Wall framing · Guide 3 of 5 · 4 min readUpdated
Steel stud and track dimensions: webs, flanges, mils and gauge
Understand when light steel is useful for an interior partition and why web depth, flange width, thickness and the specified assembly matter more than a gauge nickname.
Choose steel for the wall you need to build
Light steel can be convenient for a straight, non-load-bearing partition with repeated framing and a specified board system. The profiles are different from lumber: a stud fits into a matching track, and their flanges supply the board-fixing faces. Wood may be more convenient where the work depends on familiar timber blocking and connections.
A shallow profile preserves room width, while a deeper profile provides a different cavity and may suit different height or service requirements. Neither depth nor a gauge label alone proves suitability. Use the complete product designation and the appropriate limiting-height and assembly information; plan backing for cabinets, grab bars or other attached loads before boarding.
Example: trying to gain space in a narrow room
A shallower steel wall may look attractive on the floor plan. First check the wall height, lining, services, door framing and loads attached to it. If those require a different profile or reinforcement, selecting the smallest depth simply moves the problem to the next trade.
Choose steel for an interior partition
Choose Steel studs & track under Framing material. The planner changes the elevation, opening details, cut lengths and purchasing groups together. It retains your wood settings if you switch back.
This mode estimates a single non-load-bearing wall elevation. Enter the profiles and details specified for the project. The tool does not select limiting height, stud capacity, bracing, fasteners or a fire/acoustic assembly. Structural steel walls, shaftwall and moving head-of-wall systems need their own design.
Use the web depth, not a lumber nominal size
The presets below follow common Bailey drywall framing depths. Steel dimensions describe the profile; a 3⅝-inch steel stud is not the same depth as a dressed 2×4. Metric labels are rounded equivalents, not independent input sizes.
| Stud web depth | Decimal inches | Approx. millimetres |
|---|---|---|
| 1⅝ in | 1.625 | 41 |
| 2½ in | 2.500 | 64 |
| 3⅝ in | 3.625 | 92 |
| 6 in | 6.000 | 152 |
Choose the supplier's matching track for that stud depth. Availability of flange widths, thicknesses and lengths depends on the product line.
Keep the profile dimensions separate
A C-stud has lips at its flange edges; U-track has open legs. Track depth is measured inside its flanges, while the stud depth is measured outside. The schematic illustrates that fit without modelling bend radii or manufacturing tolerances.
The planner starts with a 1¼-inch flange and 1¼-inch track legs. Changing the flange changes the elevation and opening-jamb footprint. Changing web depth updates the profile and purchasing description; it does not silently change the stud grid.
| Dimension | Meaning in the planner |
|---|---|
| Stud web depth | Depth through the wall, perpendicular to the elevation. |
| Stud flange width | Visible face width used for stud stations and the drawing. |
| Track leg height | Visible height of the track leg overlapping the studs. |
| Base-metal thickness | Thickness of the steel itself, excluding coatings; entered separately for stud and track. |
Read a product designator
For a conventional designation such as 362S125-18, read the parts separately. Confirm the complete designation against the manufacturer's data.
| Part | Convention |
|---|---|
| 362 | Nominal 3⅝-inch web-depth designation. |
| S | Lipped C-section, used as a stud. T identifies track. |
| 125 | 1¼-inch flange width. |
| 18 | Thickness designation in mils; not an exact 0.018-inch measurement. |
One mil is 0.001 inch. Design thickness and minimum base-metal thickness are distinct values in product data; do not infer an exact cut deduction from the designation alone.
Treat gauge and EQ as product labels
Gauge and equivalent-gauge labels are not interchangeable thickness measurements. For example, ClarkDietrich lists ProTRAK 20 as 18 mil / 20 gauge EQ. That label does not mean 0.020-inch steel or a conventional 20-gauge thickness.
Enter the selected product's base-metal thickness in inches. The example 0.0188 means 18.8 mil; it is an editable geometric input, not a selected gauge or capacity. Stud thickness stays in the stud specification. Track thickness affects the model's stud seating and cut lengths.
Technical references
Confirm the current product literature and requirements for the material and assembly being installed.