A Class 10a building under the National Construction Code is a non-habitable building, such as a private garage, carport, shed or similar structure. People do not live or sleep in it, and it is not a workplace in the way an office is. Modular stores, plant rooms, pump houses and some amenity blocks are typically Class 10a, while a site office people work in is usually Class 5; your building surveyor confirms which.
This page is for councils, schools, sporting clubs, farms, mine and energy sites, and industrial site owners across Australia buying small factory-built buildings. The problem is that Class 10a sounds like a light category, so buyers assume a shed needs little paperwork. It still needs building approval in most cases, and the moment people start working, eating or changing in it for long periods, the class can change.
What counts as Class 10a, and what does not
- Usually Class 10a: sheds, stores, garages, carports, plant and switch rooms, pump and bore houses, bin enclosures.
- Often Class 10a: stand-alone toilet and shower blocks, depending on the use and the building they serve.
- Usually not Class 10a: site offices and crib rooms people work in, typically Class 5 or 10a, confirmed by your building surveyor.
- Class 10b covers structures such as fences, masts and retaining walls, not buildings people enter.
- Any building where people sleep is a Class 1, 2 or 3 building, never 10a.
Why modular fits Class 10a buildings
Small non-habitable buildings are often needed on sites with no builder already working there: a park, a school oval, a depot, a remote pump station. A factory-built module arrives finished, with linings, doors, ventilation and electrical rough-in done, and is fixed to footings in a short site visit. That suits owners who want one delivery and one connection rather than weeks of trades on a public site.
Public programmes already buy this way. The WA Department of Education runs modular kindy, pre-primary and toilet block programs each school year, and the 2026 mid-year round was awarded on 9 September 2026 (WA Department of Education). Our page on modular public amenities and toilet blocks covers that building type in detail.
What EcoPrestige supplies
EcoPrestige supplies engineered structural steel volumetric modules, built and inspected in an offsite factory. For Class 10a uses that means stores, plant rooms, amenity modules with toilets and showers, and change room modules, supplied to builders and councils. For larger sites, see our page on ancillary buildings for industrial and logistics sites.
What does not fit
A basic farm shed or carport is usually better value as a site-built steel kit. A volumetric module earns its place when the building has linings, wet areas, services or a finish that would otherwise take several trades on site. Very large storage sheds and warehouses suit a site-built frame.
The approval path
Most Class 10a buildings need a building permit or approval. Some small sheds are exempt in some states under set conditions, but the conditions vary and an amenity block with plumbing is rarely exempt. Planning approval depends on the zone, overlays and the setback from boundaries. EcoPrestige coordinates the module design with your consultants; permit drawings are issued by the registered or licensed practitioner the state requires. In Queensland, permit drawings are issued under a QBCC licensed building designer, and in Tasmania by a licensed Tasmanian building designer. The building surveyor or certifier confirms the class and certifies. Our building permit guide for modular buildings explains the inspections.
The programme
Confirm the class and the approval, then the factory builds the module while the site is prepared: footings, power, water and sewer or a holding tank. Factory and site work run in parallel, so time on site is shorter and a public site is closed for less time.
What to send us
- 1. What the building is for and who will use it.
- 2. Whether people will work, eat or change in it, and for how long.
- 3. The site address and any council or school requirements.
- 4. Power, water and sewer available at the site.
- 5. Any drawings, photos or a sketch.
Class 10a buildings: questions buyers ask
What is a Class 10a building?
A Class 10a building is a non-habitable building such as a private garage, carport, shed or similar structure. People do not live or sleep in it.
Is a toilet block a Class 10a building?
Often, but not always. A stand-alone toilet and shower block is often treated as Class 10a, depending on its use and the building it serves. Your building surveyor confirms the class.
Is a site office Class 10a?
Usually not. A site office or crib room where people work is typically Class 5 or 10a, confirmed by your building surveyor, with Class 5 more common where people work in it every day.
Does a Class 10a shed need a building permit?
In most cases, yes. Some small sheds are exempt in some states under set conditions, but an amenity block with plumbing is rarely exempt. Check with your building surveyor or certifier.
What is the difference between Class 10a and 10b?
Class 10a is a non-habitable building such as a shed or garage. Class 10b is a structure such as a fence, mast or retaining wall.
More detail: AS 3740 wet area waterproofing.
Want to confirm the class of your shed or amenity block?
Send the site, the use and any drawings to prebuilt@ecoprestige.com.au or download our technical brochures.