Farm sheds in Casey’s rural-residential fringe.

• 6×12m open-front hay shed: 3-bay, 4.2m eave, BlueScope C-section, Colorbond roof, one side wall sheeted. ~$15–$22K. Holds ~30 round bales.
• 9×18m enclosed machinery shed: 4 bays, 4.5m eave, two roller doors, PA door, gravel floor, strip footings. ~$28–$38K.
• 12×24m hay + machinery combined: 6 bays, 5.0m eave, open-front bays 1–3 (hay), enclosed bays 4–6 (machinery, with 4m roller doors). ~$42–$55K.
• 9×15m livestock shelter: Skillion roof, 3.0m at high side / 2.4m at low, open along one long side, internal pen division steel. ~$22–$30K.
• 15×30m portal-frame farm shed: Mid-span clear (no internal columns), 6.0m eave, two enclosed bays + four open-front, strip footings + concrete pad at machinery end. ~$60–$85K.

Spans and bay layout.

Span (gable to gable) is the clear width. Bay spacing (rafter to rafter) is the length module — usually 3m or 4m. C-section steel handles 6m, 9m and 12m spans comfortably. Anything over 12m clear typically needs portal frame — though we can extend C-section to 15m at extra purlin spec on lower-eave builds. Bay length should match how you intend to load — 3m bays for tractors and round bales, 4m bays for utes and trailers.

Open-front vs enclosed — honest tradeoff.

• Open-front: 15–25% cheaper. Hay, equipment under shelter, lambing lean-to. Adequate for most hobby-farm work.
• Enclosed: Locks up. Required for insurance on tractors, slashers, ATVs. Needed for full livestock containment. Add ~$4K–$10K depending on size for the extra wall sheeting and the door.
• Half-and-half: Common compromise. Enclose the machinery end (lockable, dry, secure) with an open-front hay end on the same roofline. Best of both, costs in between.

Footings on a farm-shed slab.

Most farm sheds don’t need a full slab. Strip footings — a 600×600×800mm concrete pad at each column base with a bolt-down base plate — then a compacted-gravel floor through the bays is the standard. We size the pads to AS 2870 for the soil class (Class M most of Casey, H1 toward Hallam Valley, P sites with piered footings on a few Lyndhurst lots). Concrete-floor the machinery bay only if you want to wash down or store anything that can leak.

Mandatory bits we don’t skip.

• AS 1170 wind-load engineering certificate (Region A, TC2 or TC3 depending on block exposure)
• Uplift bracing on open-front sheds (different to enclosed — many cheap kits miss this)
• Gutters and downpipes to legal point of discharge (City of Casey enforces stormwater on rural blocks too)
• Earth-leakage RCD on any power circuit run into the shed
• Stormwater tank connection where the block doesn’t have reticulated drainage