SHEAR BRACE. Featuring ilevel Shear Braces for Engineered and Prescriptive Applications iLevel8 (

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1 WALL SOLUTIONS SHEAR BRACE 2006 IBC/IRC Code Accepted* *Achieved code evaluation report recognition (ICC ES ESR-2652) for compliance with the 2006 IBC/IRC Featuring ilevel Braces for Engineered and Prescriptive Applications Engineered for Performance Designed for Safety Built for Wood Structures Compatible with IRC Bracing Requirements Perfect for Narrow Wall Sections Quick and Easy Installation with Anchor Bolt Kit Limited Product Warranty #TJ-8620 SPECIFIER S GUIDE iLevel8 ( )

2 ilevel SHEAR BRACE WHAT IS AN ilevel SHEAR BRACE? The ilevel Brace (isb) is a specially designed, prefabricated, engineered-wood panel that helps homes resist lateral forces such as those created by earthquakes and high winds. The International Residential Code (IRC) and International Building Code (IBC) require wall bracing for lateral loads in all residential structures. The ilevel Brace can help you meet these requirements efficiently and confidently with the following features: Can be used in prescriptive specification or engineered design Narrow panel widths have high allowable loads Tall wall and multistory applications Field adjustable can be trimmed and drilled 2 TABLE OF CONTENTS ilevel Brace Descriptions 2 3 Kit Descriptions 4 Engineered Design General Assumptions 5 Design Loads Standard Brace 6 Design Loads Braces on Raised Floor Kits 7 Portal Frame Assembly 8 Portal Design Information 8 Design Loads Portal Frame 9 Design Loads Stacked Braces 10 Overturning Forces 11 Installation Details, Trim Zones, and Holes 12 Raised Floor Details 13 Portal Installation Details 14 Multistory Kit Installation Details 15 Anchorage Embedment Depth 16 Alternate Anchorage for 12" Braces 16 Anchor Bolt Installation 17 Anchorage Details Prescriptive Specification Wall Bracing 20 How to Prescriptively Specify Braced Panels 20 Prescriptive Bracing Requirements 21 Prescriptive Brace Example 21 Portals 22 Portal Header Sizing Table 22 Prescriptive Anchorage 23 Alternate Anchorage for 12" Braces 23 12" braces up to 9' tall and all 18" braces can be substituted, 1-for-1, for any field-built, prescriptive brace panel Available ilevel Braces Brace (1) Width Height (2) Trimmed Minimum Height isb 12x7 12" 78" 741/2" 90 Yes Portal isb 12x7.5 12" 851/2" 82" 95 Yes Portal isb 12x8 12" 931/4" 89¾" 105 Yes Portal isb 12x9 12" 1051/4" 78" 115 Standard (2) isb 12x10 12" 1171/4" 78" 125 Standard (2) isb 12x11 12" 1291/4" 78" 140 Standard (2) isb 12x12 12" 1411/4" 78" 150 Standard (2) isb 12xCustom 12" 78" 1411/4" (3) 78" Varies Standard (2) isb 18x7 18" 78" 741/2" 130 Yes Portal isb 18x7.5 18" 851/2" 82" 140 Yes Portal isb 18x8 18" 931/4" 89¾" 150 Yes Portal isb 18x9 18" 1051/4" 78" 170 Standard (2) isb 18x10 18" 1171/4" 78" 185 Standard (2) isb 18x11 18" 1291/4" 78" 205 Standard (2) isb 18x12 18" 1411/4" 78" 220 Standard (2) isb 18xCustom 18" 78" 1411/4" (3) 78" Varies Standard (2) isb 18xCustom STK 18" 931/4" 1411/4" (4) N.A. (4) Varies Stacked (5) isb 24x8 24" 931/4" 89¾" 200 Standard isb 24x9 24" 1051/4" 89¾" 225 Standard isb 24x10 24" 1171/4" 89¾" 250 Standard isb 24x11 24" 1291/4" 89¾" 270 Standard isb 24x12 24" 1411/4" 89¾" 295 Standard isb 24xCustom 24" 931/4" 1411/4" (3) 89¾" Varies Standard isb 24xCustom STK 24" 931/4" 1411/4" (4) N.A. (4) Varies Stacked (5) (1) 12" Brace may only be used in first story applications. 18" and 24" braces may be used in first and second story applications. (2) 12" and 18" braces may be used as a portal brace if trimmed to a height of 78" 931/4". (3) Custom heights are available in 1 8" increments. (4) Order to the nearest 1 8" of the required height. First-story braces in stacked applications may NOT be trimmed. If used in non-stacked applications, braces may be trimmed; 78" minimum height required for 12" and 18" braces, and 89¾" minimum height required for 24" braces. (5) A stackable (STK) brace is required as the bottom brace in a stacked-brace application. Available Kits (see page 4 for parts list) Anchor kits: Required for all braces except braces in second story applications. Raised floor kits (RFK): Required when installing brace on a raised floor using detail SB8. Not required for SB9. See page 13 for details. Portal kits: Required for brace-to-header connections. Multistory kits (MSK): Required for stacked-brace applications. Weight Code Evaluation: See ICC ES ESR-2652 Portal Kit (Included with Brace) ilevel Brace Specifier s Guide TJ-8620 January 2009 Brace Type Brace Naming System isb 18x8-STK Stackable Nominal height (ft) Width (in.) ilevel Brace

3 ilevel SHEAR BRACE DESCRIPTIONS Standard Brace Tall Wall Brace Portal Brace Stackable Brace Standard Brace isb Standard brace ilevel Braces are trimmable in most applications. See page 12 for details. Convenient access for wiring Field drillable and trimmable Simple connection Easy header connections Resists bowing, twisting, and shrinking MSK for stacked applications, includes upper holdowns Lower brace must be STK-designated, stackable brace isb Standard Brace Narrow wall spaces Top brace in two-story applications Balloon framing isb Portal Brace Narrow wall spaces Garages Large windows and doors isb Stackable Brace Narrow wall spaces Bottom brace in two-story applications Multi-story installation kit available (order seperately) ilevel Brace Specifier s Guide TJ-8620 January

4 KIT DESCRIPTIONS Anchor Kits Required for all braces except braces in second-story applications. Kit includes two jam nuts, two double nut and washer assemblies, two bolt holders, and one anchor bolt spacer (specify width). Order threaded rod separately. Anchor Bolt Spacer Length (1) Bolt Holder Diameter Nut Thread Size Washer Type " 7 8" 9 UNC 2" Square/Round 18" 7 8" 9 UNC 2" Square/Round 24" 1" 8 UNC 2" Round (1) Flat anchor bolt spacers are available in " and 18" lengths for CMU and Epoxy Anchor applications. Anchor Kit Naming System Anchor Kit 18 Brace width (in.) Kit name Raised Floor Kits (RFK) Required when installing brace on a raised floor using detail SB8. Kit includes two threaded rods (length precut to match floor system depth), two steel shims, two ported couplers, one TimberStrand LSL block with metal plates top and bottom, and one USP MP4F framing anchor. See page 13 for installation details. For use with 12" and 18" braces only. First Floor Joist Depth 9 1/2" 16" Overall Width Brace width + 3" Available for 12" isb Available for 18" isb Available for 24" isb Yes Yes No RFK Naming System Raised Floor Kit 18x91/2 Floor joist depth (in.) Brace width (in.) Kit name Portal Kits Required for brace-to-beam connections. Kit includes four ilevel straps and comes standard with portal braces. Order the kit seperately if using standard braces in a portal application. Multistory Kits (MSK) Required for stacked-brace applications. Kit includes two threaded rods (length pre-cut to match floor system depth), two holdowns with welded-on nuts, two bearing plates, two nuts, nail-gun nails, one T-plate, and three USP MP4F framing anchors. See page 15 for installation details. For use with 18" and 24" braces only. Second Floor Available for Available for Available for Joist Depth 12" isb 18" isb 24" isb 9 1 2" 16" No Yes Yes MSK Naming System MultiStory Kit 18x91/2 Floor joist depth (in.) Brace width (in.) Kit name 4 ilevel Brace Specifier s Guide TJ-8620 January 2009

