top of page


BIMForum has released a draft of the 2016 version of the LOD Specification for public comment.


Original content and page


The BIMForum has released a draft of the 2016 version of the LOD Specification for public comment. The comment period will remain open until 9/23 – please send comments to  Comments from the industry are a vital part of the process of maintaining and enhancing the usefulness of this document and are greatly appreciated.

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 Draft for Public Comment.


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, andAIA 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 UniFormatTMand its use in the construction industry visit http://www.csinet.orgor 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.

BIM “needed now”

Written by Sandy Guthrie – 27 Jun 2016

Construction Europe


Building information modelling (BIM) is not just an add-on, according to FIEC president Johan Willemen, who told the association’s annual congress that BIM “needs to be brought into the frame now”.

The FIEC (the European Construction Industry Federation) Congress in Brussels, Belgium, focused on BIM. Willemen said, “BIM is everywhere and supports all the big policies.”

Willemen was speaking at his last congress as president, as his term in office has finished. He has now been replaced by Jean-Louis Marchand.

Willemen said that BIM underpinned major EU themes, from energy and resource efficiency, to jobs and skills, as well as the more obvious digital economy.

“Our message to policy makers is that BIM is not just an add-on, it needs to be brought into the frame now.”

With this in mind, FIEC has launched a new working group on BIM to support its national member federations, a move it said was to help share best practice among contractors on one hand and ensure that BIM achieved a high priority in EU institutions on the other.

Willemen outlined the job that needed to be done by FIEC on behalf of contractors. This included working in partnership with the public sector to ensure that BIM was adopted in an all-inclusive market in which SMEs were not left behind. He added that pioneering contractors needed to take the lead across Europe, as they already had in early adopting countries.

Strong focus

An international line up of speakers and panellists at the congress came from nine countries. In a panel discussion, there was a call for a strong focus on people, and the panel emphasised that IT, while critical to the sharing of data, tended to get all the attention, while collaboration down the value chain was the most important success factor.

It said that as the Commission had already financed an initiative for the public sector, it should now support an industry-led awareness raising effort, ensuring that the practical needs of the construction value chain received the lion’s share.

One element which was a recurring topic at the congress was that it was important for all parts of BIM and its users to speak the same language.

Also, Mårten Lindström, senior consultant of the BIM Alliance in Sweden, said that BIM had to be more attractive to younger people.

“It’s not new to young people,” he said. “It’s a way of life.”

Žiga Turk, professor in the Faculty of Civil & Geodetic Engineering at the University of Ljubljana, said that care had to be taken over what was imposed by governments.

“We don’t want a straitjacket into a particular type of solution,” he said.


Moderating the conference, Kjetil Tonning, vice president of FIEC and president of the Technical Commission, said, “Norway is no stranger to BIM. We’ve long since resolved many of the challenges common to its introduction and now it is thoroughly embedded in the industry.

“We know that different countries are going at different speeds, and we believe that FIEC can provide a common partner, bringing best practice to those contractors that are just getting started and linking contractors with other sector players, to help reduce fragmentation in the construction industry.”

The conference headline question was BIM: Rocket Science or Common Sense? Willemen addressed this by highlighting the pioneering history of an industry which was said to be far too often erroneously criticised for perceived lack of innovation.

Comparing the life-changing advances made possible by rocket science, Willemen said he was celebrating the achievements of contractors, which he said demanded “the same visionaries, great teams and investment as that other breakthrough innovation”.

He said it was perhaps more headline grabbing than the extraordinary impact construction had made on global economic development and the quality of people’s lives over thousands of years. With this in mind, BIM was but another milestone, he said.

bottom of page