The key ingredients of BIM Level 2

The fundamental ingredients required to deliver BIM Level 2 – a portfolio of standards and tools that will help drive your BIM implementation strategy.

You can find more information (and download full versions of the documents referenced) on the BIM Level 2 website , launched earlier this year to become a one-stop-shop when it comes to standards, tools and guidance on meeting the requirement.

The key ingredients for BIM implementation success

PAS 1192-2:2013
Specification for information management for the capital/delivery phase of construction projects using building information modelling

PAS 1192-2 has its origins in BS 1192-2007 but introduces new concepts including an employer’s expression of information they require from a project and the appropriate format for this information (Employer’s Information Requirements or EIR), and BIM Execution Plans (BEPs) – showing how the supply chain will meet the requirements of the EIR.

PAS 1192-3:2014
Specification for information management for the operational phase of assets using building information modelling

Building on previous 1192 publications, PAS 1192-2 develops these for use across the operational life of assets. Key concepts include:

  • Organisational Informaiton Requirements (OIR) – the information an organisation needs to run the business
  • Asset Infomation Reqirments (AIR) – the information the organisation needs about the asset it is responsible for
  • Asset Information Model (AIM) – the information or dataset used to describe an asset

PAS 1192-3 sets out the need for comprehensive and accurate information and establishes the AIM which can be used as the basis of all asset-related decision-making. This makes it of particular importance when it comes to establishing requirements for facilities managers down the line. Given the reliance on the AIM it is vital that this is kept up-to-date and accurate throughout the project.

PAS 1192-4:2014
Collaborative production of information. Fulfilling employer’s information exchange requirements using COBie. Code of Practice.

Collaborative project require information to be exchanged. PAS 1192-4 codifies expectations on what information is exchanged throughout the lifecycle of an asset. It also establishes requirements for reviewing and checking for compliance, continuity and completeness. COBie is the UK Government’s chosen information exchange schema for federated BIM Level 2, alongside graphical BIM models and .pdf documents.

PAS 1192-5:2015
Specification for security-minded building information modelling, digital built environments and smart asset management

PAS 1192-5 explores security requirements for BIM and digital built-environments and the steps required to create and cultivate an appropriate security mindset and secure culture within an organization, including the need to monitor and audit compliance. It does this by outlining cyber-security vulnerabilities and codifying an assessment process to determine appropriate levels of security for BIM collaboration.

The approach outlined in this PAS is applicable not only to projects employing BIM and the implementation and use of smart asset management, but to any built asset where asset information is created, stored, processed and viewed in digital form. It can also be applied to situations where digital survey data is captured as part of asset management or in readiness for a future project.

BS 8536-1:2015
Building for design and construction. Code of practice for facilities management (Buildings infrastructure)

BS 8536-1 aims to ensure that designers consider the expected performance of a building in use (whether new-build or refurb). It does this by involving the operator, operations team and supply chain from the outset and extending the supply chain’s involvement through to operational and after care phases. It includes briefing requirements for soft landings, BIM and post-occupancy evaluation.

BS1192:2007 + A2:2016
Collaborative production of architectural, engineering and construction information. Code of practice

BS 1192 sets out a ‘best practice’ method for developing, organising and managing production information for the construction industry by way of a disciplined collaborative process and naming schema. It provides a template for common naming conventions and approaches to collaborative working and efficient use of date in facilities management.

Building Information Model (BIM) Protocol

The BIM Protocol was published by the Construction Industry Council (CIC) in 2013 and acts as a supplementary legal agreement that can be easily incorporated into professional services appointments and construction contracts by way of a simple amendment. It identifies building information models that are required to be produced by the project team and puts in place specific obligations, liabilities and associated limitations on the use of those models. The protocol can also be used by clients to require the adoption of particular ways of working – adopting a common naming standard, for example.

Read more about the BIM Protocol on the BIM Task Group website.

Government Soft Landings (GSL) powered by BIM

GSL is a form of gradual handover for new and refurbished buildings, where the project team is contracted to watch over the building, support the occupant and to fine-tune the building’s systems, for up to three years post-completion. The link with a (Government) Soft Landings process may initially seem tenuous, but it is vital that the way the asset is used and maintained is considered during the briefing and design process to ensure best value is achieved in the operational lifecycle of an asset. The data gathered during the operational phase of an asset can be very important in helping to shape project needs through effective Employers Information Requirements (EIRs).

