Skip to main content
The Calcs.com Cold-Formed Steel (CFS) Stud/Column calculator uses a fixed analysis model: it treats the member as a cantilever, fixed at the base and free at the top. This is intentional and matches its purpose: a concentrically loaded stud or column standing up from a base connection with no restraint at the top. If you enter a uniform lateral load w (for example, wind) over the member height L, the maximum moment the calculator reports will be M = wL²/2 at the base, not the wL²/8 you get from a pinned-pinned simple span. That is a factor of 4 difference, and it is the most common reason a hand calc on a braced curtain-wall stud disagrees with the CFS Stud/Column results. CFS Stud/Column cantilever moment diagram with peak moment at the base and zero at the top

​
When the CFS Stud/Column calculator is the right tool

Use it when the member genuinely acts as a cantilever: fixed (or effectively fixed) at one end, free at the other, carrying axial load through its centroid with lateral load applied along its length. The base fixity and free top are baked into the analysis. You cannot switch them to pinned/roller inside this calculator.

​
When to use the CFS Beam calculator instead

A typical curtain-wall stud sits between a bottom track and a deflection track. It is braced top and bottom for out-of-plane wind, which is a pinned/roller simple-span condition, not a cantilever. For that case, use the CFS Beam calculator instead:
  1. Open the CFS Beam calculator.
  2. Set the supports to pinned/roller.
  3. Set the span equal to the stud height.
  4. Apply the lateral (wind) load along the span as you normally would on a beam.
The reported peak moment will then be wL²/8, matching the hand calc for a simply supported stud.
This is a modeling choice, not a units or input bug. If your CFS Stud/Column result looks about 4x higher than expected under lateral load, the mismatch is almost always cantilever vs. simple-span. Check which support condition actually applies to your member before adjusting inputs.