Light gauge steel
Light Gauge Steel Framing
Light gauge steel framing — cold-formed steel, CFS, or light steel framing depending on who you ask — is the structural system behind every ifHaus building. This page sets out how the system works, which standards govern it in North America, and where it genuinely differs from wood framing and from the container conversions it gets grouped with.
What it is
Light gauge steel framing uses cold-formed galvanized steel sheet, roll-formed into structural profiles — studs, tracks, joists and trusses — rather than hot-rolled steel sections or dimensional lumber. "Cold-formed" means the profile is shaped at room temperature, which is what allows thin sheet to carry load efficiently.
The result is a framing system with the geometry of a wood-framed house and the material behaviour of steel: dimensionally stable, non-combustible, immune to rot and insects, and precise enough that a factory can hold tolerances a site crew cannot.
It is not the same thing as a heavy steel structure. Heavy steel uses hot-rolled beams and columns and belongs to larger spans and multi-storey commercial work. Light gauge steel is a load-bearing panel system, and low-rise housing is exactly where it is strongest.
How a project is specified
Every one of these is a project variable, not a catalogue number. That is the point of an engineered system — the frame is sized for the site, not sold from a shelf.
| Profile geometry and thickness | Sized by structural calculation from the span, storey count and load case |
|---|---|
| Galvanized coating class | Selected for the corrosion exposure of the location; this is what sets the service life of the frame |
| Stud spacing | Follows from the load path and the sheathing system, not a fixed default |
| Wind and snow loads | Taken from the design values that apply at the site |
| Seismic design category | Determined by the site, and it drives the bracing and shear wall layout |
| Thermal breaks and envelope | Designed for the climate zone the building is going to |
ifHaus issues the project-specific values with the structural package. We do not publish fixed figures here, because a number that is right for one site is wrong for another.
The standards that govern it in North America
Light gauge steel framing is a fully codified system in the United States and Canada. If you are evaluating a supplier, these are the references the engineering package should speak to.
AISI S240
The North American Standard for Cold-Formed Steel Structural Framing. It covers design and installation of members and connections in cold-formed steel light-frame construction — floor and roof systems, structural walls, shear walls, strap-braced walls, diaphragms and trusses — and sets minimum inspection and testing requirements. Referenced by the IRC and IBC.
ASTM A653 and coating designation
Governs the zinc coating on the steel sheet. G90 (Z275) is the common benchmark for structural cold-formed framing members in North America. Coating class is a corrosion-exposure decision, so it is specified per project rather than assumed.
IRC / IBC as adopted locally
The building code edition your state or municipality has adopted is what the structure is ultimately engineered to. This is also why modular approval in the United States is granted state by state rather than federally.
CSA A277 (Canada)
The Canadian certification procedure for prefabricated buildings, modules and panels. It does not contain technical requirements itself — it is the procedure for certifying that a factory-built module complies with the applicable building code. Factories outside Canada are eligible for certification.
Light gauge steel versus wood framing
Wood framing is the North American default, and for good reasons. Here is where steel differs — including where wood has the advantage, because a comparison that only runs one way is not useful to anyone.
| Light gauge steel | Wood framing | |
|---|---|---|
| Dimensional stability | Does not warp, shrink or twist with moisture | Moves with moisture content; shrinkage is designed around |
| Combustibility | Non-combustible material | Combustible; protected by assembly design |
| Rot and insects | Not a food source; no termite or fungal decay | Requires treatment and detailing in exposed conditions |
| Corrosion | Depends entirely on the galvanized coating and detailing | Not applicable |
| Thermal bridging | Steel conducts heat; thermal breaks are a required design element | Lower conductivity; simpler envelope detailing |
| Strength-to-weight | High — lighter frame for the same load | Lower |
| Trade familiarity | Specialist crews; fewer available locally | Universally available crews |
| Factory precision | Roll-formed to tight tolerance; suits factory production | Wider tolerance; suits site work |
Thermal bridging is the honest weakness of steel framing, and it is solved by envelope design rather than ignored. A supplier who does not raise it is not being straight with you.
Three systems that get confused
When a buyer searches for a steel home, three quite different products come back. Knowing which one you are looking at has to come before comparing prices.
Light gauge steel framing
Cold-formed galvanized profiles as the load-bearing frame, engineered per project, built out with insulation, services and finishes like any house. This is what ifHaus builds.
Heavy steel structure
Hot-rolled beams and columns. The right answer for long spans and multi-storey commercial buildings, and heavier and costlier than necessary for a single-family house.
Container conversion
A shipping container shell adapted into living space. Dimensions are fixed by the container, insulation is constrained by the wall build-up, and the structural logic is entirely different from a framed system.
Frequently asked questions
What is light gauge steel framing?
A structural system built from cold-formed galvanized steel sheet, roll-formed into studs, tracks, joists and trusses. It carries load the way a wood-framed wall does, but with the dimensional stability and non-combustibility of steel. In North America the design and installation standard is AISI S240.
How long does a light gauge steel frame last?
Service life is set by the galvanized coating and the detailing that keeps the frame dry, not by the steel itself. That is why coating class is a project decision tied to the corrosion exposure of the location, and why a supplier should be able to tell you exactly which class they are supplying.
Is light gauge steel framing good in earthquakes?
It is widely used in seismic regions. Steel has a high strength-to-weight ratio, so the building is lighter for the same load, and it behaves predictably and ductilely under cyclic loading. The bracing and shear wall layout follow from the seismic design category of the site, which is a project calculation.
Does steel framing cause cold bridges?
Steel conducts heat far better than wood, so thermal bridging is a real design issue rather than a marketing objection. It is handled with continuous exterior insulation, thermal break strips and careful detailing at connections. Any credible steel framing package addresses it explicitly.
Is light gauge steel more expensive than wood framing?
Frame material cost is usually higher; the saving sits elsewhere — factory precision, no shrinkage rework, a lighter frame that can reduce foundation demand, and predictable schedules. Whether the total lands higher or lower depends on the project and local labour rates.
Is ifHaus AISI S240 or CSA A277 certified?
Not at present. AISI S240 is the design and installation standard the engineering package is written to, and CSA A277 is a factory certification that we would establish through an accredited body before producing for a Canadian project. We do not hold that certification today and we are not going to imply otherwise — putting it in place is part of the project path.
Ask for the technical package
If you are evaluating light gauge steel for a project, tell us the location and the scale and we will send the structural approach, the standards it is engineered to, and what the certification path looks like in your jurisdiction.