Every shed is custom to some degree — but getting the design right upfront saves thousands in changes, compromises, and regrets. Here’s how to brief your shed builder so the first quote is close to the final build.
Step 1: Define the Primary Use
A shed designed for machinery storage has different requirements from one designed as a workshop, livable shed home, or commercial building. Be specific about the primary use — and honest about secondary uses.
Common primary uses and their design implications:
| Primary Use | Key Design Priority | Typical Size Range |
|---|---|---|
| Vehicle/machinery storage | Door size, clear span, floor area | 12m–24m span |
| Workshop | Power, lighting, insulation, concrete floor | 9m–15m span |
| Livable / residential | Class 1A compliance, insulation, amenities | 12m–18m span |
| Farm storage | Height, ventilation, access | 12m–24m+ span |
| Commercial / industrial | BCA class, fire rating, access, services | 18m–30m+ span |
Step 2: Get Your Dimensions Right
Width (Span)
The clear span is the internal width between the columns. This is the single most important dimension — it determines what fits inside. Measure your largest item and add clearance for access, turning, and future growth. See our sizing guide for detailed recommendations.
Length
Length is the easier dimension to adjust — it’s just more bays. Each bay is typically 4m–6m. More bays = more length at a relatively low incremental cost.
Wall Height
The dimension most people underestimate. Wall height determines door height, internal clearance, and the usability of the space. Going from 3m to 4m walls costs far less than you’d expect — and the extra metre transforms the building.
Step 3: Choose Your Configuration
- Gable — standard symmetrical roof. The default for most applications
- Skillion — single-slope roof. Good for lean-tos, awnings, and where height on one side matters more than symmetry
- Barn (American barn) — raised centre with lower side wings. Great visual appeal and natural zoning
- Mono-slope — like a skillion but freestanding. The roof slopes one direction
- With lean-to/awning — additional covered area attached to one or both sides of the main structure
Step 4: Doors, Windows, and Access
Think about how you’ll use the building every day, not just how it looks on the plan:
- Roller doors: standard (2.4m–3m wide) or wide (4m–6m). Motorised if you’ll use them daily. See open front as an alternative
- PA doors: personnel access doors so you don’t open the roller door every time you walk in
- Windows: natural light reduces lighting costs. Specify locations on the plan
- Louvres/vents: for ventilation without rain entry
Step 5: Future-Proof the Design
- Build 20% bigger than current needs — it’s much cheaper to add space now than to extend later
- Stub in power and water connections even if you’re not fitting out immediately
- Specify higher walls than the minimum — the cost difference is small
- Consider whether you might enclose open-front sections later — the frame needs to be engineered for this upfront
- Check council requirements before finalising — setbacks, height limits, and lot coverage can force design changes
Use the 3D Designer
The fastest way to nail your custom shed design is to build it in our free online 3D designer. Configure span, length, wall height, doors, windows, colours — then get an instant quote. Adjust and iterate until it’s right, then submit for a formal engineering quote.
