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BCSI 06
For information on: Jobsite storage Truss handling Temporary bracing Fall protection Construction loading
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ContentsB1 – Handling, Installation and
BracingB2 – Installation and BracingB3 – Web Bracing/ReinforcementB4 – Construction LoadingB5 – Damage, Modifications and ErrorsB6 – Gable End Frame BracingB7 – Parallel Chord TrussesB8 – Toe-nailing for UpliftB9 – Multi-Ply TrussesB10 – Post Frame TrussesB11 – Fall Protection
Development of BCSI
Engineers Manufacturers
Manufacturers Suppliers Contractors
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BCSI Booklet Replaces…
HIB-91 Booklet
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BCSI B-Series
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BCSI B-Series Replaces...
HIB-91 Sheet
HIB-98 Poster
WTCA-B1 Warning Poster TTB WTCA-B2
B1 Guide for Handling,Installing & Bracing
Consequences of improper installation may be collapse of the structure
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B1 Summary Sheet
HIB-91 Sheet
WTCA-B1 Warning Poster
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B1 Banding Warning
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B1 Handling
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B1 Handling
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B1 Storage
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B1 Storage
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B1 Hand Erection
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B1 Hoisting
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B1 Hoisting Recommendations
From BCSI Booklet
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B1 Hoisting Recommendations
From BCSI Booklet
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B1 Hoisting Recommendations
From BCSI Booklet
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B1 Bracing Warning
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B1 Ground Bracing
B1 Top Chord BracingSee
TCTLBTable
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B1 Bottom Chord Bracing
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B1 Web Plane Bracing
Lateral brace splicing
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Look for “Truss Brace Splicing Methods” in the November SBC Magazine
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B1 PCT Bracing
(PCT)(PCT)
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B1 Diagonal Bracing
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B1 Truss Installation
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B1 Constructions Loads
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B1 Construction Loads
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B1 Alterations
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B2 Truss Installation & Temporary Bracing
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B2 Scope
From p.8:
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B2 Scope
B2 Doesn’t Cover These3x2 or 4x2 Flat Trusses Trusses spaced > 2 ft. o.c.
From p. 8 From p. 8
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B2 Warnings
B2 Top Chord Bracing
Ground bracing not shown Take special care with spans over 60 ft.
B2 Checklist
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B2 Steps to Setting Trusses
B2 Step 2 - Ground Braces
B2 Step 3 - Set First Truss
B2 Step 4 - Next 4 Trusses
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B2 Step 4 - TCTLB Options
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B2 Note on Bracing Materials
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B2 Step 5 - Top Chord Diagonals
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B2 Step 5 - Top Chord Sheathing
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B2 Step 6 – Web Bracing
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B2 Step 6 – High End Trusses
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B2 Step 7 – Bottom Chord Bracing
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B2 Step 8 – Repeat Groups of 4
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B2 Sheath Early and Often
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B2 Alternate Installation Method
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B2 Special Conditions
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B3 Web Member Permanent Bracing/Web Reinforcement
B3 Compression Web Members
Unstable if unrestrained Check Design Drawing if restraint
req’d
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B3 Bracing vs. Reinforcement
Bracing provides lateral support, reducing buckling length
Reinforcement increases cross-section, making web more stable
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B3 Six Methods of Restraint
These items apply to all six methods:
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B3 CLBs and Diagonals
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B3 CLBs and Diagonals
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B3 CLBs and Diagonals
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B3 T-Reinforcement
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B3 L-Reinforcement
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B3 Scab Reinforcement
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B3 Metal Reinforcement
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B3 Stacked Webs
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B3 Gable End Frame Bracing
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B3 Gable End Frames Designed to
transfer vertical loads
But may also experience lateral loads Sheathing,
bracing and connections must be designed for this transfer
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B3 Load Transfer Path
B3 Poorly Designed System
B3 Design Considerations Gable End Frame
Reinforcement prevents failure of individual vertical webs
Frame to End Wall
Correct connection prevents hinge joint
Bracing, blocking and diaphragm design creates safe load path
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B3 Bracing and Blocking
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B3 Bracing and Blocking
B3 Gable End Reinforcement
Horizontal reinforcement:
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B3 Gable End Reinforcement
Individual L- or T-reinforcements
B3 Gable End Reinforcement
Scab reinforcements
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B3 Building Designer Detail
B3 Building Designer Detail
B3 Avoid Hinge Joint
Balloon Framed End Wall
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B3 Scissor Truss End Wall
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B3 Avoid hinge points in walls!
Additional Note: This wall will not meet the prescriptive method criteria under IRC for a braced wall.
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B4 Construction Loading
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B4 Construction Loads
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B4 Loading DOs and DON’Ts
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B4 Loading DOs and DON’Ts
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B4 Loading DOs and DON’Ts
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B4 Loading DOs and DON’Ts
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B4 Loading DOs and DON’Ts
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B4 Loading DOs and DON’Ts
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B4 Loading DOs and DON’Ts
B4 Loading DOs and DON’Ts
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B5 Truss Damage, Modifications and Installation
Errors
B5 Truss Damages
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B5 Steps for Repair
B5 Repair Techniques
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B5 Report Damage
B5 Truss Repair Detail
B6 Section
B6 used to be on Gable end bracing that information has now moved to section B3.