Read more about Government Soft Landings on the BIM Task Group website.

Digital Plan of Work (DPoW)

At each stage of a construction project there will be a series of deliverables.The digital plan of work allows an employer to define the deliverables required at each stage – from design and construction, through the maintenance and operation phases. As more information becomes known at each stage, the level of detail will increase as more information is added and shared. The digital plan of work codifies who must deliver what information and when. NBS created the NBS BIM Toolkit to allow this information to be captured and shared across project teams in accordance with the digital project lifecycle defined in PAS 1192-2.

Uniclass 2015

Uniclass 2015 is a standardised classification system for the UK construction industry covering all sectors and integrates with the digital plan of work. It exists to ensure that data is able to be indexed and structured to make it easily accessible in a common format.

It contains consistent tables classifying items of all scale from a facility such as a railway down through to products such as a CCTV camera in a railway station.

This new classification system was a key deliverable of the Innovate UK funded BIM Toolkit project. As part of this project, NBS worked with experts from across the industry to develop Uniclass 2015. This builds on previous versions and developments of Uniclass by CPI, but significantly extends the scope and responds to industry feedback to this previous work.

Find out more about Uniclass 2015.

BIM Execution Plan (BEP)

The success of your BIM project is down, in no small part, to developing an effective BIM Execution Plan.

The development of such a plan, for facilitating the management of information on a BIM project, is set out in PAS 1192-2:2013 where it is defined as a “plan prepared by the suppliers to explain how the information modelling aspects of a project will be carried out“.

The plan, often abbreviated as BEP or BxP, is developed both pre- and post- contract and is prepared as a direct response to the Employer’s Information Requirements (EIR). The EIR is in essence is the clients needs/requests for BIM on the project.

The BEP will detail the project deliverables stipulated by the contract and the information exchange requirements detailed in a BIM protocol, such as the CIC BIM Protocol (a supplementary legal agreement that is incorporated into construction and professional services contracts via a simple amendment).

What aspects should be covered?

The BEP should include:

  • Project Information
  • Roles and Responsibilities
  • BIM Objectives/Goals
  • Modelling Scope
  • Level Of Development Matrix
  • Key deliverables
  • Key project milestones
  • Project BIM Standards
  • Project Coordinates
  • Modelling Standards
  • File/Document name conventions
  • Communication & Meetings
  • Collaborative Processes
  • Data Exchange Protocols
  • Model/Data Checking
  • Model/Data Subdivision
  • Modelling Units/Tolerences
  • Attribute/parameter data requirements
  • Data Management Systems
  • Software
  • Project Specific BIM Content
  • Clash Management Plan
  • IT Requirements
  • Common Data Environments

What’s the difference between a pre- and post-contract BEP?

At tender stage, before a contract is agreed, a prospective supplier will develop a BEP with the aim of demonstrating their proposed approach, capability, capacity and competence to meet the client requirement in general terms.

Once a contract has been awarded then the winning supplier is required to submit a further BIM Execution Plan. The focus of this post-contract document is to confirm the supply chain’s capabilities.

Who is responsible for the BEP when multiple suppliers are appointed?

Where a contract has appointed a number of suppliers, there is likely to be one main BIM Execution Plan (with responsibility for its production set out in appointment documents). Any subsequent BEPs from later appointees must then dovetail with the existing main BIM Execution Plan.

Where do I start?

There are no hard or fast rules here every project has different needs so each plan should be tailored to suit. Develop a template that suits company needs as a start point or adopt a pre existing one.

Templates / Samples

Common Data Environment (CDE)

Collaborative BIM Working

A major constituent of collaborative environments is the ability to communicate, re-use and share data efficiently without loss or misinterpretation. This section summarises the principles outlined in BS1192:2007, which defines the working processes for project collaboration and efficient data sharing.

Refer also to PAS1192-2 section 9.2 for the extended Common Data Environment across the project team at Capex and Opex stages.

Common Data Environment (CDE) core principles

A Common Data Environment (CDE) process approach allows information to be shared between all members of the project team.