5 ENGINEERED DESIGN GENERAL ASSUMPTIONS Design Assumptions for ilevel Braces ilevel Braces meet the Acceptance Criteria for Prefabricated Wood Panels (ICC-ES AC 130). ilevel Brace design values are consistent with typical wood-framed construction. Use the following values when designing: Building Code R Ω C d 1997 UBC N.A IBC and 2006 IBC All table values throughout this bulletin are based on concrete with f' c of 2,500 psi. Install products according to this specifier's guide. Changes in installation methods or modification to the product and associated systems (other than those indicated in this guide) should only be made by a design professional of record. Altered installation procedures and the performance of modified products are the sole responsibility of the design professional of record. The building shall be designed in accordance with the appropriate building code and meet local, state, and federal requirements. Verify design requirements with the local building official. Concrete foundation design remains the responsibility of the design professional of record. ilevel Braces are part of the overall lateral-force-resisting system of the structure. The design of this system, including a complete load path necessary to transfer lateral forces from the structure to the ground, is the responsibility of the design professional of record. AC130 cyclic testing in the lab. 7 8" anchor bolt holder and " wrench for 12" and 18" isbs 1" anchor bolt holder and 11/2" wrench for 24" isbs ilevel Brace Specifier s Guide TJ-8620 January

6 ALLOWABLE DESIGN LOADS STANDARD BRACE Design Loads (1) Standard Brace on Concrete Foundation Brace (2) Width Height Total Vertical Load Seismic Design Drift at (in.) Holdown Uplift at (3) Wind Design Drift at (in.) Holdown Uplift at (3) isb 12x8 12" 931/4" 4, , ,280 isb 12x9 12" 1051/4" 4, , ,370 isb 12x10 12" 1171/4" 4, , ,795 isb 12x11 12" 1291/4" 4, , ,755 isb 12x12 12" 1411/4" 4, , ,555 isb 18x8 18" 931/4" 8,000 2, ,910 2, ,200 isb 18x9 18" 1051/4" 8,000 1, ,530 2, ,750 isb 18x10 18" 1171/4" 8,000 1, ,640 1, ,905 isb 18x11 18" 1291/4" 8,000 1, ,360 1, ,600 isb 18x12 18" 1411/4" 8,000 1, ,830 1, ,015 isb 24x8 24" 931/4" 8,000 4, ,800 4, ,685 isb 24x9 24" 1051/4" 8,000 3, ,680 4, ,550 isb 24x10 24" 1171/4" 8,000 3, ,720 3, ,505 isb 24x11 24" 1291/4" 8,000 3, ,685 3, ,475 isb 24x12 24" 1411/4" 8,000 2, ,305 2, ,035 (1) Interpolation of design values is allowed for custom height braces. For braces less than 931/4" tall, use the values for a 931/4" tall brace. (2) 12" wide braces, 1051/4" tall and less, and all 18" wide braces are allowed in prescriptive applications. (3) Holdown Uplift at is based on an assumed moment-arm equal to the brace width minus 2". Design Loads table is based on: 160% load duration. No further increases for duration of load are permitted. isb height of 89¾" to 1411/4". ASTM A449 or ASTM A193-B7 threaded rod for anchorage; 1" diameter for 24" wide braces, 7 8" for all others. See page 16 for other options. Vertical Loads Front View Loads Out-of-Plane Lateral Loads (PSF) Attached to Double Top Plate (1) Brace Standard Brace Height Width 8' 9' 10' 11' 12' 12" " " " Attached to Header (1)(2)(3) 18" " (1) Based on 160% load duration. No further increases for duration of load are permitted. (2) Table values based on using ilevel Portal Kit to resist header overturning. (3) Load reduction factors: 16" deep headers = " deep headers = 0.78 Vertical Loads Out-of-Plane Lateral Loads (psf) Out-of-Plane Lateral Loads table is based on: Braces used in a standard application with or without a Raised Floor Kit and installed according to the details in this guide. Wall deflection of L/240. Header depth of 14". Out-of-plane lateral loads consider the total vertical load. Side View 6 ilevel Brace Specifier s Guide TJ-8620 January 2009

7 ALLOWABLE DESIGN LOADS BRACES ON RAISED FLOOR KITS (RFK) Design Loads (1) Standard Brace on Raised Floor Kit Brace (2) Width Height Total Vertical Load Seismic Design Drift at (in.) Holdown Uplift at (3) Wind Design Drift at (in.) Holdown Uplift at (3) isb 12x8 12" " 4, , ,360 isb 12x9 12" " 4, , ,990 isb 18x8 18" " 8,000 2, ,800 2, ,985 isb 18x9 18" " 8,000 1, ,985 1, ,085 isb 18x10 18" " 8,000 1, ,810 1, ,890 isb 18x11 18" " 8,000 1, ,480 1, ,425 isb 18x12 18" " 8, , ,725 (1) Interpolation of design values is allowed for custom height braces. For braces less than 931/4" tall, use the values for a 931/4" tall brace. (2) 12" wide braces, 1051/4" tall and less, and all 18" wide braces are allowed in prescriptive applications. (3) Holdown Uplift at equals the uplift generated from the shear brace plus the uplift generated from the raised floor kit. Uplift numbers do not include any consideration of shear from the floor diaphragms; this check is the responsibility of the design professional of record. Holdown uplift at allowable shear is based on the following assumptions: Brace: moment arm = brace width minus 2". Raised Floor Kit: moment arm = RFK width minus 31 2". Vertical Loads Loads Design Loads table is based on: 160% load duration. No further increases for duration of load are permitted. isb height of 89¾" to 1411/4" (not including RFK). ASTM A449 or ASTM A193-B7 threaded rod for anchorage; 1" diameter for 24" wide braces, 7 8" for all others. See page 16 for other options. All kits use 31/2" wide TimberStrand LSL blocks with pre-installed steel plates. For floor systems 91/2" to 16" deep: RFK height = joist height + 21/4" (assuming a 11/2" sill plate and ¾" floor sheathing) RFK width = shear brace width + 3" As an alternative to using the RFK, attach braces directly to concrete (as in detail SB9 on page 13). Use the Design Loads Standard Brace on Concrete Foundation table on page 6 with this detail. RFKs are for use only in single-story, non-portal applications. Front View Vertical Loads Out-of-Plane Lateral Loads (1) (PSF) Attached to Double Top Plate Brace Standard Brace Height Width 8' 9' 10' 11' 12' 12" " (1) Based on 160% load duration. No further increases for duration of load are permitted. Out-of-Plane Lateral Loads (psf) Out-of-Plane Lateral Loads table is based on: Braces used in a raised floor application installed according to the details in this guide. Wall deflection of L/240. Out-of-plane lateral loads consider the total vertical load. Side View ilevel Brace Specifier s Guide TJ-8620 January

