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	SECTION 05425
	PRE-ENGINEERED COLD-FORMED STEEL TRUSSES
	** NOTE TO SPECIFIER ** TrusSteel, An ITW Company truss system. This section is based on products made by TrusSteel, An ITW Company, which is located at: 3208 Fisher Court, Arlington, TX 76001. Tel: (888)-565-9181. E-mail: dgoodwin@trussteel.com. Web: www.trussteel.com. TrusSteel, An ITW Company makes a unique, proprietary cold-formed steel chord section that, combined with a dedicated truss design and engineering software package, allows local fabricators to supply high quality, reliable designs with great speed and flexibility. Steel trusses are light in weight and easy to deliver, handle, and install, while providing resistance to the insect damage, deterioration, shrinkage, fire damage, and nail popping that affect wood truss assemblies. .
	PART 1	GENERAL
	1.1	SECTION INCLUDES
		A.	Pre-engineered cold-formed steel trusses.
		B.	Cold-formed steel framing accessories.
	1.2	RELATED SECTIONS
	** NOTE TO SPECIFIER ** Delete any sections below not relevant to this project; add others as required.
		A.	Section 05300 - Metal Decking.
		B.	Section 05400 - Cold Formed Metal Framing.
	1.3	DEFINITIONS
		A.	Truss Component Manufacturer: The maker of the components that will be assembled into trusses by the Truss Fabricator. See MANUFACTURERS for acceptable Truss Component Manufacturer.
	** NOTE TO SPECIFIER ** Delete the last sentence in the following paragraph if acceptable Truss Fabricators are not listed in PART 2.
		B.	Truss Fabricator: The manufacturer who assembles the Truss Component Manufacturer's components into completed trusses. See MANUFACTURERS for acceptable Truss Fabricators.
		C.	Truss Designer: The design professional, individual or organization, having responsibility for the design of the trusses. In this case, the Truss Designer is the Truss Component Manufacturer.
	1.4	REFERENCES
	** NOTE TO SPECIFIER ** Delete references from the list below that are not actually required by the text of the edited section.
		A.	AISI/COS/NASPEC 2001: North American Specification for the Design of Cold-Formed Steel Structural Members; American Iron and Steel Institute; 2001 Edition.
		B.	AISI/COFS/GP-2004: Standard for Cold-Formed Steel Framing - General Provisions; 2004.
		C.	AISI/COFS/TRUSS-2004: Standard for Cold-Formed Steel Framing - Truss Design; 2004.
		D.	AISI/COFS - Practice Guide - CF05-1: Code of Standard Practice for Cold-Formed Steel Structural Framing; 2005.
		E.	ASTM A 370-03a - Standard Test Methods and Definitions for Mechanical Testing of Steel Products; 2003.
		F.	ASTM A 500-03a - Standard Specification for Cold-Formed Welded and Seamless Carbon Steel Structural Tubing in Rounds and Shapes; 2003.
		G.	ASTM A 653-00 - Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process; 2000.
		H.	LGSEA - Field Installation Guide for Cold-Formed Steel Roof Trusses; Light Gauge Steel Engineers Association; October 1999.
		I.	LGSEA Technical Note 551d - Design Guide for Construction Bracing of Cold-Formed Steel Trusses; Light Gauge Steel Engineers Association; February 1997.
		J.	LGSEA Technical Note 551e - Design Guide for Permanent Bracing of Cold-Formed Steel Trusses; Light Gauge Steel Engineers Association; February 1998.
	1.5	SUBMITTALS
		A.	Submit under provisions of Section 01 30 00.
		B.	[ Product Data ]: Truss Component Manufacturer's descriptive literature for each item of cold-formed metal framing and each accessory specified in this section.
		C.	Shop Drawings:Detailed drawings prepared by Truss Fabricator that:
	** NOTE TO SPECIFIER ** Indicate special components and installations not fully detailed in manufacturer's product data sheets.
			1.	Indicate in the layout placement drawings the number, types, location, and spacings of trusses and other framing members.
			2.	Indicate details of truss loading, reactions, uplifts, support locations, material sizes and gauges, permanent truss web bracing, and splices as required for a complete installation.
		D.	Design Data: Results of design analysis, bearing the seal and signature of Truss Designer's engineer.
		E.	Installation Instructions: Truss Component Manufacturer's printed instructions for handling, storage, and installation of each item of cold-formed metal framing and each accessory specified in this section.
	1.6	QUALITY ASSURANCE
		A.	Truss Designer: Provide design of trusses by Truss Component Manufacturer, using design methodologies recommended in AISI and LGSEA references.