There are four areas relevant to a CDE as illustrated below:

Work In Progress (WIP)

Model data described as Work in Progress is that which is currently in production and has not yet been checked and verified for use outside of the authoring team.


To facilitate co-ordinated, efficient working, each party shall controlled release of information available for project-wide formal access through a shared repository or exchange protocol. These files shall be accessible by all from a central location, or replicated in the Shared Area of the project folder structure of each party.

Prior to sharing, the data shall be checked, approved and validated in line with the

BS1192 workflow.

  • Only BIM data or files that have been checked, approved and given the appropriate suitability/status code and revision shall be transferred to the Shared Area (see section 4.2 for checking process).

Refer to BS1192 section 15.3.2 figure 5 and PAS1192-2 section 9.2.3 table 3.

  • Sharing of models (iterative model exchanges) shall be scheduled and carried out on a regular basis in order that other disciplines are working to latest validated information as defined in the Project BIM Execution Plan.
  • It is recommended that individual discipline model files should be issued exactly as produced with no additional merging, or editing. All necessary references and linked files should also be issued.
  • A process for communicating changes needs to be defined. Changes to the shared models shall be effectively communicated to the team through traditional drawing issues sheets or transmittal forms, change register or other suitable notice, such as e-mail, as defined in the project BIM Execution Plan.

For indicative purposes, the Shared area is shown here as a single shaded region. This may, in truth be individual locations for each stakeholder.


Published documentation is created at agreed project milestones from the Shared information. This is a repository of “client approved” information and is not covered in this workflow.

Refer to BS1192 section 4.2.4 and PAS1192-2 section 9.2.


  • All approved information shall be stored in the designated Archive location, including shared, published, superseded and record information.
  • Archived data shall reside in logical folder repositories that clearly identify the archive status e.g. 2014-12-11 Stage 3 Detailed Design.

Refer to BS1192 section 4.2.5 and PAS1192-2 section 9.2.

What is a CDE?

The common data environment (CDE) is a central repository where construction project information is housed. The contents of the CDE are not limited to assets created in a ‘BIM environment’ and it will therefore include documentation, graphical model and non-graphical assets. In using a single source of information collaboration between project members should be enhanced, mistakes reduced and duplication avoided. Here we explore the CDE in more detail… Continue reading “Common Data Environment (CDE)”

Level Of Development (LOD) Specification

Latest Version

The BIMForum has released the 2016 version of the LOD Specification.

Updates to the 2016 version include:

  • New sections:
    • Railroad Bridge Steel
    • Railroad Bridge Precast
  • The Attribute Tables in Part II have been expanded and reformatted for clarity
  • Omniclass and Masterformat references have been added to Part I
  • All definitions in Part I were reviewed and edited for consistency
Click here to download a copy of the 2016 LOD Specification.


The Level of Development (LOD) Specification is a reference that enables practitioners in the AEC Industry to specify and articulate with a high level of clarity the content and reliability of Building Information Models (BIMs) at various stages in the design and construction process. The LOD Specification utilizes the basic LOD definitions developed by the AIA for the AIA G202-2013 Building Information Modeling Protocol Form[1] and is organized by CSI Uniformat 2010[2]. It defines and illustrates characteristics of model elements of different building systems at different Levels of Development. This clear articulation allows model authors to define what their models can be relied on for, and allows downstream users to clearly understand the usability and the limitations of models they are receiving. The intent of this Specification is to help explain the LOD framework and standardize its use so that it becomes more useful as a communication tool. It does not prescribe what Levels of Development are to be reached at what point in a project but leaves the specification of the model progression to the user of this document. To accomplish the document’s intent, its primary objectives are:

  • To help teams, including owners, to specify BIM deliverables and to get a clear picture of what will be included in a BIM deliverable
  • To help design managers explain to their teams the information and detail that needs to be provided at various points in the design process
  • To provide a standard that can be referenced by contracts and BIM execution plans.

It should be noted that this Specification does not replace a project BIM Execution Plan (BIMXP), but rather is intended to be used in conjunction with such a plan, providing a means of defining models for specific information exchanges, milestones in a design work plan, and deliverables for specific functions.