8 PORTAL FRAME ASSEMBLY Single Portal Use one strap on each side with a minimum uplift capacity of 500 lbs per strap Pre-cut hole for light fixture Pre-cut wiring chase Portal straps 1 2" from edges on both sides of the brace (4 straps total per brace) Beam clear span, 8' to 18'-6" Column base with a minimum uplift capacity of 1,000 lbs Double Portal Portal straps 1 2" from edges on both sides of the brace (4 straps total per brace) Concrete design is the responsibility of the design professional of record Pre-cut hole for light fixture Portal straps 1 2" from edges on both sides of the brace (4 straps total per brace) Beam clear span, 8' to 18'-6" Pre-cut wiring chase Concrete design is the responsibility of the design professional of record PORTAL DESIGN information Using Braces in Portal Frame Assemblies The portal shear braces listed in the Design Loads Portal on Concrete Foundation table on page 9 require the brace-to-header connection detail shown throughout this guide. Increased shear capacity due to the portal acting as a system has been accounted for in the values. When designing portals using braces taller than 931/4" or wider than 18", use the values from the Design Loads Standard Brace on Concrete Foundation table on page 6. To achieve the Attached to Header values shown in the Out-of-Plane Lateral Loads tables on pages 6 and 9, braces must be attached to the header using the supplied screws and Portal Kit straps. Any alternative connections designed by a professional of record should consider shear, header overturning, and lateral out-of-plane capacities. For Portal Installation Details, see page 14. For drilling and trimming information, see pages 12 and 14. Portal Header Design Header width must be 3 1 8" minimum and 5 1 2" maximum. Header depth must be 91 4" minimum and 18" maximum. Induced Forces A portal frame under lateral loads causes the portal header to experience internal stresses in addition to those created by the primary loads (like gravity and wind). These additional stresses are called induced forces and must be considered when designing portal headers. For headers with typical residential uniform loads, the induced moment and shear forces from a portal frame system do not control the design. This is due to the 160% duration of load (DOL) factor used in design and the location of the induced stresses. See ICC ES ESR-2652 for more information. 8 ilevel Brace Specifier s Guide TJ-8620 January 2009

9 ALLOWABLE DESIGN LOADS PORTAL FRAME Design Loads (1) Portal on Concrete Foundation Double Single Portal Brace (2) Assembly (1) Interpolation of design values is allowed for custom height braces. For braces less than 78" tall, use the values for a 78" tall brace. (2) 12" wide braces, 1051/4" tall and less, and all 18" wide braces are allowed in prescriptive applications. (3) Holdown Uplift at is based on an assumed moment-arm equal to the brace width minus 2". Width Height Total Vertical Load per Brace Design Loads table is based on: 160% load duration. No further increases for duration of load are permitted. isb height of 741/2" to 931/4". ASTM A449 or ASTM A193-B7 threaded rod for anchorage; 1" diameter for 24" wide braces, 7 8" for all others. See page 16 for other options. Portal header clear spans of 8' (minimum) to 18'-6" (maximum). and Drift at are for the entire portal assembly. Portal frame assemblies are not for use on RFKs. For shimming and furring requirements, see details on page 14. Portal braces may be used in 2x4 or 2x6 wall framing. Seismic Design Drift at (in.) Holdown Uplift at (3) Wind Design Drift at (in.) Holdown Uplift at (3) isb 12x7 12" 78" 8,000 2, ,520 3, ,370 isb 12x7.5 12" 851/2" 8,000 2, ,620 2, ,480 isb 12x8 12" 931/4" 8,000 2, ,620 2, ,480 isb 18x7 18" 78" 8,000 5, ,285 6, ,515 isb 18x7.5 18" 851/2" 8,000 5, ,925 5, ,220 isb 18x8 18" 931/4" 8,000 5, ,510 5, ,860 isb 12x7 12" 78" 8,000 1, ,115 1, ,925 isb 12x7.5 12" 851/2" 8,000 1, ,220 1, ,040 isb 12x8 12" 931/4" 8,000 1, ,210 1, ,030 isb 18x7 18" 78" 8,000 2, ,285 3, ,515 isb 18x7.5 18" 851/2" 8,000 2, ,625 2, ,890 isb 18x8 18" 931/4" 8,000 2, ,855 2, ,140 Loads Vertical Loads Front View Vertical Loads Out-of-Plane Lateral Loads (1)(2)(3) (PSF) Attached to Header Brace Portal Brace Height Width 7' 7.5' 8' 12" " (1) Based on 160% load duration. No further increases for duration of load are permitted. (2) Table values based on using ilevel Portal Kit to resist header overturning. (3) Load reduction factors: 16" deep headers = " deep headers = 0.78 Out-of-Plane Lateral Loads (psf) Out-of-Plane Lateral Loads table is based on: Braces used in a portal application installed according to the details in this guide. Wall deflection of L/240. Header depth of 14" in a portal system application. Out-of-plane lateral loads consider the total vertical load. Side View ilevel Brace Specifier s Guide TJ-8620 January

10 allowable design loads STACKED SHEAR BRACES Design Loads (1) for Standard Brace in 2nd Floor, Stacked Application Brace Width Height Total Vertical Load Seismic Design (2) Drift at (in.) (2) Wind Design Drift at (in.) isb 18x8 18" " 2,000 1, , isb 18x9 18" " 2,000 1, , isb 18x10 18" " 2,000 1, , isb 24x8 24" " 2,000 1, , isb 24x9 24" " 2,000 1, , isb 24x10 24" " 2,000 1, , (1) Based on 160% load duration. No further increases for duration of load are permitted. (2) Interpolation of design values is allowed for custom height braces. Minimum brace height of 931/4" required. Design Loads (1) for STK Brace in 1st Floor, Stacked Application STK Brace Width Height Total Vertical Load (2) Seismic Design Wind Design (3) isb 18x8-STK 18" " 4,000 2,215 2,435 isb 18x9-STK 18" " 4,000 1,905 2,090 isb 18x10-STK 18" " 4,000 1,725 1,895 isb 18x11-STK 18" " 4,000 1,530 1,685 isb 18x12-STK 18" " 4,000 1,340 1,475 isb 24x8-STK 24" " 4,000 4,435 4,880 isb 24x9-STK 24" " 4,000 3,905 4,295 isb 24x10-STK 24" " 4,000 3,325 3,660 isb 24x11-STK 24" " 4,000 3,010 3,315 isb 24x12-STK 24" " 4,000 2,695 2,965 (1) Based on 160% load duration. No further increases for duration of load are permitted. (2) Maximum axial load = second floor axial load (2,000 lbs) + first floor axial load (4,000 lbs) = 6,000 lbs. (3) Interpolation of design values is allowed for custom height braces. Minimum brace height of 931/4" required. First floor braces in stacked applications may NOT be trimmed. V 2 h 3 V 1 h 2 h 1 V base Reactions at Footing for Stacked Brace Applications Brace Width 18" 24" Design Category Maximum Total Uplift Maximum Base Overturning Moment (in.-lbs) Wind 23, ,640 Seismic 19, ,640 Wind 23, ,880 Seismic 21, ,900 The maximum reactions for footings shown on this page are based on A449 threaded rod and the information on page 16. Other footing details may change the allowable design loads and therefore require analysis by a design professional. Stacked shear braces may not be used with a raised floor kit. Instead, use an ilevel Brace on the first floor that will extend the height of the wall and floor system. See detail SB9 on page 13. Maximum joist depth between stacked braces is 16". STK-designated braces are required on the first floor of stacked-brace applications. The second floor brace must match the width of the first floor brace. See page 15 for installation details. capacities shown are for individual braces only. To resist forces at both upper and lower floors in a two-story application, check the shear at each floor against the maximum capacity for EACH brace. Check the overturning moment (OM) against the maximum capacity for the system. See page 11 for an example. OM = (V 2 h 2 ) + (V 1 h 1 ) Drift Equation for Lower Braces Δ = h 2 1 (3V 1 h 3 + 2V base h 1 ) K Δ...deflection at the top of the lower brace (in.) h 1...lower brace height (in.) h 3...upper brace height (in.) V 1...applied shear load on lower brace V 2...applied shear load on upper brace V base V 1 + V 2 K x 10 9 for 18" wide braces 36.7 x 10 9 for 24" wide braces 10 ilevel Brace Specifier s Guide TJ-8620 January 2009

