In Victoria, the structural design of a modular building must be signed by a structural engineer registered under the Professional Engineers Registration Act (PERA). The engineer certifies the frame, the connections, the lifting points and the footings, and a registered building surveyor relies on that design to issue the building permit. Confirm the exact sign-off for your project with your building surveyor or certifier.
This page is for Victorian builders, developers, councils and homeowners planning a modular building in Melbourne or regional Victoria. The problem is that a module is a structure in its own right before it reaches site. It has to carry its own weight on a truck and on a crane, then work as part of a finished building. The engineer has to sign for all of it.
Why modular fits Victoria
Victoria has a large modular social housing pipeline. More than 350 modular social homes are planned by mid-2028 across Geelong, Ballarat, Bendigo, Ararat and Gippsland, Build Australia reported on 21 August 2026. Small second dwellings up to 60 m2 usually need no planning permit under VC253 from December 2023, though a building permit is always needed. Both suit repeated, engineered module types. See modular construction in Melbourne and modular granny flats in Melbourne.
What the structural engineer signs for
- The module frame: structural steel members, welds and bracing.
- Connections: module to module, and module to footing.
- Lifting and transport: lifting points and the loads a module takes on the road and on the crane.
- Footings: designed for the site soil and the module support points.
- Site loads: wind, snow where relevant, and any stacking of modules.
What EcoPrestige supplies
EcoPrestige supplies engineered structural steel volumetric modules, built and inspected in an offsite factory. The engineer receives structural details, module weights, lifting information and factory hold point records with photos of welds and bracing. For commercial work, we coordinate the module design with your consultants. For homes, design, permit documentation and construction are contracted by our sister company DST Project Management and Construction Pty Ltd, registered domestic builder CDB-U 72187. Our Domestic Program for homeowners explains the two steps.
What does not fit
A registered engineer will not sign a design that has not been checked against the actual site. Poor soils, steep slopes, flood overlays and tight access can each change the footing design or rule modules out. Very long spans or heavy roof loads can push the frame beyond a standard module. We tell you early if a standard module will not suit.
The approval path in Victoria
- Structural design: a PERA-registered structural engineer.
- Building permit and inspections: a registered building surveyor.
- Home energy rating: an accredited NatHERS assessor.
- Commercial building design: not a registered category in Victoria.
- Home design above the value threshold set in law: must be contracted by a registered builder; for us that is DST Project Management and Construction Pty Ltd, CDB-U 72187.
Homes are typically Class 1a, offices typically Class 5, and childcare typically Class 9b, each confirmed by your building surveyor. Our building permit guide for modular buildings explains surveyor inspections.
The programme
The engineer’s design is settled first. The factory then builds to it while the builder prepares footings, services and site access. Factory and site work run in parallel, so time on site is shorter. The engineer may inspect at the factory or rely on hold point records, as agreed with the surveyor.
What to send us
- 1. Site address and a soil report if you have one.
- 2. The building use and expected NCC class.
- 3. Plans or a sketch of the layout.
- 4. Your engineer and building surveyor, if appointed.
- 5. Access details for trucks and a crane.
Structural sign-off for Victorian modular buildings
Who signs the structural design for a modular building in Victoria?
A structural engineer registered under the Professional Engineers Registration Act. The registered building surveyor relies on that design to issue the building permit.
Does the engineer need to see the factory?
The engineer may inspect at the factory or rely on hold point records with photos, as agreed with the building surveyor.
Who contracts a modular home in Victoria?
Design, permit documentation and construction for homes are contracted by our sister company DST Project Management and Construction Pty Ltd, registered domestic builder CDB-U 72187.
Does a small second dwelling need a planning permit?
A small second dwelling up to 60 m2 usually needs no planning permit under VC253. A building permit is always needed.
Need structural sign-off sorted on a Victorian modular job?
Send the site, the use and any drawings to prebuilt@ecoprestige.com.au or download our technical brochures.