Cold-formed steel — CFS, light-gauge steel, metal stud framing; the names all describe the same thing — is the fastest-growing structural framing system in American mid-rise construction. As engineers who serve as engineer-of-record and delegated designer on panelized CFS communities, here is the plain-language explanation we give owners, GCs, and developers deciding between framing systems.
What does cold-formed steel mean?
Cold-formed steel is sheet steel shaped into structural members at room temperature. Coils of galvanized sheet steel run through roll-forming machines that bend flat steel into C-shaped studs and joists, U-shaped track, and specialty profiles through a series of rollers — no heat involved. That's the difference from hot-rolled steel (“red iron” I-beams), which is formed at the mill at over 1,600°F.
Counterintuitively, cold-forming makes the steel stronger at the bends: the work-hardening of the forming process raises the yield strength exactly where the profile needs stiffness.
Cold-formed steel framing: studs, track, joists, and trusses
A CFS building is framed much like wood — studs in walls, joists in floors, trusses in roofs — but with engineered steel members:
- Studs — C-shaped members (e.g., 362S162-33, 600S162-43) in load-bearing and non-structural walls
- Track — U-shaped channels at the top and bottom of walls that receive the studs
- Joists — deeper C-shapes framing floors
- Cold-formed steel trusses — shop-built roof trusses from CFS channel sections
- Bridging and bracing — channels through stud punchouts that prevent twisting under load
Member sizes follow an industry designator: a “600S162-43” is a 6-inch deep Stud with 1-5/8″ flanges in 43-mil (18-gauge) steel. Gauge thickness in structural CFS typically runs 33 to 97 mils (20 to 12 gauge), in 33 and 50 ksi grades.
Cold-formed steel vs. red iron (hot-rolled structural steel)
The most common comparison we're asked about. Red iron — hot-rolled wide-flange beams and columns — is mill-formed, heavy, crane-erected, and unbeatable for long clear spans and concentrated loads. CFS is light enough to install by hand, shop-panelized for speed, and ideal for the repetitive wall and floor framing of multifamily, hotel, and mixed-use buildings. They are not competitors so much as teammates: many of our projects put red iron at the podium and long spans with CFS framing everything above.
Cold-formed steel vs. wood
Steel's strength-to-weight ratio far exceeds lumber's, and every member is dimensionally identical — no knots, crowning, shrinkage, or twist. CFS doesn't burn, rot, or feed termites, carries lower insurance costs on many projects, and permits taller buildings than wood framing height limits allow. Wood keeps advantages in material cost and labor familiarity; the honest disadvantages of CFS are thermal bridging (solved with continuous insulation detailing), higher thermal expansion, and the need for specialized engineering — which is where a CFS specialty engineer earns their fee.
Codes and standards: AISI, ASTM, and the design manual
CFS design in the U.S. is governed by AISI S100 (the North American Specification for the Design of Cold-Formed Steel Structural Members), with framing standards in AISI S240, and material requirements under ASTM A1003. The AISI Cold-Formed Steel Design Manual implements these standards — and they are referenced by the IBC, so every sealed CFS package we produce is engineered to them.
Why panelized CFS is winning schedules
Machine-fabrication systems (FRAMECAD, Howick and others) roll, punch and label every member directly from the engineer’s panel files — walls arrive on site as finished panels that crews stand in hours. On Oak Preserve, a 12+ building panelized CFS community in North Carolina, TCE produces per-panel shop files, opening schedules and shear-wall packages for every building, and the fire-rated demising wall evaluations the attached units require.
Frequently asked questions
What does cold-formed steel mean?
Cold-formed steel (CFS) is structural steel shaped at room temperature — sheet steel roll-formed or press-braked into C-studs, tracks, joists, and other profiles — rather than hot-rolled at high temperature like traditional I-beams. The cold-forming process actually increases the steel's yield strength at the bends.
Is cold-formed steel the same as light-gauge steel?
Yes — 'light-gauge steel,' 'cold-formed steel,' 'CFS,' and 'metal stud framing' all describe the same family of thin-sheet steel members, typically 33 to 97 mils (20 to 12 gauge) thick. 'Cold-formed steel' is the term used in the governing design standard, AISI S100.
Is cold-formed steel stronger than wood?
Pound for pound, yes — steel has a far higher strength-to-weight ratio than lumber, with no knots, warping, shrinkage, or variation between members. CFS also doesn't burn, rot, or feed termites, which is why mid-rise multifamily projects that exceed wood-framing height limits turn to CFS.
What are the disadvantages of cold-formed steel?
Honest answer: thermal bridging (steel conducts heat, so exterior walls need insulation detailing), higher thermal expansion than wood, specialized labor and engineering requirements, and susceptibility to corrosion if coatings are damaged in corrosive environments. Good engineering and detailing address all four — which is exactly what a CFS specialty engineer is for.
What is the difference between cold-formed steel and red iron?
'Red iron' is hot-rolled structural steel — heavy I-beams and columns, mill-formed at high temperature, erected by crane and typically bolted or welded. CFS is thin-gauge sheet steel formed cold into lightweight profiles that can be panelized in a shop and installed by hand. Red iron excels at long spans and heavy loads; CFS excels at repetitive wall/floor framing, speed, and panelized construction — many buildings use both.
How is cold-formed steel made?
Coils of sheet steel — hot-dip galvanized for corrosion protection — are fed through roll-forming machines that bend the flat sheet into shape through a series of rollers at room temperature. Machine-fabrication systems like FRAMECAD roll, punch, dimple, and label every member directly from the engineer's panel files.
Planning a CFS project — or need delegated design that keeps your fabrication schedule? See our cold-formed steel practice, delegated design services, or try the free CFS panel estimator.