11 overturning forces Designing for Overturning Forces Vertical Load When specifying stacked shear brace applications, it is important to consider overturning forces. Analysis should be performed by following these steps: 1. Analyze the structure to determine the shear forces at each floor. Figure 1 illustrates the forces developed in a stacked shear brace. V 2 V 2 = 600 lbs 2. Select an ilevel Brace for each floor, and verify that the shear capacity of the brace meets or exceeds what is required. See below for more information. 3. Calculate the system s overturning moment and shear. 4. Compare the required forces to the ilevel Brace capacity. h 2 isb 18x8 Brace Calculating the Overturning Resistance of a Stacked Brace The maximum overturning resistance provided by an ilevel Brace depends on the footing capacity, the anchor bolt capacity, and the brace capacity. For all ilevel Braces, the footing capacity controls. Concrete-footing uplift capacities are based on the footing width, the anchor bolt embedment depth, and the loading condition. See pages 10 and 16. V base shear at footing V 1...shear at the top of the first floor brace V 1 h 1 V 1 = 1,200 lbs isb 18x9 STK Brace V 2...shear at the top of the second floor brace h 1...height to top of the first floor brace h 2...height to top of the second floor brace w...width of brace OM...base overturning moment U...uplift (tension in brace anchorage) C...compression (compression in brace anchorage) V base = OM U Figure 1 Elevation of stacked braces, and the structural forces developed during lateral events. C V base = 1,800 lbs U 16,003 Design Example h 2 V 2 = 600 lbs isb 18x8 Brace V 1 = 1,200 lbs isb 18x9 STK Brace h 1 = " h 2 = " Given Uncracked concrete SDC B; Wind Speed = 100 mph (wind controls) First story wall height = 9'; shear brace choice = isb 18x9 STK Second story wall height = 8'; shear brace choice = isb 18x8 Upper brace shear, V 2 = 600 lbs Lower brace shear, V 1 = 1,200 lbs at footing, V base = 1,800 lbs Floor joist depth = 14", and the total floor depth = 14" + ¾" + 2 (11/2") = 17¾" Solution 1 From the Reactions at Footing for Stacked Brace Applications table on page 10, the maximum base overturning moment (OM max ) is: 368,640 in.-lb. 3 Calculate the required overturning moment (OM) using the shear at each story and the story heights: OM = (V 2 h 2 ) + (V 1 h 1 ) OM = (600 x ) + (1,200 x ) = 256,050 in.-lb. 4 Compare the allowed maximum base overturning moment (from step 1) to the required overturning moment. If the capacity is exceeded, consider adding an additional brace to the first story. 368,640 in.-lb > 256,050 in.-lb required. OK. The stacked isb 18x9-STK and isb 18x8 are adequate to resist the overturning and shear forces in this example. Verify the footing requirements for the stacked shear braces. From page 16, a 28" footing that has a C 3 of 14" and an of 10" is required. V base = 1,800 lbs U C 16,003 lbs OM = 256,050 in.-lb 2 Compare the shear at each brace to the maximum allowable shear for each brace shown in the tables on page 10. Second floor brace: shear for an isb 18x8 = 1,420 lbs > 600 lbs required. OK. First floor brace: shear for an isb 18x9 STK = 2,090 lbs > 1,800 lbs (1, lbs) required. OK. ilevel Brace Specifier s Guide TJ-8620 January

12 INSTALLATION DETAILS, trim zones, and allowable holes Standard ilevel Brace Installation Small Holes Two top plates or as specified Optional OSB shim, 7 8" maximum No holes allowed in top 8" For trim zones, see below Verify brace is plumb OPTION A 6¾" lag screws, provided: 6 with 12" brace (3 front, 3 back) 8 with 18" brace (4 front, 4 back) 12 with 24" brace (6 front, 6 back) Start screws 31 2" (±1 2") from bottom of double top plate or header 31 2" (±1 2") Optional OSB shim, 7 8" max. Do not install screws in electrical chase from either side Countersink (1 4" deep x 1" dia.) and install at an angle that prevents screws from exiting sides of top plates or header. Offset screws 1 2" front to back to avoid interference. An installation template is available from your ilevel representative. EDGE DRILL ZONE Middle 1 3 of brace thickness HOLES Maximum three holes in face and three in edge ¾" diameter holes, maximum 6" o.c. minimum FACE DRILL ZONE Maintain 11 2" min. edge distance from chase and outside edge, typical No holes allowed in lower 40" of brace SB1 Hardened nut Washer Anchor bolt spacer OPTION B 6¾" lag screws, provided, installed from the top: 6 with 12" brace 8 with 18" brace 12 with 24" brace Optional OSB shim, 7 8" maximum Do not install screws in electrical chase For trim zones, see below Install nut finger-tight plus 1 /8 turn, min. Holdown Threaded rod Ensure concrete is level and smooth beneath brace. Grind and fill as necessary. Foundation system design is the responsibility of the design professional of record Optional OSB shim, 7 8" maximum SB2 Large Holes for Standard and STK isbs (in addition to allowed small holes above) HOLES 4 5 8" diameter holes, maximum Maximum two 4 5 8" holes or one 41/4" x 12" hole No minimum on center spacing required No holes allowed in top 8" FACE DRILL ZONE Center of brace face as shown Minimum 12" above existing hole Trim Zones Trim height from the top of the brace only. Do not trim the sides or bottom. DO NOT trim the bottom brace in a stacked brace application. 31 2" maximum allowable trim for portal braces. 12" and 18" standard braces taller than 931/4" may be trimmed down to a minimum height of 741/2". 24" braces may be trimmed down to a minimum height of 89¾". SB11 12 ilevel Brace Specifier s Guide TJ-8620 January 2009

