SECTION COLD-FORMED METAL FRAMING

Transcription

1 SECTION COLD-FORMED METAL FRAMING This performance guide specification is part of an architectural specification and is intended to provide a guideline for product selection and may not be appropriate for needs of specific projects. Use of this specification is voluntary and the user needs to edit the guide specification to fit the needs of a specific project, applicable laws and regulations, end user requirements and safety considerations. This performance guide specification provides no guarantee as to product performance, merchantability, or fitness for a particular purpose. Please read the full disclaimer here. PART 1 - GENERAL 1.1 SUMMARY A. General: Read this Section in conjunction with other related Sections B. Delegated Design 1. Complete the Detailed Design, manufacture, supply, install and warrant the work, complying with the visual intent indicated and specified design and performance requirements. 2. Where no material, product or supplier is specified, propose suitable materials and systems prior to the Contract Award which comply with the visual intent indicated and specified design and performance requirements, and be fully responsible for the Detailed Design of the work. 3. Where a particular material, product or supplier is specified, the material, product or supplier shall be deemed indicative representing the Engineer's Design Intent only. Complete the installation using the specified or other product acceptable to the Engineer, in writing. Be fully responsible for the Detailed Design and performance of the Work. 4. Complete the Detailed Design of all interfaces with adjoining trades prior to commencement of manufacture. 5. Ensure that all interfaces are fully coordinated prior to commencement. C. Section Includes 1. Load-bearing wall framing 1

2 2. Exterior non-load-bearing wall framing 3. Soffit framing D. Related Work Sections and documentation 1. Section Thermal Insulation 2. Section Gypsum Board Assemblies 3. Structural Engineer's specification 4. Estidama Pearl Rating System (PRS) - The Pearl Rating System for Estidama, Building Rating System: Design and Construction document by Abu Dhabi Urban Planning Council (UPC) PART 2 - PRODUCTS 2.1 PRODUCT SELECTION A. Load Bearing Wall Framing 1. Steel Studs: Manufacturer's standard C-shaped steel studs, of web depths indicated, punched, with stiffened flanges, and as follows: b) Flange Width: ***35 mm/ 41mm/ 51mm/ 63mm***. 2. Steel Track: Manufacturer's standard U-shaped steel track, of web depths indicated, unpunched, with straight flanges, and as follows: 2.45mm/ Matching steel studs***. b) Flange Width: ***32 mm***. 3. Steel Box or Back-to-Back Headers: Manufacturer's standard C-shapes used to form header beams, of web depths indicated, unpunched, with stiffened flanges, and as follows: b) Flange Width: ***35 mm/ 41mm/ 51mm/ 63mm***. 4. Steel Single- or Double-L Headers: Manufacturer's standard L-shapes used to form header beams, of web depths indicated, and as follows: 2

3 b) Top Flange Width: ***35 mm/ 41mm/ 51mm/ 63mm***. B. Exterior Non-Load-Bearing Wall Framing 1. Steel Studs: Manufacturer's standard C-shaped steel studs, of web depths indicated, punched, with stiffened flanges, and as follows: b) Flange Width: ***35 mm/ 41mm/ 51mm/ 63mm***. 2. Steel Track: Manufacturer's standard U-shaped steel track, of web depths indicated, unpunched, with unstiffened flanges, and as follows: 2.45mm/ Matching steel studs***. b) Flange Width: ***32 mm***. 3. ***Vertical Deflection Clips:*** Manufacturer's standard ***bypass/ head*** clips, capable of accommodating upward and downward vertical displacement of primary structure through positive mechanical attachment to stud web. 4. ***Single Deflection Track:*** Manufacturer's single, deep-leg, U-shaped steel track; unpunched, with unstiffened flanges, of web depth to contain studs while allowing free vertical movement, with flanges designed to support horizontal loads and transfer them to the primary structure, and as follows: b) Flange Width: ***25mm plus the design gap for one-story structures/ and/ 25mm plus twice the design gap for other applications***. 5. Double Deflection Tracks: Manufacturer's double, deep-leg, U-shaped steel tracks, consisting of nested inner and outer tracks; unpunched, with unstiffened flanges. a) Outer Track: Of web depth to allow free vertical movement of inner track, with flanges designed to support horizontal loads and transfer them to the primary structure, and as follows: 1. Minimum Base-Metal Thickness: ***0.84mm/ 1.09mm/ 1.37mm/ 1.72mm/ 2. Flange Width: ***25mm plus the design gap for one-story structures/ and/ 25mm plus twice the design gap for other applications***. 3