			1.	Determine mechanical properties of load bearing components by testing in accordance with ASTM A 370-03a.
			2.	Provide design by professional engineer registered in the State in which project is located.
			3.	Provide Truss Fabricator's shop drawings.
		B.	Pre-Installation Meeting: Meet at job site prior to scheduled beginning of installation to review requirements. Require attendance by representatives of the following:
			1.	Truss Fabricator, if requested by installer.
			2.	Installer of this section.
			3.	Other entities directly affecting, or affected by, construction activities of this section, including but not limited to, the following:
			4.	Installer of truss support framing.
			5.	Installer of mechanical systems.
			6.	Installer of electrical systems.
			7.	Review potential interface conflicts; coordinate layout and support provisions.
	1.7	DELIVERY, STORAGE, AND HANDLING OF STEEL TRUSSES
		A.	Pack, ship, handle, unload, and lift shop products in accordance with Truss Component Manufacturer's recommendations and in manner necessary to prevent damage or distortion.
		B.	Store and protect products in accordance with Truss Component Manufacturer's recommendations and in manner necessary to prevent damage, distortion and moisture buildup.
	PART 2	PRODUCTS
	2.1	MANUFACTURERS
	** NOTE TO SPECIFIER ** Alpine Engineered Products (the Truss Component Manufacturer) produces the truss components, which are then assembled into completed trusses by one of their approved fabricators (the Truss Fabricator).
		A.	Acceptable Truss Component Manufacturer: TrusSteel, An ITW Company; 3208 Fisher Court, Arlington, TX 76001. ASD. Tel: (888)-565-9181. E-mail: dgoodwin@trussteel.com. Web: www.trussteel.com.
	** NOTE TO SPECIFIER ** Delete the following paragraph if it is not necessary to list acceptable truss fabricators. Obtain current list of Approved Truss Fabricators known to have the capability of fabricating products of this section from Alpine. Local TrusSteel fabricators can be located on the TrusSteel Web site.]
		B.	Acceptable Truss Fabricators: Truss components shall be fabricated into completed trusses by one of the following fabricators:
			1.	____________________.
			2.	____________________.
			3.	____________________.
	** NOTE TO SPECIFIER ** Delete one of the following two paragraphs; coordinate with requirements of Division 1 section on product options and substitutions.
		C.	Substitutions: Not permitted.
		D.	Requests for substitutions will be considered in accordance with provisions of Section 01 60 00.
			1.	All substitutions must be approved in writing by the Architect or Engineer-of-Record.
			2.	All applications for substitution must include samples and technical data.
	2.2	COMPONENTS
		A.	Pre-Engineered Cold-Formed Steel Trusses: TrusSteel truss component system by Alpine Engineered Products, Inc., providing a complete horizontal framing system, ready for deck installation, meeting specified requirements.
			1.	Truss Type, Span, and Height: As indicated on drawings.
	** NOTE TO SPECIFIER ** Insert name of local code and deflection requirements.
			2.	Comply with requirements of ______________________ code.
			3.	Deflection Under All Loads: 1/______th of span, maximum.
			4.	Deflection Under Live Loads: 1/______th of span, maximum.
			5.	Shop fabricate in accordance with shop drawings, using jigging systems to ensure consistent component placement and alignment of components, and to maintain specified tolerances; field fabrication is strictly prohibited unless performed by authorized Truss Fabricator using Truss Fabricator's shop assemblers and proper jigging systems.
			6.	Shop fabrication of other cold-formed steel framing components into assemblies prior to erection is permitted; fabricate assemblies in accordance with shop drawings.
			7.	Fasten connections within truss assembly with Truss Component Manufacturer's fasteners only and as shown on the shop drawings; welding and other fasteners are prohibited.
			8.	Fabricate straight, level, and true, without rack, and to following tolerances:
			9.	Trusses up to 30 feet (9 m) long: Maximum 1/2 inch (12 mm) variation from design length.
			10.	Trusses over 30 feet (9 m) long: Maximum 3/4 inch (19 mm) variation from design length.
			11.	Trusses up to 5 feet (1500 mm) high: Maximum 1/4 inch (6 mm) variation from design height.
			12.	Trusses over 5 feet (1500 mm) high: Maximum 1/2 inch (12 mm) variation from design height.
		B.	Chords: Cold-formed from ASTM A 653/A 653M galvanized steel sheet, minimum G60 coating; minimum yield strength of 55,000 psi (380 MPa). Rolled or closed edges required to minimize the danger of cutting during handling. Components without rolled edges are prohibited. Dimensions as indicated on Contract Drawings.
	** NOTE TO SPECIFIER ** Select Chords from the next six paragraphs. Retain only sizes required on the specific project and delete all others.
			1.	Nominal 28 mil (22 GA) members:
				a.	Minimum bare metal thickness: 0.0284 inch (0.72 mm).
				b.	Maximum design thickness: 0.0299 inch (0.76 mm).