13 RAISED FLOOR DETAILS RFK Installation RFK Interior View Raised Floor Kit ❶ Thread the ported coupler nuts and threaded rods onto anchor bolts ❷ Lower block onto threaded rods and swing bottom of block and spacer plates into place ❸ Install ilevel Brace on block Top shear-transfer plate (pre-attached) Attach USP MP4F framing anchor with 0.148" x 11/2" nails. Fill all nail holes. 31 2" TimberStrand LSL RFK block (face grooved side to exterior of building) Bottom shear-transfer plate (pre-attached) 7 8" diameter threaded rod 7 8" ported coupler nut Steel shim 11/4" TimberStrand LSL or ilevel 1 1 /8" rim board SB8 RFK block Not applicable for 24" shear braces Ledger In-line Brace Notch floor sheathing around brace Joist hanger Foundation system design is the responsibility of the design professional of record TJI joist Sill plate Sill plate anchor bolt (per code) ilevel Brace sized to include the floor system height and installed directly on the foundation 11/2" Foundation system design is the responsibility of the design professional of record 11/4" TimberStrand LSL or ilevel 1 1 /8" rim board TJI joist Sill plate 11/2" minimum clearance required on each side of the anchor bolt spacer to accommodate the RFK Ledger Joist hanger Sill plate anchor bolt (per code) SB7 Not applicable for 24" shear braces SB9 Foundation system design is the responsibility of the design professional of record DO NOT modify the Raised Floor Kit. For floor assemblies of non-standard heights (such as floor sheathing thicker than ¾", sill plates thicker than 11 2", or floor joists different than standard TJI joist depths), adjust the total assembly height with steel shims or by trimming at the top of the ilevel Brace. Place the Raised Floor Kit directly on the concrete. DO NOT place on top of the sill plate. Attach floor joists to the RFK block using approved joist hangers. Alternatively, joists may rest on the remaining sill plate if adequate bearing is available. Notch floor sheathing around RFK block and ilevel Brace. Support the floor sheathing with a ledger attached directly to the block or ilevel Brace (depending on elevation requirements) to accommodate vertical loads and lateral load transfer. Use connections equivalent to the floor sheathing nailing schedule. The ilevel Brace must sit directly on the RFK top shear-transfer plate. Using compressible materials such as sheathing or wood shims in this area will affect the performance of the assembly. ilevel Brace Specifier s Guide TJ-8620 January

14 PORTAL INSTALLATION DETAILS Portal Frame Brace Portal Frame Column 31 2" wide x 91 4" 18" deep header as specified. See SB5 for other header widths and allowable furring. Portal straps (provided): Maintain 1/2" minimum edge distance. Attach with sixteen 0.148" x 2 3 8" minimum nails, 8 into header and 8 into Brace 6¾" lag screws, provided: Optional OSB shim, 7 8" maximum 6 with 12" brace (3 front, 3 back) 8 with 18" brace (4 front, 4 back) 12 with 24" brace (6 front, 6 back) Do not install screws in electrical chase from either side Header as specified. For 51 4" or 51 2" header, use furring as required. See detail SB5 below. Use a strap on each side with a minimum uplift capacity of 500 lbs per strap Verify brace is plumb SB3 Hardened nut Washer 31 2" (±1 2") Install nut finger-tight plus 1 /8 turn, min. Holdown Threaded rod Ensure concrete is level and smooth beneath brace. Grind and fill as necessary. Anchor bolt spacer Start screws 31 2" (±1 2") from bottom of double top plate or header Optional OSB shim, 7 8" max. Foundation system design is the responsibility of the design professional of record Countersink (1 4" deep x 1" dia.) and install at an angle that prevents screws from exiting sides of top plates or header. Offset screws 1 2" front to back to avoid interference. An installation template is available from your ilevel representative. SB4 TimberStrand LSL portal column or solid sawn column (3" x 31/2" minimum) per the design professional of record (trim as required) Column base with a minimum uplift capacity of 1,000 lbs Foundation system design is the responsibility of the design professional of record Portal Trim Zone Trim height from the top of the brace only. Do not trim the sides or bottom. 31 2" maximum allowable trim for portal braces. Portal Frame Brace with 51 4" or 51 2" Wide Header (Similar for 3 1 8" header) 91 4" 18" deep header as specified. Center over brace width. Minimum 21 2" x 10" furring of 7 8" thick OSB. Attach furring to brace with ten 0.131" x 21/2" nails. With 3 1 8" wide headers, attach furring to header. SB5 Portal straps (provided): Maintain 1/2" minimum edge distance. Attach with sixteen 0.148" x 2 3 8" min. nails, 8 into header and 8 into Brace Connect header to brace with 6 3 4" lag screws (provided): 6 with 12" brace (3 front, 3 back) 8 with 18" brace (4 front, 4 back) 12 with 24" brace (6 front, 6 back) 14 ilevel Brace Specifier s Guide TJ-8620 January 2009

15 MULTISTORY KIT Installation DETAILS Stackable Brace Assembly ❺ Install nut, then 3" x 3" washer so that the top of washer is flush with the top of flooring ➏ Place brace over threaded rod. Install round washer and nut finger-tight plus ¹ 8 turn, minimum. ➍ Hand tighten rod until 1¾" 2¾" remains above the sheathing ❸ Cut 31/2" x 31/2" notches in flooring. Notching rim board on the inside may be required to accommodate rods. ➐ Install 2 layers of full-depth-andwidth, solid blocking under entire width of brace. See Rimboard Detail below. Nail with 0.148" x 3" nails. Use: Three nails per ply on narrow section Three rows of four nails each in center section ❷ 7 8" diameter threaded rod (1" dia. with 24" brace). Drill holes through double top plate for rods. Make holes ¹ 8" larger than threaded rod. 14" or 20" ❶ Place holdowns on the lower shear brace. Verify that bolt-hole centers are 14" apart for 18" braces or 20" apart for 24" braces. Nail using the provided nails. Lower brace must be an STK-designated, stackable brace SB 10 Not applicable for 12" shear braces Outside View of Connection ➑ Install T-plate with 0.148" x 11/2" nails. Fill all nail holes " max. floor sheathing thickness Welded nut pre-installed on multistory holdowns DO NOT trim lower shear brace in a stacked brace application. Maximum allowable shim is 7 8" thick and must be installed between the holdown brackets and the double top plate. Notching rim may be required for threaded rod, depending on rim thickness Rimboard Detail Locate splice as required Notching rim may be required for nut, depending on floor thickness ➒ Use three USP MP4F framing anchors. Fill all holes with 0.148" x 11/2" nails. Threaded Threaded Use rim as rod diameter rod blocking + 1 8" Blocking under entire width of brace ilevel Brace Specifier s Guide TJ-8620 January

