Prefabricated & Modular Construction - CJK Fire & Safety Engineering

09/10/2025

Modern Methods of Construction

Modern methods of construction (MMC) encompass a wide range of innovative approaches, including prefabricated and modular building technologies as well as additive manufacturing, such as 3D-printed concrete. Unlike traditional construction, MMC involves the off-site manufacture of building elements that are then transported, assembled, and integrated with in-situ works. Design coordination is crucial, as is adequate site supervision and inspection and certification throughout the project.

There are several categories of MMC:

Prefabricated concrete systems – the most established and widely tested, particularly in commercial and infrastructure projects.
Timber-based systems – used for framed buildings.
Structural insulated panels (SIPs) – typically sandwich panels with an insulation foam core and a bonded material on either side.
Composite wall panels – composite layers of structural elements which can include insulation, cladding, windows and doors.
Prefabricated floor and roof systems – ranging from basic structural assemblies to fully finished modules.

Prefabricated and modular construction has shifted from niche to necessary. It is increasingly recognised as a solution to labour shortages, productivity constraints, sustainability targets and housing affordability. By manufacturing in controlled environments and assembling on site, projects can be delivered more quickly, with higher certainty of quality and reduced environmental impact. Australia’s demand for low to mid-rise residential buildings and public housing, coupled with manufacturer investment in advanced facilities, is accelerating adoption.

Market growth

Australia’s prefabricated construction sector is valued at around $16.8 billion, a modest share of Australia’s $560 billion construction industry according to Mordor Intelligence. Projections suggest steady growth to approximately $21.4 billion by 2030, with strong policy and investment tailwinds.

Time and cost benefits aren’t universal, but when designs are standardised and production is scaled, prefabrication can be:

Up to 50% faster to complete than traditional builds.
Up to 20% lower in direct cost, with additional savings from reduced rework, waste and preliminaries.

This efficiency profile makes prefabrication particularly attractive for social and affordable housing, aged care, education, and health projects, where speed, cost control, and quality assurance are critical.

Regulatory direction

The Commonwealth has tasked the Australian Building Codes Board with two key reforms to support the wider adoption of MMC:

Introducing nationally consistent definitions of MMC into the National Construction Code (NCC).
Launching a National Voluntary Manufacturer Certification Scheme in July 2028 to build confidence in factory production and streamline building approvals.

The reform is backed by the Government’s $900 million National Productivity Fund which aims to boost the economy, speed up housing delivery and support construction productivity.

Fire engineering & fire safety

Fire safety in MMC is fundamentally performance-based compliance with the NCC – but the assembly interfaces (between modules/panels) and factory-site split introduce extra risk points. A good strategy knits together product certification, tested details, site QA, and maintenance.

The Building Code of Australia governs fire resistance, spread of fire, egress, services, detection/alarms and sprinklers. ABCB’s Handbook: Building Confidence through Prefabrication gives practical guidance for offsite contexts.

CodeMark/WaterMark remain relevant; a voluntary MMC manufacturer certification scheme is slated to commence mid-July 2028, intended to verify NCC compliance and strengthen chain-of-responsibility across factory and site.

Fire safety considerations

Fire resistance – Demonstrate Fire Resistance Levels using AS 1530.4 fire-resistance tests for walls, floors, shafts, connections, and module-to-module joints which are often the critical path.
Internal linings & finishes – Assign Group Numbers to wall and ceiling linings in accordance with AS 5637.1 to meet NCC Deemed-to-Satisfy provisions. Leverage factory quality control for consistency to ensure the exact build-up used in testing is what is installed.
Cavity and joint fire-stopping – Treat horizontal and vertical interfaces between modules as fire-separating elements when required by the NCC. Use tested systems for control joints and services. Don’t substitute sealants or mineral wool without a matching test/configuration.
Services, penetrations & dampers – Pre-coordinate penetrations in the factory and use pre-qualified collars/wraps. Where ducts cross fire compartments, apply tested fire dampers and sleeves.
Detection, alarms & sprinklers – Design detection/alarms to AS 1670.1; ensure zone boundaries and cabling reflect the final module layout. Where sprinklers are required or selected, design/commission to AS 2118.
Facades & external fire spread – Pay attention to balconies, soffits, and set-backs that can create flame spread paths between stacked modules.
Bushfire /cyclone-prone locations – For Class 1/Class 2 low-rise in bushfire areas, meet AS 3959 for the assigned BAL, including ember attack at joints, vents and under-floor spaces. For cyclonic areas, wind load design, cyclone-rated structural fixings, roofing, cladding, and glazing requirements must be met.

Conclusion

Modern methods of construction are no longer a fringe option—they are becoming a critical delivery pathway for Australia’s housing and infrastructure needs. With billions of dollars in pipeline projects and clear government support, prefabrication and modular building are poised to become a mainstream part of the construction industry.

The fundamentals of fire safety under the NCC—resistance, spread, egress, detection, and suppression—remain constant. However, MMC introduces distinct challenges at the factory-to-site interface, where the integrity of tested systems must be maintained through transport, assembly, and finishing. Tested systems, robust documentation, and rigorous site quality assurance is non-negotiable.

For engineers and project teams, the task is to integrate fire safety from concept design through to certification and ongoing maintenance. By combining rigorous technical evidence with practical detailing and quality control, engineers can ensure that innovation in delivery does not come at the expense of safety.

9 News Australia: Potential construction breakthrough for Australia’s housing crisis – 28 July 2025.