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HomeMy WebLinkAbout06 17 53 Shop-Fabricated Wood TrussesTHE KENT 06 17 53 - THE KENT Issue Date 05.09.18 SHOP-FABRICATED WOOD TRUSSES THE KENT SECTION 06 17 53 - SHOP-FABRICATED WOOD TRUSSES PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section. 1.2 SUMMARY A. Section Includes: 1. Wood roof trusses. 2. Wood floor trusses. 3. Wood girder trusses. B. Related Requirements: 1. Section 31 31 16 "Termite Control" for site application of borate treatment to wood trusses. 1.3 ALLOWANCES A. Provide wood truss bracing under the Metal-Plate-Connected Truss Bracing Allowance as specified in Section 01 21 00 "Allowances." 1.4 DEFINITIONS A. Metal-Plate-Connected Wood Trusses: Planar structural units consisting of metal-plate- connected members fabricated from dimension lumber and cut and assembled before delivery to Project site. 1.5 ACTION SUBMITTALS A. Shop Drawings: Show fabrication and installation details for trusses. 1. Show location, pitch, span, camber, configuration, and spacing for each type of truss required. 2. Indicate sizes, stress grades, and species of lumber. 3. Indicate locations of permanent bracing required to prevent buckling of individual truss members due to design loads. 4. Indicate locations, sizes, and materials for permanent bracing required to prevent buckling of individual truss members due to design loads. 5. Indicate type, size, material, finish, design values, orientation, and location of metal connector plates. 6. Show splice details and bearing details. THE KENT 06 17 53 - THE KENT Issue Date 05.09.18 SHOP-FABRICATED WOOD TRUSSES THE KENT B. Delegated-Design Submittal: For metal-plate-connected wood trusses indicated to comply with performance requirements and design criteria, including analysis data signed and sealed by the qualified professional engineer responsible for their preparation. 1.6 INFORMATIONAL SUBMITTALS A. Qualification Data: For metal connector-plate manufacturer and fabricator. B. Material Certificates: For dimension lumber specified to comply with minimum specific gravity. Indicate species and grade selected for each use and specific gravity. C. Product Certificates: For metal-plate-connected wood trusses, signed by officer of truss- fabricating firm. D. Evaluation Reports: For the following, from ICC-ES: 1. Metal-plate connectors. 2. Metal truss accessories. 1.7 QUALITY ASSURANCE A. Metal Connector-Plate Manufacturer Qualifications: A manufacturer that is a member of TPI and that complies with quality-control procedures in TPI 1 for manufacture of connector plates. 1. Manufacturer's responsibilities include providing professional engineering services needed to assume engineering responsibility. 2. Engineering Responsibility: Preparation of Shop Drawings and comprehensive engineering analysis by a qualified professional engineer. B. Fabricator Qualifications: Shop that participates in a recognized quality-assurance program, complies with quality-control procedures in TPI 1, and involves third-party inspection by an independent testing and inspecting agency acceptable to Architect and authorities having jurisdiction and is certified for chain of custody by an FSC-accredited certification body. C. Testing Agency Qualifications: For testing agency providing classification marking for fire- retardant-treated material, an inspection agency acceptable to authorities having jurisdiction that periodically performs inspections to verify that the material bearing the classification marking is representative of the material tested. 1.8 DELIVERY, STORAGE, AND HANDLING A. Handle and store trusses to comply with recommendations in SBCA BCSI, "Building Component Safety Information: Guide to Good Practice for Handling, Installing, Restraining, & Bracing Metal Plate Connected Wood Trusses." 1. Store trusses flat, off the ground, and adequately supported to prevent lateral bending. 2. Protect trusses from weather by covering with waterproof sheeting, securely anchored. 3. Provide for air circulation around stacks and under coverings. B. Inspect trusses showing discoloration, corrosion, or other evidence of deterioration. Discard and replace trusses that are damaged or defective. THE KENT 06 17 53 - THE KENT Issue Date 05.09.18 SHOP-FABRICATED WOOD TRUSSES THE KENT PART 2 - PRODUCTS 2.1 PERFORMANCE REQUIREMENTS A. Delegated Design: Engage a qualified professional engineer, as defined in Section 01 40 00 "Quality Requirements," to design metal-plate-connected wood trusses. B. Structural Performance: Metal-plate-connected wood trusses shall be capable of withstanding design loads within limits and under conditions indicated. Comply with requirements in TPI 1 unless more stringent requirements are specified below. 