Pre-manufacturing (3D primary structural systems)
Modern Methods of Construction, Introducing the MMC definition framework, published by Ministry of Housing, Communities & Local Government (MHCLG) in 2019 defines 7 categories for MMC:
- Category 1 – Pre-manufacturing (3D primary structural systems).
- Category 2 – Pre-manufacturing (2D primary structural systems).
- Category 3 – Pre-manufacturing components (non-systemised primary structure).
- Category 4 – Additive manufacturing (structural and non-structural)
- Category 5 – Pre-manufacturing (non structural assemblies and sub-assemblies).
- Category 6 – Traditional building product led site labour reduction / productivity improvements.
- Category 7 – Site process led site labour reduction / productivity / assurance improvements.
Category 1 – Pre-Manufacturing (3D primary structural systems) is defined as:
‘A systematised approach based on volumetric construction involving the production of three-dimensional units in controlled factory conditions prior to final installation. Volumetric units can be brought to the final site in a variety of forms ranging from a basic structure only to one with all internal and external finishes and services installed, all ready for installation.
The system includes structural performance. Full volumetric units in apartment buildings can include apartment space and common area space. Mini volumetric structural units can include bathroom pods and the like which are structurally stacked and loaded.’
[edit] Related articles on Designing Buildings Wiki
- British post-war mass housing.
- Design for deconstruction.
- Design for Manufacture and Assembly (DfMA).
- MMC definition framework.
- Modern methods of construction.
- Off site, on track.
- Off-site construction.
- Off-site prefabrication of buildings: A guide to connection choices.
- Prefabrication.
- Pre-manufactured value
- Volumetric.
Featured articles and news
Change of use legislation breaths new life into buildings
A run down on Class MA of the General Permitted Development Order.
Solar generation in the historic environment
Success requires understanding each site in detail.
Level 6 Design, Construction and Management BSc
CIOB launches first-ever degree programme to develop the next generation of construction leaders.
Open for business as of April, with its 2026 prospectus and new pipeline of housing schemes.
The operational value of workforce health
Keeping projects moving. Incorporating unplanned absence and the importance of health, in operations.
A carbon case for indigenous slate
UK slate can offer clear embodied carbon advantages.
Costs and insolvencies mount for SMEs, despite growth
Construction sector under insolvency and wage bill pressure in part linked to National Insurance, says report.
The place for vitrified clay pipes in modern infrastructure
Why vitrified clay pipes are reclaiming their role in built projects.
Research by construction PR consultancy LMC published.
Roles and responsibilities of domestic clients
ACA Safety in Construction guide for domestic clients.
Fire door compliance in UK commercial buildings
Architect and manufacturer gives their low down.
The new towns and strategic environmental assessments
12 locations of the New Towns Taskforce reduced to 7 within the new towns draft programme and open consultation.
Buildings that changed the future of architecture. Book review.


