4 b) Inner Track: Of web depth indicated, and as follows: 1. Minimum Base-Metal Thickness: ***0.84mm/ 1.09mm/ 1.37mm/ 1.72mm/ 2. Flange Width: ***Insert dimension equal to sum of outer deflection track flange width plus 25mm = To be confirmed by the Engineer during the next project stage.*** 6. Drift Clips: Manufacturer's standard bypass or head clips, capable of isolating wall stud from upward and downward vertical displacement and lateral drift of primary structure through positive mechanical attachment to stud web and structure. C. ***Soffit Framing*** 1. Exterior Soffit Frame: Manufacturer's standard C-shaped steel sections, of web depths indicated, with stiffened flanges, and as follows: a) Minimum Base-Metal Thickness: To be confirmed by the Engineer during the next project stage. b) Flange Width: ***41mm/ 51 mm/ 63 mm***, minimum. 2.2 PERFORMANCE REQUIREMENTS A. Structural Performance: Provide cold-formed steel framing capable of withstanding design loads within limits and under conditions indicated. 1. Design Loads: As indicated on the Design Drawings. 2. Deflection Limits: Design framing systems to withstand design loads without deflections greater than the following: a) Exterior Load-Bearing Wall Framing: ***Horizontal deflection of the wall height, to be confirmed by the Engineer during the next project stage.*** b) Interior Load-Bearing Wall Framing: ***Horizontal deflection of the wall height under a horizontal load of 239Pa, to be confirmed by the Engineer during the next project stage.*** c) Exterior Non-Load-Bearing Framing: ***Horizontal deflection of the wall height, to be confirmed by the Engineer during the next project stage.*** d) Floor Joist Framing: ***Vertical deflection of for live loads and l/ 240 for total loads of the span, to be confirmed by the Engineer during the next project stage.*** e) Roof Rafter Framing: ***Vertical deflection of the horizontally projected span for live loads, to be confirmed by the Engineer during the next project stage. *** 4

5 f) Ceiling Joist Framing: ***Vertical deflection of the span for live loads and 1/ 240 for total loads of the span, to be confirmed by the Engineer during the next project stage. *** 3. Design framing systems to provide for movement of framing members located outside the insulated building envelope without damage or overstressing, sheathing failure, connection failure, undue strain on fasteners and anchors, or other detrimental effects when subject to a maximum ambient temperature change of 67ÖC. 4. Design framing system to maintain clearances at openings, to allow for construction tolerances, and to accommodate live load deflection of primary building structure as follows: a) Upward and downward movement: To be confirmed by the Engineer during the next project stage. 5. Design exterior non-load-bearing wall framing to accommodate horizontal deflection without regard for contribution of sheathing materials. B. Cold-Formed Steel Framing Design Standards: 1. Floor and Roof Systems: AISI S Wall Studs: AISI S Headers: AISI S Lateral Design: AISI S213. C. AISI Specifications and Standards: Unless more stringent requirements are indicated, comply with AISI S100 and AISI S200. D. ***Fire-Resistance Ratings:*** Comply with ASTM E119; testing by a qualified testing agency. Identify products with appropriate markings of applicable testing agency. 1. Indicate design designations from UL's "Fire Resistance Directory" or from the listings of another qualified testing agency. 2.3 MATERIALS A. Low Toxicity Materials: All building materials shall comply with the low toxicity material requirements as stated in PBRS Credit SM-1 within the UPC's Pearl Building Rating System: Design & Construction document. 1. To meet this PBRS Credit, all building materials must not contain materials or compounds with over 1% of constituent materials with the designated R-phrases listed in the UPC document. Submit confirmation that materials comply with the EU 5

6 Risk Phrases (R-Phrases) Directive 67/ 548/ EEC. Annex III. B. Cold-Formed Steel Framing, General 1. Recycled Content of Steel Products: Postconsumer recycled content plus one-half of preconsumer recycled content not less than ***25***%. 2. Steel Sheet: ASTM A1003/ A 1003M, Structural Grade, Type H, metallic coated, of grade and coating weight as follows: a) Grade: ***ST33H (ST230H) / ST50H (ST340H)/ As required by structural performance***. b) ***Coating: ***G60 (Z180), A60 (ZF180), AZ50 (AZ150), or GF30 (ZGF90). *** c) ***Coating: G90 (Z275) or equivalent. *** 3. Steel Sheet for ***Vertical Deflection/ Drift*** Clips: ASTM A653/ A653M, structural steel, zinc coated, of grade and coating as follows: a) Grade: ***33 (230)/ 50 (340), Class 1/ As required by structural performance***. b) Coating: ***G60 (Z180)/ G90 (Z275) ***. C. Framing Accessories 1. Fabricate steel-framing accessories from steel sheet, ASTM A1003/ A1003M, Structural Grade, Type H, metallic coated, of same grade and coating weight used for framing members. 2. Provide accessories of manufacturer's standard thickness and configuration, unless otherwise indicated, as follows: a) Supplementary framing. b) Bracing, bridging, and solid blocking. c) Web stiffeners. d) Anchor clips. e) End clips. f) Foundation clips. g) Gusset plates. h) Stud kickers and knee braces. i) Joist hangers and end closures. j) Hole reinforcing plates. k) Backer plates. 6