16 anchorage embedment depths for Anchorage No increases for duration of load are permitted. Appropriate for use in areas governed by IBC or IRC. No special inspection per IBC or is required. is measured from the top of the washer to the top of the footing. Anchorage embedment is based on ACI 318 Appendix D. Concrete assumptions: Minimum f' c of 2,500 psi; Φ = 0.85 (condition A). For additional information, see ICC ES ESR-2652 and ilevel Brace Technical Bulletin (Reorder #TB-912). Concrete Embedment Depths and Footing Dimensions for Threaded Rod (1)(2)(3) Uncracked Concrete Cracked Concrete Application Standard or Portal Braces Two-story or Stacked Braces Standard or Portal Braces Two-story or Stacked Braces Brace Embedment Depth Minimum Footing Dimensions Anchor Bolt Minimum Diameter Footing Width Wind Seismic (SCD C-E) C 1 C 2 C 3 isb 12x_ 7 8" 16" 6" 7" 6" 10" 10" isb 18x_ 7 8" 16" 10" N.A. 6" 10" 10" 7 8" 22" 7" 8" 9" 13" 10" isb 24x_ 1" 25" 9" N.A. 11" 14" 12" 1" 28" 9" 10" 12" 16" 14" isb 18x_ STK 7 8" 28" 10" 10" 12" 16" 14" isb 24x_ STK 1" 25" 10" N.A. 11" 14" 12" 1" 30" 9" 11" 13" 17" 13" isb 12x_ 7 8" 22" 7" 8" 9" 13" 12" isb 18x_ 7 8" 28" 9" 9" 12" 16" 12" isb 24x_ 1" 32" 10" 11" 14" 18" 16" isb 18x_ STK 7 8" 36" 10" 13" 16" 20" 18" isb 24x_ STK 1" 35" 10" 12" 16" 19" 16" (1) Anchor bolts are ASTM A449 or ASTM A193 B7 threaded rod and are applicable for all braces and applications within this guide. (2) ASTM A307 threaded rod may be substituted in all 12" wide brace applications. (3) ASTM A307 threaded rod may be substituted for braces where the holdown uplift at allowable design shear is less than shown in the following table: Anchor Bolt Diameter Wind Seismic (SCD C-E) 7 8" 15,200 lbs 11,400 lbs 1" 19,900 lbs 14,900 lbs C 3 is measured from the end of the template. A Stem wall length " min. C 2 Total threaded rod assembly length 2 1 8" Concrete wall height 1 3 4" (min.) Stem wall per code Foundation systems are the responsibility of the design professional of record. C 3 C 3 Anchor bolt spacer A alternate anchorage for 12" shear braces Footing C 1 C 1 C 2 Footing width per code Section A A Alternate Anchorage For 12" ilevel Braces 16 Anchor Manufacturer Embedment Depth, Anchor Bolt Spacer Required STB28 USP " Yes SSTB28 Simpson " Yes SSTB34 Simpson " Yes Check with manufacturer for capacities and installation instructions. Exception: Leave 2 1 8" of anchor bolt above the anchor bolt spacer. Not for use with masonry walls. Minimum concrete f' c of 2,500 psi. Place jam nut on anchor bolt 2 1 8" from the top of the bolt. Stem wall 8" x 18" min. 5" min. Anchor bolt Footing design spacer B by others Top View of B Concrete Stem wall 8" x 18" min. Wall and Footing 5" min. Anchor bolt Footing design ilevel Brace Specifier s spacer B Guide TJ-8620 January by others 2009 B 2 1 8" 2 1 8" 1 3 4" (min.) #4 rebar Stem wall per code 1 3 4" (min.) #4 rebar #4 rebar Stem wall per code Footing width per code Section View of Concrete #4 rebar Wall and Footing Section B B

17 ANCHOR BOLT INSTALLATION Anchor Bolt Installation On the bottom end of each rod create a double nut and washer assembly by installing a washer between two hex nuts, leaving two threads showing at the bottom. On the top end of each rod, install a jam nut roughly 21/4" from the top. Set the anchor bolt spacer on the jam nuts. Slide the ilevel anchor bolt holder over the threads, flush with the end of the threaded rod, and snap it shut (invert the anchor bolt holder depending on concrete form layout). Hand-tighten the jam nut to the underside of the anchor bolt spacer " Grooves Grooves Vertical faces Nail the ilevel anchor bolt assembly to the form edge using three nails (alignment depends on header thickness). To better secure the assembly during concrete placement, tie the threaded rods to footing reinforcement " Threaded Rod Assembly Anchor Bolt Holder Attachment for 4x_ Header Attachment to Center isb Under 6x_ Header Groove Vertical face To install shear brace flush to the outside face of wall, align bolt holder s vertical faces with inside face of formwork To install shear brace centered under 5 1 2" header or beam, align bolt holder s grooves with inside face of formwork 1 3 4" 2 3 4" ilevel anchor bolt spacer ilevel anchor bolt holder Total threaded rod assembly length = 3 3 8" + + concrete wall height Threaded rod Tie threaded rod to footing reinforcement (recommended) Double nut and washer assembly ilevel Brace Specifier s Guide TJ-8620 January

18 Anchorage details Portal Anchorage at Garage Curb 2" (min.) A Anchor bolt spacer 2 1 8" Stem wall per code 1 3 4" min. Jam nut below anchor bolt spacer Concrete wall height per code or plan (not part of ), top of footing to top of washer 1 4" top of washer to bottom of rod 3" min. coverage For C 1, C 2, C 3, and, see tables on page 16. C 3 is measured from the end of the template. 6" curb height, typ. Concrete wall height per 6" curb height, typ. code or plan (not part of ) 7 8" dia. (1" dia. with 24" isb) threaded rod,, top of footing grade A449 or A193 B7 to top of washer 3" min. coverage #4 rebar per code or plan C 3 Brace width C 3 Double nut and C 1 C 2 A washer assembly Footing width Section A A Foundation systems are the responsibility of the design professional of record. Concrete Foundation Slab on Grade 2" min. Concrete wall height per code or plan (not part of ), top of footing to top of washer 1 4" top of washer to bottom of rod 3" min. coverage B C 3 Brace width C 3 B Anchor bolt spacer 2 1 8" 7 8" dia. (1" dia. with 24" isb) threaded rod, grade A449 or A193 B7 #4 rebar per code or plan Double nut and washer assembly Concrete wall height per code or plan (not part of ), top of footing to top of washer 1 3 4" min. C 1 C 2 Footing width Section B B Jam nut below anchor bolt spacer For C 1, C 2, C 3, and, see tables on page 16. C 3 is measured from the end of the template. Foundation systems are the responsibility of the design professional of record. 18 ilevel Brace Specifier s Guide TJ-8620 January 2009

19 ANCHORAGE DETAILS Concrete Foundation with Stem Wall or Basement 2 1 8" Concrete wall height per code or plan (not part of ), top of footing to top of washer 1 4" top of washer to bottom of rod 3" min. coverage For C 1, C 2, C 3, and, see tables on page 16. For a two-stage pour, a second anchor bolt spacer is recommended. See detail. C 3 is measured from the end of the template. 2" min " min. C C 3 Brace width C 3 C Anchor bolt spacer 7 8" dia. (1" with 24" isb) threaded rod, grade A449 or A193 B7 Ported coupler, compatible with A193 B7 threaded rod, as required Monolithic or two-stage pour Second anchor bolt spacer recommended for two-stage pour #4 rebar per code or plan Double nut and washer assembly Concrete wall height per code or plan (not part of ), top of footing to top of washer C 1 C 2 Footing width Section C C Jam nut below anchor bolt spacer Stem wall per code Jam nut below anchor bolt spacer Foundation systems are the responsibility of the design professional of record " 2" min. CMU wall height per code or plan (not part of ) Concrete Masonry Wall for Prescriptive Use Only (12" and 18" Braces Only) D Solid grouted wall section the width of the brace plus 2", min. both sides. Use 3,500 psi grout, min. l e 2" min. Flat anchor bolt spacer 1 2" dia. x 5" long bolt, see details above 7 8" dia. threaded rod, grade A449 or A193 B7 Flat Anchor-Bolt-Spacer Bolt Locations 12" isb 18" isb " 5" 5" (Use existing holes) (Use existing holes) CMU wall height per code or plan (not part of l ) 1 2" min. grout clearance Jam nut below flat anchor bolt spacer 8" min. CMU wall with 3,500 psi min. solid grout, top of footing to top of washer 1 4" top of washer to bottom of rod 3" min. coverage For C 1, C 2, C 3, and, see tables on page 16. Ported coupler, compatible with A193 B7 threaded rod, as required Anchor bolt spacer recommended, top of footing to top of washer #4 rebar per code or plan Double nut and washer assembly C 3 Brace width C 3 C 1 C 2 D Footing width Section D D Jam nut below anchor bolt spacer For anchorage into CMU walls, the grout strength must be 3,500 psi, minimum. Two anchor bolt spacers are recommended: Order flat anchor bolt spacer for CMU wall anchorage. Use standard anchor bolt spacer for concrete footing. Notch bottom of shear brace (1/4" x 1" x 1") to accommodate carriage bolts. Foundation systems are the responsibility of the design professional of record. C 3 is measured from the end of the template. ilevel Brace Specifier s Guide TJ-8620 January

