Sheds, Barns and Shacks

For quick estimate of the size of c-section frame to use for a gable roof building used as either a shed, barn or holiday shack the following quick design aids are available.

  1. Frame Selection Charts for Cold-formed Steel Sheds
  2. Design Chart Cold-formed Steel Sheds Wind Terrain Category 3 – Frames at 3m centres
  3. Design Chart Cold-formed Steel Shed Wind Terrain Category 2 – Frames at 3m centres
  4. Design Chart Cold-formed Steel Portal Frame – Frames at 6m centres

As design aids the tools only provide an estimate  and detail structural calculations area required to make final decisions. However using these tools can quickly size up materials then go check retail price and judge whether to buy a shed, or buy materials. If choose to buy materials then will need drawings and calculations. Builders and owner-builders alike have typically indicated that it is cheaper to buy the materials and get drawings and calculations than to buy a shed. The same doesn’t necessarily hold true for canopies: carports, verandahs, pergolas and patios. The issue is the size of the structure, small structures require the same calculation effort as larger structures of the same structural form. Small sheds around $2500 typically better to buy the shed, as cost of drawings and calculations will void the savings. For a large industrial shed up to 18m span, with office space, and need to match features on architectural drawings, the cost of structural drawings and calculations can be around $5500. Whilst for a gable shed around 6m span may cost from $550 to $880, depending on the features to be incorporated: for example if rip columns out to include large roller doors, then the higher fee will apply.


  1. [06/12/2017] : Original