Building assembly
According to PAS 1192-2:2013: Specification for information management for the capital/delivery phase of construction projects using building information modelling (BIM), an assembly is a:
'Group of components or types to enable the reuse of standardised design or specification elements improving productivity of design and delivery as well as providing a location to hold specifications and lessons learnt in a simple and useable way. They may hold benchmark data for cost and carbon impacts.
The contents of assemblies may themselves have attributes and classifications. These properties may include key data which is attached (to the object) for use once it is placed into a model and may include cost, CO2, programme, maintenance and other key information.'
Sub-assemblies are: 'Major building elements that are manufactured offsite, potentially using other offsite manufactured components. Examples include balustrading assemblies, facade cassette panels and preassembled M&E elements.' Ref BIM Overlay to the RIBA Outline Plan of Work, published by the RIBA in 2012.
DfMA Overlay to the RIBA Plan of Work, Mainstreaming Design for Manufacture and Assembly in Construction, 2nd Edition, published by the RIBA in 2021, defines sub-assemblies as: ‘Major building elements that are manufactured off site, potentially comprising a combination of components. Examples include walls, floors, roofs, balconies, balustrading assemblies, façade cassette panels and pre-assembled M&E elements.’
The Product Platform Rulebook, Edition 1.2 March 2023, published by the Construction Innovation Hub, defines an assembly as: ‘A combination of components.’
NB: See also: Assembly area and Assembly and recreation definition.
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