20 WALL BRACING What is Wall Bracing? Wall bracing resists lateral (sideways) movement in a structure, and consists of a system of specially constructed wall segments tied to the roof and floor. Prescriptive wall bracing requirements are commonly satisfied in one of four ways: 1. Construct 4'-wide wall sections of code-prescribed materials. 2. Construct narrow wall sections (at least 28" wide) of OSB (oriented strand board) or plywood and include tiedowns. 3. Use prefabricated wall sections designed to resist lateral loads. 4. Construct alternate site-built or prefabricated portal frame. The most common panel materials used for wall bracing are 4' x 8' structural panels (OSB or plywood) or gypsum board. However, ilevel Braces are strong enough that any width of brace may replace any 4'-wide, site-built panel. Refer to section IRC R for specifics on braced wall requirements and construction methods. Criteria for Prescriptive Design The following conditions must be met in order to use prescriptive methods: Wind speeds of less than 110 mph or less than 100 mph in hurricane regions. Seismic design category (SDC) of A through D 2. Additional restrictions apply based on loads and building geometry. See ilevel s Conventional Construction Guide (Reorder #1502) or contact your local building official. Some jurisdictions require an engineered design for all homes. Check with the local building official to determine if a house plan requires an engineered design or can be prescriptively specified. Local wind speed and seismic categories can be obtained from your local building official. Most ilevel Braces can be counted as 4' of bracing and are a 1-for-1 substitution for site-built shear wall sections. Exception: 12" wide braces greater than 105¼" tall How to PRESCRIPTIVELY Specify Braced Panels Procedure 1. Define the wall line to be braced. All portions of the wall line must be within 4' of the braced wall line. See page Calculate how many panels are required to meet the 25' o.c. spacing requirement by dividing the wall length by 25'. Always round up. If more than one braced wall panel is required, place the first two panels at, or near, each end of the wall line. Then place any additional braced wall panels in the remaining wall length as evenly spaced as possible. When a wall section does not provide sufficient length for a 4' braced wall panel, try an ilevel Brace instead. 3. Adjust the panel locations at both ends of the wall line, if required. For exterior wall lines in SDC A C, the distance from the end of the wall to the nearest edge of a braced wall panel cannot be more than 12'-6". For exterior wall lines in SDC D 0 D 2, panels must be placed at the ends of the wall line. Refer to IRC R for exceptions. Note: An ilevel Brace may be located up to 8' from the end of the braced wall line in SDC D 0 D Check the percentage of bracing provided. To do this, add together the widths of all braced wall panels specified in step 2 (an ilevel Brace counts as 4' of bracing regardless of its actual width). Divide the total panel width by the wall length; then multiply by 100. If the resulting percentage is less than that required by IRC Table R , add additional bracing until the result meets or exceeds the requirement. 5. If a wall line cannot meet the bracing requirements following this procedure, additional analysis may be required, or the wall line may need to be modified. Contact your ilevel representative for assistance. 20 ilevel Brace Specifier s Guide TJ-8620 January 2009

21 PRESCRIPTIVE BRACING REQUIREMENTS Laying Out Braced Wall Lines and Panels in a Typical House Braced wall panels must occur at least every 25' of the braced-wall line length 55' 1 Site-built panels must be at least 4' long 19' Braced wall panels may be offset no more than 4' from a braced wall line 3' 2 21' Wall or opening Code-accepted braced wall panel Identifies each braced wall line for easier tracking Braced panel must start within 12'-6" of the end of a braced wall line (8'-0" for SDC D) 4' 28' Braced wall lines may be A spaced up to 35' apart B C 3 Braced wall lines, typical PRESCRIPTIVE BRACE EXAMPLE Given First story of a two story house. Total exterior wall length = 41'-10". Determine the required bracing for the wall line shown: Legend Opening in wall Wall Brace locations 4' site-built panel 3' 3' 6' 9' 7'-4" 10' 2' 4' 1'-6" 2' 41'-10" Situation I Seismic Design Category: A Wind Speed: 100 mph 1 No portion of the braced wall line may be offset more than 4'. The offset is 3', which meets the requirements. So the braced wall line is the total wall length of 41'-10". 2 A braced wall panel is required every 25' of wall length. Find the number of panels required. 41'-10" 25' = 1.7. Rounding up, at least two panels are required. 3 Place the panels to meet the 25' spacing and the 12'-6" end distance requirements. Place one 4' site-built panel in the 9' long wall section. Position the panel on the left side of the 9' section in order to meet the end distance requirement of 12'-6" or less. There are no 4' long wall sections available on the right side of the wall line for a site-built panel, so place one 12" isb at the offset in the right side of the wall section. Verify that the panels meet the 25' spacing and the 12'-6" end distance requirements: The distance between panel centers is 19'-4" 19'-4" < 25' OK The end distance for the site-built panel is 8' 8' < 12'-6" OK The end distance for the isb is 12' 12' < 12'-6" OK 4 For SDC A, IRC Table R requires that at least 16% of the wall line length be braced. Find the percentage of bracing provided by adding the panel widths together and dividing by the wall length. Then multiply by 100. Remember: An isb is equivalent to 4' of bracing regardless of its actual width. 4' + 4' = 8' (8' 41'-10") x 100 = 19% 19% > 16% OK The braced panel layout is complete. 6' 9' 7'-4" 10' 2' 4' 1'-6" 2' 41'-10" Situation II Seismic Design Category: D o Wind Speed: 90 mph 1, 2, and 3 same as Situation I. 4 However, for SDC D 0, the panels must be at the ends of exterior wall lines. In order to meet that requirement and the 25' spacing rule, braced panels will have to be added rather than simply moved to the ends of the wall line. Therefore, add a panel at the left and right ends of the wall. Since there isn t space for 4' panels, use two 12" isbs. There are now four panels, and the distance between panel centers remains less than 25'. 5 For SDC D 0, IRC Table R requires that at least 45% of the wall line length be braced. Following the same procedure as Step 4 in Situation 1: 4' + 4' + 4' + 4' = 16' (16' 41'-10") x 100 = 38% 38% < 45% NOT OK! 6 Determine how much additional bracing is needed. Multiply the percentage required by the wall length: 0.45 x 41'-10" = 19'. 19' minus the existing 16' equals 3' of additional bracing needed. One more panel will be sufficient. 7 There are two options: A) Add a second 4' braced panel in the 9' wall section. B) Add a 4' braced panel in the 4' space near the offset. While both options meet IRC provisions, choose option B and add a braced panel near the offset. The braced panel layout is complete. ilevel Brace Specifier s Guide TJ-8620 January

