard is required for stairs with a total rise of 30" or more; see GUARD ' REQUIREMENTS for more information stair guard height: 34" min. measured from nosing of step Openings for required guards on the Triangular opening shall sides of stair treads shall not allow not permit the passage a sphere 4-3/8" to pass through. of a 6" diameter sphere. PRESCRIPTIVE RESIDENTIAL WOOD DECK CONSTRUCTION GUIDE Figure 31. Stair Stringer Attachment Detail rim joist or outside joist 3 1| \ _ l sloped joist hanger, -/ minimum download capacity of 625 lbs; see JOlST HANGERS for more requirements ATTACHMENT WlTH HANGERS STAIR HANDRAIL REQUIREMENTS All stairs with 4 or more risers shall have a handrail on at least one side (see Figure 32A) [R3ll.7.7]. The handrail height measured vertically from the sloped plane adjoining the tread nosing shall be not less than 34 inches and not more than 38 inches (see Figure 30) [R3 11.7.7.1]. Handrails shall be graspable and shall be composed of decay-resistant and/or corrosion resistant material. Handrails shall be Type I, Type II, or provide equivalent graspability (see Figure 32B). Type I shall have a perimeter dimension of at least 4" and not greater Figure 32A. Handrail Mounting Examples Fasten handrails per manufacturer recommendations 34"-38" to nosing of stairs, typical wall --_> —--——— guard ‘~ Corrosion-resistant h ndrall ha dware - post ____;\I___ 3 r MOUNTED T O GUARD MOUNTED T0 WALL than 6—%''. Type II rails with a perimeter greater than 6~1/1" shall provide a graspable finger recess area on both sides of the profile [R31 1.7.7.3]. All shapes shall have a smooth surface with no sharp corners. Handrails shall run continuously from a point directly over the lowest riser to a point directly over the highest riser and shall return to the guard at each end (see Figure 33). Handrails may be interrupted by guard posts at a turn in the stair [R31 1.7.7.2]. Figure 32B. Handrail Grip Size CIRCULAR NONCIRCULAR [R31 1.7.73 Type 1] Perimeter: 4" - 6}" RECESSED [R31 1.7.7.3 Type ll] Perimeter: >6;l" American Wood Council Page 19 PRESCRITIVE RESIDENTIAL woon DECK CGNSTRUG'I'lON euIuE Figure 35: Detail for Framing Around a Chimney or Bay Window a = 3i_Or- maximum triple joist d k‘ y _ , ' i ec mg ma i____ 6‘-O" max|mum_-j (Tagglzrgypica extend 6" maximum ’ i-———l;_j Z Chimney or % -1 r chiggney F-M WWW % bay window / \ ledger \cNIindgw © © Burns or '29" f "Y // so ews s a u /////x /////7 J board HT @ @ extend into band “ 1 1 ' ' tor rim board it r it \ s mp|e trimmer —double joist dome header \\~(2)‘/2" diameter thru-bolt joist each side* haliéieriti/iJi<1"=iI or lag screws at ledger* *Trimmer joist may be double if joists are spaced ‘ *See Figure 19 for fastener spacing, 24'' 0c. or if trimmer length is 8‘-6" or less edge, and end distances PLAN VIEW SECTION American Wood 7: Cuncil Trad/tiona/ and Engineered Wood Products INTERNATIONAL CODE COUNCll.°’ It is intended that this document be used in conjunction with competent design, accurate fabrication, and adequate supervision of construction. While every effort has been made to insure the accuracy ofthe information presented, the American Forest & Paper Association and its members do not assume responsibility for errors or omissions in the document, nor for designs, plans, or construction prepared from it. Those using this document assume all liability arising from its use. Copyright © 2007, 2009, 2010 American Forest & Paper Association, lnc. American Wood Council Page 20 STAIR FOOTING REQUIREMENTS lR403l Where the stairway meets grade, attach the stringers to _ . -.lh6§taiI guard posts,as,,shown.in Figure 34. Posts shalliE4 bear on footings. All footings shall bear on solid ground and shall be placed at least 12 inches below the undisturbed ground surface or below the frost line, whichever is deeper (see Figure 34). Stringers shall bear on a 2x4 bearing block attached to the post as shown. Stringers shall not bear on new or existing concrete pads or patios that are not founded below this depth. When guards are not required (see GUARD PRESCRIPTIVE RESIDENTIAIL WOOD DECK CONSTRUCTION GUIDE Figure 33. Miscellaneous Stair Requirements REQUIREMENTS), posts may terminate below the bottom tread elevation. Bolts are only required if a guard post is required. i i STAIR LIGHTIHH V I Stairways shall have a light source located at the top landing such that all stairs and landings are illuminated. The light switch shall be operated from inside the house. However, motion detected or timed switches are acceptable. Figure 34. Stair Footing Detail : handrail 9“ \ handrail shall return at each end 36'' min. stair wid@ I I I I V I I I FRAMING AT CHIMNEY OR BAY WINDOW All members at a chimney or bay window shall be framed in accordance with Figure 35. Headers may span a maximum of 6'-()''. When a chimney or bay window is wider than 6'-O", one or more 6x6 posts may be added to reduce header spans to less than 6‘-()‘‘. In such cases, the post footing must meet the requirements in the FOOTINGS section. Headers with a span length greater than 6'-0" require a plan submission. Headers shall be located no more than 3‘-0" from the end of the trimmer joist. Triple trimmer joists are required on each side of the header if joist spacing is 12" or 16" o.c. or if the trimmer joist span exceeds 8'-6"; otherwise, double trimmer joists are permitted. Trimmer joists may bear on the beam and extend past the beam centerline up to L;/4 as shown in Figures 1A and 2, or the trimmer joist may attach to the side of the beam with j oist hangers as shown in Figure out post at bottom tread elevation when no stair guard is required (2)‘/z" diameter thru-bolts with washers required only if guard is required; otherwise —-1/L— use (2) #8 wood screws 23-1/1" long or (2) 16d threaded nails Attach 2x4 bearing block using (8) #8 wood screws 23-‘/2" long or (8) ‘l6d th_re_aded nails Z1? + er 6" \ minimum P V \ secll n d 10"x16"squar

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