7 D. Anchors, Clips and Fasteners 1. Steel Shapes and Clips: ASTM A36/ A36M, zinc coated by hot-dip process according to ASTM A123/ A123M. 2. Anchor Bolts: ASTM F1554, Grade 36 or Grade 55, threaded carbon-steel hexheaded bolts, threaded carbon-steel headless, hooked bolts or threaded carbonsteel headless bolts, with encased end threaded, and carbon-steel nuts; and flat, hardened-steel washers; zinc coated by hot-dip process according to ASTM A153/ A153M, Class C or mechanically deposition according to ASTM B695, Class ***Expansion Anchors:*** Fabricated from corrosion-resistant materials, with allowable load or strength design capacities calculated according to ICC-ES AC193 and ACI 318 greater than or equal to the design load, as determined by testing per ASTM E488 conducted by a qualified testing agency. 4. ***Power-Actuated Anchors:*** Fastener system of type suitable for application indicated, fabricated from corrosion-resistant materials, with allowable load capacities calculated according to ICC-ES AC70, greater than or equal to the design load, as determined by testing per ASTM E1190 conducted by a qualified testing agency. 5. Mechanical Fasteners: ASTM C1513, corrosion-resistant-coated, self-drilling, selftapping, steel drill screws. a) Head Type: Low-profile head beneath sheathing, manufacturer's standard elsewhere. 6. Welding Electrodes: Comply with AWS standards. E. Miscellaneous Materials 1. Galvanizing Repair Paint: In accordance with ***SSPC-Paint 20 or MIL-P-21035B/ ASTM A780***. 2. ***Cement Grout:*** Portland cement, ASTM C150, Type I; and clean, natural sand, ASTM C404. Mix at ratio of 1 part cement to 2-1/ 2 parts sand, by volume, with minimum water required for placement and hydration. 3. ***Nonmetallic, Nonshrink Grout:*** Premixed, nonmetallic, noncorrosive, nonstaining grout containing selected silica sands, portland cement, shrinkage-compensating agents, and plasticizing and water-reducing agents, complying with ASTM C1107/ C1107M, with fluid consistency and 30-minute working time. 4. Shims: Load bearing, high-density multimonomer plastic, and nonleaching; or of coldformed steel of same grade and coating as framing members supported by shims. 7

8 5. Sealer Gaskets: Closed-cell neoprene foam, 6.4mm thick, selected from manufacturer's standard widths to match width of bottom track or rim track members. 2.4 FABRICATION A. Fabricate cold-formed steel framing and accessories plumb, square, and true to line, and with connections securely fastened, according to referenced AISI's specifications and standards, manufacturer's written instructions, and requirements in this Section. 1. Fabricate framing assemblies using jigs or templates. 2. Cut framing members by sawing or shearing; do not torch cut. 3. Fasten cold-formed steel framing members by welding, screw fastening; clinch fastening, pneumatic pin fastening, or riveting as standard with fabricator. Wire tying of framing members is not permitted. a) Comply with AWS D1.3/ D1.3M requirements and procedures for welding, appearance and quality of welds, and methods used in correcting welding work. b) Locate mechanical fasteners and install according to Shop Drawings, with screw penetrating joined members by no fewer than three exposed screw threads. 4. Fasten other materials to cold-formed steel framing by welding, bolting, pneumatic pin fastening, or screw fastening, according to Shop Drawings. B. Reinforce, stiffen, and brace framing assemblies to withstand handling, delivery, and erection stresses. Lift fabricated assemblies to prevent damage or permanent distortion. C. Fabrication Tolerances: Fabricate assemblies level, plumb, and true to line to a maximum allowable tolerance variation of 1:960 and as follows: 1. Spacing: Space individual framing members no more than ±3mm from plan location. Cumulative error shall not exceed minimum fastening requirements of sheathing or other finishing materials. 2. Squareness: Fabricate each cold-formed steel framing assembly to a maximum outof-square tolerance of 3mm. End of Section 8