If you’re running a depot, a terminal, a construction yard, or any industrial operation that needs office space on site, you’ve probably looked at demountables. Maybe you’re already leasing one.
They make sense at first glance. Quick to install. Relatively cheap upfront. No major construction project to manage.
But here’s what nobody tells you until you’ve been leasing for three years: you’re paying rent for a building you will never own.
The Real Cost of a Demountable Over 24 Months
Industry data paints a clear picture. According to Eco Prestige, conventional site sheds are rented at $2,000 to $4,000 per month per unit and accumulate $50,000 to $120,000 of rental cost over a typical 24-month build.
Government contract data tells the same story. An Australian Federal Police contract with Ausco Building Systems shows demountable hire costs of $39,500 to $61,300 per contract, with monthly hire running over $18,000 for a single unit.
Demountable Lease (Industry Average)
- Monthly lease: $2,000 to $4,000/month per unit (Source: Eco Prestige, 2026)
- 24-month cost: $50,000 to $120,000 per unit (Source: Eco Prestige, 2026)
- Delivery, installation, and removal are additional one-off costs, quoted separately based on site access (Source: SPM Group)
After 24 months: $50,000 to $120,000 spent. You own nothing.
Steel Frame Kit (Permanent Building)
Our Noosa model starts from $82,900 for the base kit (198 m²). A smaller custom design at 60 m² would cost proportionally less. You own a permanent, engineered building on a proper slab. It adds real value to your property.
By year 3, the demountable has cost more than a permanent building ever will. And it keeps costing.
Why Businesses Keep Leasing Anyway
1. “It’s quick.” Fair point. A demountable arrives in weeks. But a steel frame kit also arrives in weeks. The slab and fit-out add time, but most projects are completed in 8 to 12 weeks from order to occupation.
2. “It’s cheaper upfront.” Only if you ignore year 2, year 3, and every year after that. As SPM Group notes, leasing is only more affordable for projects under 2 to 3 years. Beyond that, buying wins on every financial measure.
3. “We might move.” If your operation is genuinely temporary, a demountable makes sense. But if you’ve been on the same site for 3+ years and you’re still leasing, you’re throwing money away.
What a Permanent Steel Frame Office Actually Looks Like
This isn’t a shed with a desk in it. A steel frame office building is a permanent structure, engineered to Australian standards, built on a proper slab, insulated, lined, and fitted out to the same specifications as any conventional office.
Who’s Already Making the Switch
- Fuel terminals and depots replacing rotating demountables with permanent administration buildings
- Construction companies tired of moving demountables between sites, building permanent offices at their home base
- Agricultural operations that need proper admin space on the farm
- Logistics and transport companies building office space into warehouse and distribution facilities
- Mining support operations replacing dongas with permanent structures at established sites
The Asset Value Argument
A demountable is an expense. A permanent building is an asset.
When you sell your property, a demountable adds zero to the sale price. It goes back to the leasing company. A permanent, engineered, certified steel frame building is a permanent improvement to the land. It adds real, measurable value.
For business owners who own their site, this is the argument that ends the conversation.
Get a Quote
Tell us what you need: size, use case, site address. We’ll come back with a design and a price.
Or call Brian direct: 0488 510 550