In 2011 the BIMForum initiated the development of this LOD Specification and formed a working group comprising contributors from both the design and construction sides of the major disciplines. The working group first interpreted the AIA’s basic LOD definitions for each building system, and then compiled examples to illustrate the interpretations. Because BIM is being put to an ever increasing number of uses, the group decided that it was beyond the initial scope to address all of them. Instead, the definitions were developed to address model element geometry, with three of the most common uses in mind – quantity take-off, 3D coordination and 3D control and planning. The group felt that in taking this approach the interpretations would be complete enough to support other uses.

[1] AIA Contract Document G202-2013, Building Information Modeling Protocol Form is part of a new series of digital practice documents the AIA published in June 2013. The AIA’s updated digital practice documents consist of AIA E203™–2013, Building Information Modeling and Digital Data Exhibit, AIA G201™–2013, Project Digital Data Protocol Form, and AIA G202™–2013, Project Building Information Modeling Protocol Form. For general information on the documents and downloadable samples see  For executable versions of the documents see

[2] UniFormatTM Numbers and Titles used in this publication are from UniFormatTM, published by CSI and Construction Specifications Canada (CSC), and are used with permission from CSI. For a more in-depth explanation of UniFormatTM and its use in the construction industry visit or contact CSI, 110 South Union Street, Suite 100, Alexandria, VA 22314. (800) 689-2900.

Click here to download a copy of the 2015 LOD Specification.

Click here to download a copy of the 2014 LOD Specification.

Click here to download a copy of the 2013 LOD Specification.

BIM Best Practice

To achieve technical excellence and a successful outcome to a project, it is essential that BIM information and output is carefully planned & standardised. This must involve explicit attention to management, display and quality of the design data.

Below are a number of best practice principles that will help create efficient, high quality deliverables.

BIM Execution

  • Determine project requirements for BIM, Regardless of the existence of an Client requirements. Key here is what graphical (Level of Development (LOD)) and non- graphical (Level of Information (LOI)) information is required and when.
  • A Project BIM Execution Plan (BEP) appropriate to the project stage shall be put in place that identifies who is responsible for key project tasks, outputs and model configuration and how project requirements are to be met. Check out the AEC-UK templates as a great start point.
  • BIM project reviews should be agreed and take place regularly to ensure model integrity and project workflow is maintained, to achieve the project requirements, and that the BEP is being followed and maintained.
  • It is imperative for smooth information exchange that clear guidelines are developed for internal and external collaborative working which maintain the integrity of electronic data.
  • Identify clear ownership of model elements through the life of the project.
  • Sub-divide models between disciplines and within single disciplines to avoid file sizes becoming too big or slow to operate (agree a project volume strategy in the BEP as early as possible).
  • Understand and clearly document Modelling Methodology. i.e. what is to be modelled and to what Level of Detail. Do not over model.
  • Do not over Document (be careful at early project stages in particular).
  • Define clearly the data (Level of Information (LOI)) to be incorporated into the BIM relevant to the stage.
  • Together, the LOD and LOI help to better communicate the expectations of BIM content and clarify the Level of Definition at any point in the design and construction process.
    • Level of Definition = LOD + LOI
  • Avoid disconnect between the main 3D model and 2D views or output. Revisions to the project should be made “at source” (i.e. in the model) to rather than editing the 2D to ensure the integrity of the model and coordination between the BIM and its output. Do not double up on 2D & 3D tasks, do it once in the model.
  • Outstanding warnings shall be reviewed regularly and important issues resolved.

Drawing Production

Where drawings are a product of the BIM, traditional drawing conventions still apply, for example:

  • A drawing shall contain design information solely for the purpose of the intended use of the drawing.
  • Numbers of drawings should be kept to an absolute minimum and organised in a logical manner.
  • The number of drawings should be kept to an absolute minimum and organised in a logical manner. Encourage the model to be used instead where possible.
  • To maximise efficiency, a policy of minimum detailing without compromising quality and integrity shall be adopted and repetition of details should be eliminated.
  • Avoidance of duplication is essential to ensure drawings maintain their integrity as the iterative design process progresses and amendments are made.
  • All drawing symbols used should be in line with industry standards.

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.