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HomeMy WebLinkAbout06176.pdf BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 1 SECTION 06176 - METAL-PLATE-CONNECTED WOOD TRUSSES PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. 1.2 SUMMARY A. Section Includes: 1. Wood roof trusses. 2. Wood girder trusses. 3. Wood truss bracing. 4. Metal truss accessories. B. Related Requirements: 1. Division 2 Section "Termite Control" for site application of borate treatment to wood trusses. 2. Division 6 Section "Sheathing" for roof sheathing and subflooring. C. Allowances: Provide wood truss bracing under the Metal-Plate-Connected Truss Bracing Allowance as specified in Division 1 Section "Allowances." 1.3 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. 1.4 ACTION SUBMITTALS A. Product Data: For fire-retardant-treated lumber, metal-plate connectors, metal truss accessories, and fasteners. 1. Include data for wood-preservative treatment from chemical treatment manufacturer and certification by treating plant that treated materials comply with requirements. Indicate type of preservative used and net amount of preservative retained. 2. Include data for fire-retardant treatment from chemical treatment manufacturer and certification by treating plant that treated materials comply with requirements. Include physical properties of treated materials based on testing by a qualified independent testing agency. 3. For fire-retardant treatments, include physical properties of treated lumber both before and after exposure to elevated temperatures, based on testing by a qualified independent testing agency according to ASTM D 5664. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 2 4. For products receiving a waterborne treatment, include statement that moisture content of treated materials was reduced to levels specified before shipment to truss fabricator. 5. Include copies of warranties from chemical treatment manufacturers for each type of treatment. B. 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. 7. Contractor to design truss temporary and permanent bracing and submit sealed drawings to engineer of record for review. C. 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. 1.5 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. 1.6 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 that complies with quality-control procedures in TPI 1 and that involves third-party inspection by an independent testing and inspecting agency acceptable to Architect and authorities having jurisdiction. 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. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 3 1.7 DELIVERY, STORAGE, AND HANDLING A. Handle and store trusses to comply with recommendations in TPI BCSI, "Building Component Safety Information: Guide to Good Practice for Handling, Installing, Restraining, & Bracing Metal Plate Connected Wood Trusses." 1. Store trusses flat, off of 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. PART 2 - PRODUCTS 2.1 PERFORMANCE REQUIREMENTS A. Delegated Design: Engage a qualified professional engineer, as defined in Division 1 Section "Quality Requirements," to design metal-plate-connected wood trusses. B. Structural Performance: Provide metal-plate-connected wood trusses 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 of 1/360 of span. C. Comply with applicable requirements and recommendations of the following publications: 1. TPI 1, "National Design Standard for Metal Plate Connected Wood Truss Construction." 2. TPI DSB, "Recommended Design Specification for Temporary Bracing of Metal Plate Connected Wood Trusses." 3. TPI BCSI, "Building Component Safety Information: Guide to Good Practice for Handling, Installing, Restraining, & Bracing Metal Plate Connected Wood Trusses." 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 grading agencies indicated. If no grading agency is indicated, provide lumber that complies with the applicable rules of any rules writing agency certified by the 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 19 percent maximum moisture content at time of dressing. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 4 B. Minimum Chord Size for Roof Trusses: 2 by 6 inches nominal (38 by 140 mm actual) for both top and bottom chords. C. Minimum Specific Gravity for Top Chords: 0.50. D. Permanent Bracing: Provide wood bracing that complies with requirements for miscellaneous lumber in Division 6 Section "Rough Carpentry." 2.3 FIRE-RETARDANT-TREATED WOOD A. General: Where fire-retardant-treated materials are indicated, use materials complying with requirements in this article, that are acceptable to authorities having jurisdiction, and with fire- test-response characteristics specified as determined by testing identical products per test method indicated by a qualified testing agency. B. Fire-Retardant-Treated Lumber by Pressure Process: Products with a flame-spread index of 25 or less when tested according to ASTM E 84, and with no evidence of significant progressive combustion when the test is extended an additional 20 minutes, and with the flame front not extending more than 10.5 feet (3.2 m) beyond the centerline of the burners at any time during the test. 1. Use treatment that does not promote corrosion of metal fasteners. 