Prefabricated building

A prefabricated building is one whose parts are made in a controlled factory setting instead of being cast or built in place, leaving the site mainly for assembly. Prefabrication is not tied to one material: concrete, steel, timber or combinations of them are all common.

Types of prefabrication

• Component systems: columns, beams, floor planks and facade panels are made separately. Precast, prestressed concrete frames for industrial buildings are a typical case.
• Panelised systems: walls arrive as flat panels with openings and service routes already formed.
• Volumetric modules: a bathroom pod or an entire room is finished in the factory and craned into place.

Benefits and limits

Factory production is more precise and does not stop for the weather; site time drops and so does waste. On the other hand, transport sizes, crane access and connection details put limits on the design. Keeping joints watertight and airtight, and making sure connections behave well in an earthquake, need careful engineering.

Prefab works best when the design respects modular coordination from the outset. When a standard product has to be personalised and shown to clients, 3D models and visualization are the quickest way to explore and present the options.