B6 is intended to be used for additional topics in future additions of BCSI
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B7 Parallel Chord Trusses
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B7 Lumber Orientation
Guidelines for 3x2 or 4x2 only
For 2x_ orientationsee BCSI-B2
B7 PCT Bearing
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B7 Temporary Bracing
100
B7 Stabilize Truss Ends Temporary Bracing or Permanent Blocking
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B7 Correct Placement
102
B7 Truss Tags
B7 Strongback Bridging Helps limit deflection and/or
vibration
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B7 Construction Loads on PCT
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B8 Toe-Nailing for Uplift
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B8 Uplift Forces
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B8 Toe-Nailed Connections Are three toe-nails enough?
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B8 1- Proper Toenail Installation
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B8 2- Top Plate Lumber Grade and
species
110
B8 3- Type of Nails
0.162″ x 3.5″
B8 Is Toe-Nailing Enough? Toe-nail values must exceed expected uplift
For example:A 16d common ina Southern Pinetop plate offers72 pounds ofuplift resistance.
If there are threetoe-nails, the totaluplift resistanceIs 3x72=216 pounds
72
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B8 Load Duration Factors
For wind uplift resistance use the factor of 1.6.Therefore, 216x1.6 = 346 pounds
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B8 Alternatives to Toe-Nailing
Check published uplift capacities of mechanical connectors
114
R802.10.5 Truss to wall connection
Trusses shall be connected to wall plates by the use of approved connectors having a resistance to uplift of not less than 175 pounds (79.45 kg.) and shall be installed in accordance with the manufacturer's specifications. For roof assemblies subject to wind uplift pressures of 20 pounds per square foot (0.958 kN/m2) or greater, as established in Table R301.2(2), adjusted for height and exposure per Table R301.2(3), see section R802.11.
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IRC R802.10.5 The code requirement was added in the IRC
2003 in a perhaps well-intentioned effort to address a perceived issue from the proponent's point of view. Now that it is in the code, it is proving difficult to
remove. A number of code jurisdictions have amended the language
or struck the language out of their code adoption. The 175 lb value is unrelated to any real design parameters
or linked to any truss length. It arbitrarily discriminates against one well respected construction method. No specific evidence was or can be provided to justify this requirement.
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IRC R802.10.5 TPI 1 requires that a Truss Design
Drawing include reaction forces and directions, which would include a value for uplift based upon the structure's design parameters for wind. There is no valid reason for not using this
calculated value in the consideration of the uplift connection requirements.
IRC R802.10.5 Much of the US is in the 90 mph basic wind speed
zone. The resistance for uplift, beyond the prescriptive fastening
requirements of Table R602.3(1) is really seldom an issue, especially for structures categorized as Exposure B and with a Mean Roof Height of less than 30 feet. IRC Table R301.2(2) is used to trigger the need for special
connection requirements per Table R802.11. Only high wind speed areas, highly exposed structures or extremely tall structures ever qualify for the special requirements. When the calculated uplift requires a connection of a specific value, WTCA supports providing resistance in a manner acceptable to the EOR or building code official, not based upon an arbitrary requirement.
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B9 Multi-ply Girders
B9 Girders Designed to carry extra loads Max. 6 plies, fastened together to act as one
4-ply 5-ply
120
B9 Fastener Schedule Specified on
Truss Design Drawing
SAMPLE
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B9 Nail Fasteners Fasteners using nails only are
specified on girders with three plies or less
122
B9 Screw Fasteners Special screws on up to four plies
123
B9 Screw Fasteners Screws on 2-ply 3x or 4x2 floor-type
trusses
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B9 Bolt Fasteners Bolts on 4 to 6 plies In addition, nails may also be required
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B9 Good Installation Practices
Fasten plies together before lifting, if possible
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B10 Post Frame Trusses
HIB-98 Poster
B10 Post Frame Trusses Part of an engineered building system Spaced at 4′ to 12′ o.c. Heels attached to posts fixed in ground or
slab Purlins attached directly to truss top chords
B10 Truss Storage
129
B10 Installation
130
B10 Installation
131
B10 1- Ensure Stable Columns
132
B10 2- Stable Base Unit
133
B10 3- Bracing of Base Unit Top Chord
A professional engineer should design a bracing plan for truss spans over 60’ per BCSI Fig.B2-13
134
B10 3- Bracing of Base Unit Bottom Chord
135
B10 3- Bracing of Base Unit In the Roof Plane
- or -
136
B10 3- Bracing of Base Unit In the Web Plane
137
B11 Fall Protection & Trusses
138
B11 Fall Protection Warning
Trusses alone are notdesigned to supportfall protection anchors
B11 Impact Loads A falling worker could cause the
trusses to collapse in a domino effect
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B11 Safer Options
Option 1: Scaffolding
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B11 Safer Options
Option 1: Roof Peak Anchor
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B11 Safer Options
Option 1: Ground Assembly
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Jobsite Safety Package B1 through B4 Handling Checklist
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Truss Tags
145Questions on BCSI?Questions on BCSI?