THE CONCEPT OF LIGHT GAUGE STEEL CONSTRUCTION Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Light Gauge Steel Framing Members THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Light Gauge Steel Framing Members Steel components are cold-rolled from steel sheet. Cold-forming increases metal strength. Members are essentially noncombustible equivalents of wood light frame construction. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Used as vertical studs, and horizontal joists, rafters, and headers THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION C-Studs and Joists Used as vertical studs, and horizontal joists, rafters, and headers Standards sizes Depth 1-5/8 to 12 in. Width 1-1/4 to 2-1/2 in. Metal thickness 18 to 97 mils (0.018 to 0.097 in.) Example designation: 600S162-54 600: 6.00 inches deep S: Stud or joist 162: 1.625 (1-5/8) inches wide 54: 54 mils (.054 inches) metal thickness Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Example designation: 600T125-33 THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Tracks Used at top and bottom of wall framing and at ends of floor framing, to hold studs or joists Analogous to wall plates and rim joists in light wood frame construction Standard sizes Depth to match studs or joists Width 1-1/4 to 2 in. Example designation: 600T125-33 6.00 inches deep Track 1.25 in. wide 33 mils metal thickness Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Used for bridging, blocking, and other reinforcing and bracing THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Channels Used for bridging, blocking, and other reinforcing and bracing Also called cold-formed channels Standard sizes Depth ¾ to 2-1/2 in. Width ½ in. Example designation: 075U50-54 0.75 in. deep U-channel 0.50 inches wide 54 mils metal thickness Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Used for bridging, backing, furring Also called hat channels THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Furring Used for bridging, backing, furring Also called hat channels Standard sizes Depth 7/8 or 1-1/2 in. Width 1¼ in. at raised surface, 2½ in. at base Example designation: 087F125-30 0.875 in. deep Furring channel 1.25 inches wide at raised surface 30 mils metal thickness Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Example designation: 2-800L150-43 THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION L-Headers Used for simplified header construction over openings in loadbearing walls Break-formed angles (sheet metal bent in fabricator's shop to the specified size) Standard sizes Long leg 6 to 10 in. Short leg 1½ in. Example designation: 2-800L150-43 2 (doubled) angles required 8.00 in. long leg length L-Header 1.5 in. short leg length 43 mils metal thickness Section View Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Framing Accessories Various sheet metal clips, stiffeners, bracing, and hangers are used to make connections and reinforce framing. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Special Products Many manufacturers offer proprietary members that offer various performance advantages or efficiencies. Example right: The heavy dimpling or extra corrugation result in framing members that are stiffer than their conventional counterparts of the same metal thickness. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Slip track: A top track with extra deep legs and slotted holes THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Special Products Slip track: A top track with extra deep legs and slotted holes Allows fastening of nonloadbearing studs to track while permitting deflection in the track Studs are intentionally cut short so that a deflection gap remains. Deflection in the slab above does not impart unintended loads into the wall framing. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Special Products A jamb-stud, a single, deeper framing member designed to replace two conventional studs at either side of a framed rough opening Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Contemporary ASTM standards specify metal thickness in decimal inches. THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Sheet Metal Thickness Thicker members are stronger and stiffer, but also heavier and more expensive. Thickness is traditionally expressed as metal gauge (or gage), with lower numbers corresponding to thicker metal. Translation of gauge numbers to metal thickness is not always consistent. Contemporary ASTM standards specify metal thickness in decimal inches. Minimum thickness of steel sheet Gauge Loadbearing framing Nonloadbearing framing 12 0.097 in. (2.46 mm) 14 0.068 in. (1.73 mm) 16 0.054 in. (1.37 mm) 18 0.043 in. (1.09 mm) 20 0.033 in. (0.84 mm) 0.030 in. (0.75 mm) 22 0.027 in. (0.69 mm) 25 0.018 in. (0.45 mm) Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Cutting Light Gauge Sheet Metal THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Cutting Light Gauge Sheet Metal Tin snips (aviator's snips): quiet, clean, slower than power methods Power shears Power saw with abrasive or carbide-toothed blade Torch cutting Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Fastening Light Gauge Sheet Metal THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Fastening Light Gauge Sheet Metal Self-drilling, self-tapping screws are most common. (top) Crimping tools mutually deform parts to be joined. (middle) Nail-like pins are power-driven. (bottom) Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Fastening Light Gauge Sheet Metal THE CONCEPT OF LIGHT Gauge STEEL CONSTRUCTION Fastening Light Gauge Sheet Metal Welded joints can achieve higher strengths but are more labor intensive to make than mechanically fastened joints. Welding is best suited to thicker sheets that are less susceptible to melt-through (burn through) than thinner sheets. Top: Plug welds Middle: Slot welds Bottom: Flare vee weld Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

FRAMING PROCEDURES 12 LIGHT GAUGE STEEL CONSTRUCTION Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Framing methods parallel wood light frame platform construction. FRAMING PROCEDURES Framing Framing methods parallel wood light frame platform construction. Steel joists spaced from 12 to 24 in. o.c. are framed into tracks or channels. Web stiffeners or reinforcing are inserted where concentrated loads might cause joist webs to buckle. Construction panels are fastened with mastic adhesive and screws. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

FRAMING PROCEDURES Framing Heavier beam equivalents, such as the ridge beam in the top illustration, can be constructed by nesting standard joists. Simple angles or end clips facilitate joining of perpendicular members. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

FRAMING PROCEDURES Framing Joist hangers, gusset plates, and folded track ends are other connection methods. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Window header connection to supporting studs FRAMING PROCEDURES Framing Window header connection to supporting studs Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

FRAMING PROCEDURES Bracing Slender steel members require bracing at regularly spaced intervals to reduce the tendency to buckle. Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Specifying Light Gauge Steel Framing LIGHT GAUGE STEEL CONSTRUCTION Specifying Light Gauge Steel Framing Division 5 Metals, Section 05 40 00—Cold-Formed Metal Framing Structural, loadbearing framing Exterior wall framing (subject to wind loads) Division 9 Finishes Section 09 22 16—Non-Structural Metal Framing Interior nonloadbearing framing Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.

Light Gauge Steel Compared to Light Wood Framing Advantages LIGHT GAUGE STEEL CONSTRUCTION Light Gauge Steel Compared to Light Wood Framing Advantages Like wood light framing: versatile, flexible, simple to construct Noncombustible and immune to insect attack Dimensionally stable, with consistent material properties Lighter weight Disadvantages Members require more frequent bracing Readily conducts heat and requires extra attention to eliminating thermal bridging effects Susceptible to corrosion Fundamentals of Building Construction, Materials & Methods, 5th Edition Copyright © 2009 J. Iano. All rights reserved.