1. Design Loads: As indicated. 2. Maximum Deflection under Design Loads: a. Roof Trusses: Vertical deflection: 1) Total Load: L/240 of span. 2) Live Load: L/360 of span. b. Floor Trusses: Vertical deflection: 1) Total Load: L/360 of span. 2) Live Load: L/480 of span. C. Comply with applicable requirements and recommendations of TPI 1, TPI DSB, and SBCA BCSI. D. Wood Structural Design Standard: Comply with applicable requirements in AF&PA's "National Design Specifications for Wood Construction" and its "Supplement." 2.2 DIMENSION LUMBER A. Lumber: DOC PS 20 and applicable rules of any rules-writing agency certified by the American Lumber Standard Committee (ALSC) Board of Review. Provide lumber graded by an agency certified by the ALSC Board of Review to inspect and grade lumber under the rules indicated. 1. Factory mark each piece of lumber with grade stamp of grading agency. 2. For exposed lumber indicated to receive a stained or natural finish, omit grade stamp and provide certificates of grade compliance issued by grading agency. 3. Provide dressed lumber, S4S. 4. Provide dry lumber with 15 percent maximum moisture content at time of dressing. B. Minimum Specific Gravity for Top Chords: 0.50. C. Permanent Bracing: Provide wood bracing that complies with requirements for miscellaneous lumber in Section 06 10 00 "Rough Carpentry." 2.3 METAL CONNECTOR PLATES A. Basis of Design Product: Subject to compliance with requirements, provide Alpine Engineered Products, Inc.; a division of ITW Building Components Group, Inc.; or a comparable product by one of the following: 1. MiTek Industries, Inc. B. General: Fabricate connector plates to comply with TPI 1. THE KENT 06 17 53 - THE KENT Issue Date 05.09.18 SHOP-FABRICATED WOOD TRUSSES THE KENT C. Hot-Dip Galvanized-Steel Sheet: ASTM A 653; Structural Steel (SS), high-strength low-alloy steel Type A (HSLAS Type A), or high-strength low-alloy steel Type B (HSLAS Type B); G60 coating designation; and not less than 0.036 inch thick. 1. Use for interior locations unless otherwise indicated. 2.4 FASTENERS A. General: Provide fasteners of size and type indicated that comply with requirements specified in this article for material and manufacture. 1. Provide fasteners for use with metal framing anchors that comply with written recommendations of metal framing manufacturer. 2. Where trusses are exposed to weather, in ground contact, made from pressure- preservative treated wood, or in area of high relative humidity, provide fasteners with hot- dip zinc coating complying with ASTM A 153. B. Nails: ASTM F 1667. 2.5 METAL FRAMING ANCHORS AND ACCESSORIES A. Basis of Design Product: Subject to compliance with requirements, provide Simpson Strong-Tie Co.Inc.; or a comparable product by the following: 1. USP Structural Connectors. B. Allowable design loads, as published by manufacturer, shall comply with or exceed those of basis-of-design products. Manufacturer's published values shall be determined from empirical data or by rational engineering analysis and demonstrated by comprehensive testing performed by a qualified independent testing agency. Framing anchors shall be punched for fasteners adequate to withstand same loads as framing anchors. C. Galvanized-Steel Sheet: Hot-dip, zinc-coated steel sheet complying with ASTM A 653, G60 coating designation. 1. Use for interior locations unless otherwise indicated. D. Truss Tie-Downs: Bent strap tie for fastening roof trusses to wall studs below, 2-1/4 inches wide by 0.062 inch thick. Tie fits over top of truss and fastens to both sides of truss, top plates and one side of stud below. E. Girder Truss Tie-Downs: Bent strap tie for fastening roof girder trusses to wall studs below. Tie fits over top of truss and fastens to both sides of truss and top plates. 1. Simpson Strong-Tie: H16-2, unless otherwise indicated on drawings. 