20 December 2016

GraphisoftThis article is part of the Getting started with BIM series brought to you in association with Graphisoft.

In the UK BIM Level 2 is administered through a raft of standards and supporting documentation. It is these standards and documents together that define what the outputs or deliverables in a construction project following a BIM process are.

The launch of the BIM Level 2 website earlier this year is designed to make all of these documents accessible from one place with the ultimate aim being an all-encompassing document that defines this level of BIM maturity.

See also: The key ingredients of BIM Level 2

A BIM project in action

So, what outputs can you expect in a BIM project?

You will almost certainly have a number of parties all using their own authoring software to develop models and associated assets for their part of a project. This software will export to its own native file formats and these files may be shared inside of the common data environment. A data drop will provide each party’s information to the federated model where it is co-ordinated and checked for clashes. From these models you can expect the same kinds of deliverables as you would get in a non-BIM process – a set of 2D model contract documentation delivered in the form of .pdfs.

Of course, 2D documents must be derived from a coordinated, federated, clash detected set of models. The CIC BIM protocol states that if there is a discrepancy between what is delivered in the form of the models and the 2D .pdfs that it is the federated model data that should be referred to as the primary data source. You cannot just do your 2D work and then deliver a model as well – the model has to be what is delivering the 2D output in the first place.

The Government also requires COBie and this is a key differentiator between what is happening in the UK and the rest of the world. This means we must rise to the challenge of how to assemble and format asset data that can be used throughout an asset’s lifecycle.

See also: What is COBIe?

At the completion of each work stage, native software files are handed over to the client as a record of what has been done – and this must all sit within the common data environment.

These deliverables for BIM Level 2 are really just the starting point….What the standard requires is authorship of 3D models, federated for better clash detected output.  This should result in better 2D output and, in addition, the requisite date for operational management and facilities management (both now and throughout the lifecycle). Familiar stuff - and it’s only really COBie that represents a significant change.

The Key deliverables

For Level 2 BIM, the standard deliverables that a contractor would be expected to produce include:

  • Compliance with Employers Information Requirements (EIR)
  • BIM Execution Plan (BEP)
  • Common Data Environment (CDE)
  • BS (PAS) 1192 - Parts 1 to 5
  • Classification (through Uniclass 2015)
  • Digital Plan of Work (describing Level of Detail – LoD / CIC Work Stages)
  • Intelligent 3D libraries
  • Intelligent 3D models
  • 3D based collaboration
  • 3D digital survey
  • Asset performance optimisation
  • COBie

You can also see a hint to the future - with additional deliverables that are not stipulated as part of BIM Level 2 but will become increasingly important:

  • Contractor's Information Requirements
  • Clash prevention
  • 3D model validation
  • 3D model take-off
  • 3D model based meetings
  • 4D/ 5D modelling

That 4D (timing against the elements of your model) and 5D (costing elements) modelling do not form part of Level 2 BIM may at first seem strange. These activities are typically carried out by design and construction teams as required with additional requirements being placed by contractors on the supply chain to ensure the quality of 4D and 5D information.

Familiar stuff?

The key elements of BIM Level 2 are likely to be familiar to those with experience on a more traditional form of construction project. While the terminology and the format, and when they are required, may vary, there is much that remains as it always has. While the front-loading of data collation may require new ways of working and pose challenges for standardisation and co-ordination the benefits of new ways of working are clear and will, over time, become business as usual.

See also: When will BIM become BAU (Business as Usual)?