2. Exterior Type: Treated materials shall comply with requirements specified above for fire- retardant-treated lumber and plywood by pressure process after being subjected to accelerated weathering according to ASTM D 2898. Use for exterior locations and where indicated. 3. Interior Type A: Treated materials shall have a moisture content of 28 percent or less when tested according to ASTM D 3201 at 92 percent relative humidity. Use where exterior type is not indicated. 4. Design Value Adjustment Factors: Treated lumber shall be tested according ASTM D 5664 and design value adjustment factors shall be calculated according to ASTM D 6841. For enclosed roof framing, framing in attic spaces, and where high- temperature fire-retardant treatment is indicated, provide material with adjustment factors of not less than 0.85 modulus of elasticity and 0.75 for extreme fiber in bending for Project's climatological zone. C. Kiln-dry lumber after treatment to a maximum moisture content of 19 percent. D. Identify fire-retardant-treated wood with appropriate classification marking of testing and inspecting agency acceptable to authorities having jurisdiction. E. Application: Treat items indicated on Drawings. 2.4 METAL CONNECTOR PLATES A. Manufacturers: Subject to compliance with requirements, provide products by one of the following: 1. Alpine Engineered Products, Inc.; an ITW company. 2. MiTek Industries, Inc.; a subsidiary of Berkshire Hathaway Inc. 3. Truswal Systems Corporation; an ITW company. B. Source Limitations: Obtain metal connector plates from single manufacturer. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 5 C. General: Fabricate connector plates to comply with TPI 1. D. Hot-Dip Galvanized-Steel Sheet: ASTM A 653/A 653M; 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 (Z180) coating designation; and not less than 0.036 inch (0.9 mm) thick. 1. Use for interior locations unless otherwise indicated. 2. Hot-Dip Heavy-Galvanized-Steel Sheet: ASTM A 653/A 653M; Structural Steel (SS), high- 2.5 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/A 153M of Type 304 stainless steel. B. Nails, Brads, and Staples: ASTM F 1667. 2.6 METAL FRAMING ANCHORS AND ACCESSORIES A. Manufacturers: Subject to compliance with requirements, provide products by one of the following: 1. Simpson Strong-Tie Co., Inc. 2. USP Structural Connectors. B. Basis-of-Design Product: Subject to compliance with requirements, provide product indicated on Drawings or comparable product by one of the following: 1. Simpson Strong-Tie Co., Inc. 2. USP Structural Connectors. C. Allowable Design Loads: Provide products with allowable design loads, as published by manufacturer, that meet 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. D. Galvanized-Steel Sheet: Hot-dip, zinc-coated steel sheet complying with ASTM A 653/A 653M, G60 (Z180) coating designation. 1. Use for interior locations unless otherwise indicated. E. Truss Tie-Downs: Bent strap tie for fastening roof trusses to wall studs below, 1-1/2 inches (38 mm) wide by 0.050 inch (1.3 mm) thick. Tie fastens to one side of truss, top plates, and side of stud below. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 6 F. Roof Truss Clips: Angle clips for bracing bottom chord of roof trusses at non-load-bearing walls, 1-1/4 inches (32 mm) wide by 0.050 inch (1.3 mm) thick. Clip is fastened to truss through slotted holes to allow for truss deflection. G. Roof Truss Bracing/Spacers: U-shaped channels, 1-1/2 inches (38 mm) wide by 1 inch (25 mm) deep by 0.040 inch (1.0 mm) thick, made to fit between two adjacent trusses and accurately space them apart, and with tabs having metal teeth for fastening to trusses. 2.7 MISCELLANEOUS MATERIALS A. Galvanizing Repair Paint: SSPC-Paint 20, with dry film containing a minimum of 94 percent zinc dust by weight. 2.8 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. 2.9 SOURCE QUALITY CONTROL A. Special Inspections: Owner will engage a qualified special inspector to perform special inspections. 1. Provide special inspector with access to fabricator's documentation of detailed fabrication and quality-control procedures that provide a basis for inspection control of the workmanship and the fabricator's ability to conform to approved construction documents and referenced standards. 2. Provide special inspector with access to places where wood trusses are being fabricated to perform inspections. B. Correct deficiencies in Work that special inspections indicate does not comply with the Contract Documents. PART 3 - EXECUTION 3.1 INSTALLATION A. Install wood trusses only after supporting construction is in place and is braced and secured. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 7 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. 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 Division 6 Section "Rough Carpentry." 2. Install and fasten strongback 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 meet 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 with galvanized repair paint according to ASTM A 780 and manufacturer's written instructions. D. Protective Coating: Clean and prepare exposed surfaces of metal connector plates. Brush apply primer, when part of coating system, and one coat of protective coating. BICKFORD OF CARMEL, IN 12/12/2012 METAL-PLATE-CONNECTED WOOD TRUSSES 06176 - 8 1. Apply materials to provide minimum dry film thickness recommended by coating system manufacturer. END OF SECTION 06176