2. Provide additional tie-downs if girder truss is wider than 3 inches. F. Roof Truss Clips: Angle clips for bracing bottom chord of roof trusses at non-load-bearing walls, 1-1/4 inches wide by 0.050 inch thick. Clip is fastened to truss through slotted holes to allow for truss deflection. G. Floor Truss Hangers: U-shaped hangers, full depth of floor truss, with 1-3/4-inch- long seat; formed from metal strap 0.062-inch-thick with tabs bent to extend over and be fastened to supporting member. THE KENT 06 17 53 - THE KENT Issue Date 05.09.18 SHOP-FABRICATED WOOD TRUSSES THE KENT H. Roof Truss Bracing/Spacers: U-shaped channels, 1-1/2 inches wide by 1 inch deep by 0.040- inch-thick, made to fit between two adjacent trusses and accurately space them apart, and with tabs having metal teeth for fastening to trusses. I. Drag Strut Connectors: Angle clip with one leg extended for fastening to the side of girder truss. 1. Angle clip is 3 by 3 by 0.239 by 10-1/2 inches with extended leg 10-1/2 inches long. Connector has painted finish. 2.6 MISCELLANEOUS MATERIALS A. Galvanizing Repair Paint: SSPC-Paint 20, with dry film containing a minimum of 92 percent zinc dust by weight. 2.7 FABRICATION A. Cut truss members to accurate lengths, angles, and sizes to produce close-fitting joints. B. Fabricate metal connector plates to sizes, configurations, thicknesses, and anchorage details required to withstand design loads for types of joint designs indicated. C. Assemble truss members in design configuration indicated; use jigs or other means to ensure uniformity and accuracy of assembly, with joints closely fitted to comply with tolerances in TPI 1. Position members to produce design camber indicated. 1. Fabricate wood trusses within manufacturing tolerances in TPI 1. D. Connect truss members by metal connector plates located and securely embedded simultaneously in both sides of wood members by air or hydraulic press. PART 3 - EXECUTION 3.1 INSTALLATION A. Install wood trusses only after supporting construction is in place and is braced and secured. B. If trusses are delivered to Project site in more than one piece, assemble trusses before installing. C. Hoist trusses in place by lifting equipment suited to sizes and types of trusses required, exercising care not to damage truss members or joints by out-of-plane bending or other causes. D. Install and brace trusses according to TPI recommendations and as indicated. E. Install trusses plumb, square, and true to line and securely fasten to supporting construction. F. Space trusses as indicated; adjust and align trusses in location before permanently fastening. G. Anchor trusses securely at bearing points; use metal truss tie-downs or floor truss hangers as applicable. Install fasteners through each fastener hole in metal framing anchors according to manufacturer's fastening schedules and written instructions. THE KENT 06 17 53 - THE KENT Issue Date 05.09.18 SHOP-FABRICATED WOOD TRUSSES THE KENT H. Securely connect each truss ply required for forming built-up girder trusses. 1. Anchor trusses to girder trusses as indicated. I. Install and fasten permanent bracing during truss erection and before construction loads are applied. Anchor ends of permanent bracing where terminating at walls or beams. 1. Install bracing to comply with Section 06 10 00 "Rough Carpentry." 2. Install and fasten strong back bracing vertically against vertical web of parallel-chord floor trusses at centers indicated. J. Install wood trusses within installation tolerances in TPI 1. K. Do not alter trusses in field. Do not cut, drill, notch, or remove truss members. L. Replace wood trusses that are damaged or do not comply with requirements. 1. Damaged trusses may be repaired according to truss repair details signed and sealed by the qualified professional engineer responsible for truss design, when approved by Architect. 3.2 REPAIRS AND PROTECTION A. Protect wood that has been treated with inorganic boron (SBX) from weather. If, despite protection, inorganic boron-treated wood becomes wet, apply EPA-registered borate treatment. Apply borate solution by spraying to comply with EPA-registered label. B. Protect wood trusses from weather. If, despite protection, wood trusses become wet, apply EPA-registered borate treatment. Apply borate solution by spraying to comply with EPA- registered label. C. Repair damaged galvanized coatings on exposed surfaces according to ASTM A 780 and manufacturer's written instructions. 3.3 FIELD QUALITY CONTROL A. Special Inspections: Owner will engage a qualified special inspector to perform special inspections to verify that temporary installation restraint/bracing and the permanent individual truss member restraint/bracing are installed in accordance with the approved truss submittal package. END OF SECTION 06 17 53