22 PORTALS One Double Portal Two Single Portals 8'-0" min. 18'-6" max. 8'-0" min. 18'-6" max. 8'-0" min. 18'-6" max. Quantity Size Panels 2 isb 12x7, 7.5, or 8 Headers 1 See table below 24'-0" max. Quantity Size Panels 2 isb 12x7, 7.5, or 8 Columns 2 31/2" x 31/2" x brace height Headers 2 See table below One Single and One Double Portal Three Single Portals 8'-0" min. 18'-6" max. 8'-0" min. 18'-6" max. 8'-0" min. 18'-6" max. 8'-0" min. 18'-6" max. 8'-0" min. 18'-6" max. Quantity Size Panels 3 isb 12x7, 7.5, or 8 Columns 1 31/2" x 31/2" x brace height Headers 2 See table below Header must be single span. Do not run headers continuous over more than one portal. To transfer shear across header joints in prescriptive applications, use one LSTA 24 strap, minimum, (placed across the top for 91/2" deep headers) unless the header is attached to a continuous double top plate. 24'-0" max. Quantity Size Panels 3 isb 12x7, 7.5, or 8 Columns 3 31/2" x 31/2" x brace height Headers 3 See table below A minimum of 1,000 lbs of uplift capacity is required at the top and bottom of a single, portal column. PORTAL HEADER SIZING TABLE How to Use This Table 1. Determine appropriate Roof Load and House Width. 2. Locate Rough Opening. 3. Select header size and material. Minimum Header Size Required Non-Snow Area 125% Snow Area 115% Roof Load (PSF) 20LL + 15DL 20LL + 20DL 25LL + 15DL 30LL + 15DL 40LL + 15DL House Rough Opening Width 9'-3" 16'-3" 18'-3" 24' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 14" T M P 30' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 14" M P 36' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 16" T M P 24' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 14" M P 30' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 16" T M P 36' 31/2" x 91/4" T M P 31/2" x 14" M P 31/2" x 16" M P 24' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 14" M P 30' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 16" T M P 36' 31/2" x 91/4" T M P 31/2" x 14" M P 31/2" x 16" M P 24' 31/2" x 91/4" T M P 31/2" x 14" T M P 31/2" x 14" M P 30' 31/2" x 91/4" T M P 31/2" x 14" M P 31/2" x 16" M P 36' 31/2" x 91/4" T M P 31/2" x 16" T M P 5 1/4" x 14" M P 24' 31/2" x 91/4" T M P 31/2" x 14" M P 31/2" x 16" M P 30' 31/2" x 91/4" T M P 31/2" x 16" M P 51/4" x 14" M P 36' 31/2" x 91/4" M P 51/4" x 14" M P 51/4" x 16" T M P Rough opening House width T 1.55E TimberStrand LSL M 1.9E Microllam LVL P 2.0E Parallam PSL 22 ilevel Brace Specifier s Guide TJ-8620 January 2009

23 PRESCRIPTIVE ANCHORAGE Prescriptive Embedment Depths and Footing Dimensions Application Standard or Portal Brace Stacked Brace Loading Condition Embedment Length (1), (in.) Minimum Footing Width Minimum C 1 Minimum C 2 Minimum C 3 Wind, SDC A B 6" 16" 6" 10" 10" SDC C E See Concrete Embedment Depths table on page 16 Wind 10" 28" 12" 16" 12" SDC A B 10" 28" 12" 16" 10" SDC C E 10" 28" 12" 16" 14" (1) Measured from the top of the footing to the top of the washer. Minimum concrete f' c of 2,500 psi " (min.) Standard holdown anchors are 7 8" ASTM A449 or ASTM A193-B7 threaded rod. For 12" braces, A307-grade threaded rod may be used with the embedment lengths shown. For 18" braces, A307-grade threaded rod may be used with the embedment lengths shown, if the brace is used in an SDC A or B application (SDC for detached houses) and in a non-stacked application. A Stem wall length " min. C 2 C 1 Total threaded rod assembly length 2 1 8" Concrete wall height Stem wall per code C 3 is measured from the end of the template. Threaded Rod Installation To ensure the proper on-center spacing of threaded rods or anchor bolts, use an anchor bolt spacer on a 7 8" jam nut. See details on page 17. C 3 C 3 Anchor bolt spacer A Footing C 1 C 2 Footing width per code Section A A alternate anchorage for 12" shear braces Alternate Anchorage For 12" ilevel Braces Anchor Manufacturer Embedment Depth, Anchor Bolt Spacer Required STB28 USP " Yes SSTB28 Simpson " Yes Check with manufacturer for capacities and installation instructions. Exception: Leave 2 1 8" of anchor bolt above the anchor bolt spacer. Not for use with masonry walls. Minimum concrete f' c of 2,500 psi. Place jam nut on anchor bolt 2 1 8" from the top of the bolt. Anchor bolt spacer Anchor bolt spacer B B B B 5" min. 5" min. Top View of Concrete Wall and Footing Stem wall 8" Stem x 18" wall min. 8" x 18" min. Footing design by Footing othersdesign by others 2 1 8" 2 1 8" 1 3 4" (min.) 1 3 4" (min.) #4 rebar #4 rebar Stem wall per Stem code wall per code #4 rebar #4 rebar Footing width Footing per code width per code Section View of Concrete Wall and Footing Section B B ilevel Brace Specifier s Guide TJ-8620 January

24 WALL SOLUTIONS WE CAN HELP YOU BUILD SMARTER. At ilevel, our goal is to help you build solid and durable homes by providing high-quality residential building products and unparalleled technical and field support. Floors and Roofs: Start with the best framing components in the industry: our ilevel Trus Joist Silent Floor joists; TimberStrand LSL rim board; and TimberStrand LSL, Microllam LVL, and Parallam PSL, headers and beams. Pull them all together with our durable ilevel roof sheathing and self-gapping Edge or Edge Gold floor panels. Walls: Get the best value out of your framing package use TimberStrand LSL studs for tall walls, kitchens, and bathrooms, and our traditional, solid-sawn lumber everywhere else. Cut down installation time by using TimberStrand LSL headers for doors and windows, and our ilevel wall sheathing with its handy two-way nail lines. Software Solutions: If you are a design professional or lumber dealer, ilevel offers a full array of software packages to help you specify individual framing members, create cut lists, manage inventories even help you design whole-house framing solutions. Contact your ilevel representative to find out how to get the software you need. Technical Support: Need technical help? ilevel has one of the largest networks of engineers and sales representatives in the business. Call us for help, and a skilled member from our team of experts will contact you within one business day to evaluate and help solve your structural frame problems GUARANTEED. CONTACT US OUR GUARANTEE iLevel8 ( ) ilevel@weyerhaeuser.com 2910 East Amity Road Boise, ID P.O. Box 8449 Boise, ID January 2009 Reorder TJ-8620 This document supersedes all previous versions. If this is more than one year old, contact your dealer or ilevel rep. NW Weyerhaeuser, ilevel, Microllam, Parallam, Silent Floor, Structurwood, Structurwood Edge, Structurwood Edge Gold, TimberStrand, and Trus Joist are registered trademarks of Weyerhaeuser by Weyerhaeuser Company. All rights reserved. Printed in the USA.