			2.	Nominal 33 mil (20 GA) members:
				a.	Minimum bare metal thickness: 0.0329 inch (0.84 mm).
				b.	Maximum design thickness: 0.0346 inch (0.88 mm).
			3.	Nominal 43 mil (18 GA) members:
				a.	Minimum bare metal thickness: 0.0428 inch (1.09 mm).
				b.	Maximum design thickness: 0.0451 inch (1.15 mm).
			4.	Nominal 54 mil (16 GA) members:
				a.	Minimum bare metal thickness: 0.0538 inch (1.37 mm).
				b.	Maximum design thickness: 0.0566 inch (1.44 mm).
			5.	Nominal 68 mil (14 GA) members:
				a.	Minimum bare metal thickness: 0.0677 inch (1.72 mm).
				b.	Maximum design thickness: 0.0713 inch (1.81 mm).
			6.	Nominal 97 mil (12 GA) members:
				a.	Minimum bare metal thickness: 0.0966 inch (2.46 mm).
				b.	Maximum design thickness: 0.1017 inch (2.58 mm).
		C.	Webs: Cold-formed ASTM A 500 steel structural tubing; minimum yield strength of 45,000 psi (310 MPa). Dimensions as indicated on Contract Drawings.
	** NOTE TO SPECIFIER ** Select Webs from the next three paragraphs. Retain only sizes required on the specific project and delete all others.
			1.	Nominal 33 mil (20 GA) members:
				a.	Minimum bare metal thickness: 0.033 inch (0.84 mm).
				b.	Maximum design thickness: 0.035 inch (0.89 mm).
			2.	Nominal 43 mil (18 GA) members:
				a.	Minimum bare metal thickness: 0.047 inch (1.19 mm).
				b.	Maximum design thickness: 0.049 inch (1.24 mm).
			3.	Nominal 54 mil (16 GA) members:
				a.	Minimum bare metal thickness: 0.063 inch (1.6 mm).
				b.	Maximum design thickness: 0.065 inch (1.65 mm).
		D.	Fasteners Used in Fabricating Trusses: Screw fasteners recommended by Truss Component Manufacturer, bearing stamp of Truss Component Manufacturer for ready identification.
	PART 3	EXECUTION
	3.1	EXAMINATION
		A.	Verify that bearing surfaces and substrates are ready to receive steel trusses.
	** NOTE TO SPECIFIER ** The tolerances appropriate for truss bearings surfaces are dependent on required tolerances of subsequent construction; coordinate with other sections and modify as required.
		B.	Verify that truss bearing surfaces are within the following tolerances:
			1.	Variation from Level or Specified Plane: Maximum 1/8 inch in 10 feet (6 mm in 3 m).
			2.	Variation from Specified Position: Maximum 1/4 inch (6 mm).
		C.	Verify that rough-in utilities and chases that will penetrate plane of trusses are in correct locations and do not interfere with truss, bracing, or bridging placement.
		D.	Inspect conditions under which installation is to be performed and submit written notification if such conditions are unacceptable to installer.
			1.	Notify Architect/Engineer-of-Record within 24 hours of inspection.
			2.	Beginning construction activities of this section before unacceptable conditions have been corrected is prohibited.
			3.	Beginning construction activities of this section indicates installer's acceptance of conditions.
	3.2	INSTALLATION
		A.	Install trusses in accordance with Truss Component Manufacturer's instructions and Truss Fabricator's shop drawings. Use correct fasteners.
		B.	Place components at spacing indicated on the shop drawings.
		C.	Install all erection (temporary installation) bracing and permanent bracing and bridging before application of any loads; follow recommendations of LGSEA Field Installation Guide for Cold-Formed Steel Roof Trusses.
		D.	Install erection bracing:
			1.	Provide bracing that holds trusses straight and plumb and in safe condition until decking and permanent truss bracing has been fastened to form a structurally sound framing system.
			2.	All sub-contractors shall employ proper construction procedures to insure adequate distribution of temporary construction loads so that the carrying capacity of any single truss or group of trusses is not exceeded.
		E.	Install permanent bracing and bridging as shown in the Architect/Engineer-of-Record's drawings and notes and as shown in the Truss Fabricator's shop drawings.
		F.	Removal, cutting, or alteration of any truss chord, web or bracing member in the field is prohibited, unless approved in advance in writing by the Architect/Engineer-of-Record and the Truss Designer.
		G.	Repair or replace damaged chords, webs, and complete trusses as directed and approved in writing in advance by the Architect/Engineer-of-Record and the Truss Component Manufacturer.
	** NOTE TO SPECIFIER ** This article is optional. Delete if not required.
	3.3	FIELD QUALITY CONTROL
		A.	Owner will provide inspection service to inspect field connections; see Section 01400.
	END OF SECTION