More vim for BIM

Words or data: which should you use when to keep things clear for the whole team?

From the outset it was decided the government construction client would provide a ‘pull’ for the use of BIM (Building Information Modelling). But is this drive clarifying what is ­needed and when? What is meant by verifiable and compliant data? And how does it all relate to the new RIBA Plan of Work?

Data, often a number linked with units, is mostly short pieces of information, frequently without context, usually written into specifications and lists to define equipment and materials. It is essential for the purchase of materials and to construct and operate an asset. Data brings commitment and certainty, reducing the risk of misunderstanding of words and verification processes used to test completeness. 

Text documents are often used early in a project for defining outcomes, constraints, target setting and strategy. They are also used for performance specifications, eg cladding or engineering controls, and to define oper­ational processes such as cleaning or fault finding. They usually contain data.

A project moves quickly from the defining stage to the development of an increasing amount of generic data, including geometry. A lot of output is in the form of text documents which provide cohesion, inform the client and enable other team members to produce data.

By the end of the design stage output needs to be much more in the form of construction data. Suppliers and specialist contractors take performance specifications in text format and deliver design data using the proprietary ­products required for construction. Data made available at handover will inform an asset register and be supplemented by text documents for facilities management. The BIM verification process recognises text and data.

Sometimes one discipline has a different level of data definition to the others. As a result the whole team is uncertain about the validity of decisions of construction turnover is lost at discipline interface and interoperability Source: Andrew Pearson, associate director, Interserve Construction, HMYOI Cookham Wood Report

Sometimes, it is obvious at a certain work stage that one discipline has a different level of data definition and geometric detail to the others. As a result the whole team is uncertain about the validity of decisions being made both by the team and the client at that work stage. This might have happened at stages C, D and E using the previous RIBA Plan of Work because use of documents giving clarity about what should be delivered was not widespread

Making it all match

How can we align the delivery of text documents and data? A review of documents showed that across disciplines the work stages were not well aligned; they described what we did rather than delivered, focused on design professions and paid little attention to suppliers, specialist contractors, operators and clients, and gave limited emphasis to strategy and operation.

The government BIM strategy called on the supply chain to adopt common work ­stages and most significantly to identify the data and geometry deliverables at each work stage. 

This is important to ensure that the client, consultant team, construction team and operator know what they and others should expect to deliver at each work stage. A unified plan of work will make clear what each party should put into a stage report. 

More importantly from the government BIM perspective, the construction client will be able to test that the information complies with the requirements of its chosen data file and verify that information needed for decision making is in place. It has a contractual role.       

The RIBA Plan of Work 2013 will support the construction industry into the future with  eight agreed work stages.

In a digital plan of work the first task is to identify text documents for each work stage. Institutions including the RIBA are working with the Construction Industry Council to identify the text descriptions of what each discipline needs from others at each work stage, and when to deliver it. The next step will be to identify at each work stage the specific data and geometry that should accompany the text documents to move into a digital world.

 


Rob Manning, BIM task group  CIC


 

Money in the skip

30% 
of the construction process is rework

3-5%
of construction turnover is lost at discipline interface and interoperability

Source: Andrew Pearson, associate director, Interserve Construction, HMYOI Cookham Wood Report