Model Progression Specifications – Resources

As part of my study of Model Progression Specifications (MPS), I have compiled a list of schemas I’ve come across. Model Progression Specifications are sometimes called model development specifications (MDS), or Level of Development (LOD) specifications. In order to improve an approach, we need to know what is already available. Please inform the Author (Brian Renehan) if any of the below information is inaccurate, or if there are other schemas available not listed. See the “contact” tab for details.



Last updated - 30/08/2016

Standards and Guides:

Vico (Trimble) - US
MPS (Model Progression Specification) - Vico (acquired by Trimble) – 2005 – Uses the term Level of Detail – Now in version MPS 3.0. It divides Level of Detail (LoD) into five progressive stages from LoD 100 to LoD 500.

This was one of the first formally established model progression specifications and was driven by “Vico’s 5D Virtual ConstructionTM Software” and BIM services. It integrates coordination, quantities, cost planning, project scheduling, and production control. In 2010, MPS 2.0 added Aspect Classes, which add Model Design (M), Cost (C) and Time / Schedule (S) to the matrix. Vico was the first to use the term “Model Progression Specification” and “may” have originally coined the terms 4D BIM and 5D BIM.


AIA E202TM 2008 BIM Protocol Exhibit (October 2008) used the Vico’s MPS Level of Detail schema as a template to create Level of Development. Because both use the acronym LOD, this causes huge confusion, even within academic papers. Thus, the acronym; “LOD” needs to be used with caution and always use the full name and source in the opening context. 

 Above: Extract from MPS 3.0 showing Aspects and Classes.


Open Geospatial Consortium (OGC) - International
OGC City Geography Markup Language (CityGML) Encoding Standard  - (OGC) - First Published 2006 – superseded by Version: 2.0.0 (April 2012). CityGML is an open data model and XML-based format for the storage and exchange of virtual 3D city models. It sets out 5 Levels of Detail (LoD) for 3D geospatial models, which go from LoD0 to LoD4. LoD0 is a simplified 2D building footprint, and the scale goes right up to LoD4 which includes building internal rooms and installations. CityGML is intended to be used for modeling existing conditions and thus is not linked to project design/construction stages or model element incremental developments.


The aim of the development of CityGML is to reach a common definition of the basic entities, attributes, and relations of a 3D city model. This is especially important with respect to the cost-effective sustainable maintenance of 3D city models, allowing the reuse of the same data in different application fields. Additional information is on the open geospatial website.


Above: Extract from OGC City Geography Markup Language (CityGML) Encoding Standard. The image does not show LoD0 (footprint only).

There is considerable ongoing work occurring with CityGML to remove ambiguity and provide better clarification in the goal to release version 3.0 in the near future.

Danish Enterprise and Construction Authority - Netherlands

Danish Information levels - June 2006 the Danish BIPS published the document “3D Working Method 2006” (Bips 2007). The Danish method is built upon the principle of evolving detailing. Each party will add information to the discipline model at a higher and higher level successively through the process and thus work with rising information levels within its discipline. The modeled construction objects are defined geometrically and functionally and a number of object attributes are added and specified further during the process. – The above, description is a text extract from Creating the Dutch National BIM Levels of Development – L.A.H.M. van Berlo, F. Bomhof and G. Korpershoek.

Above:  Extract from “3D Working Method 2006” (Bips 2007) showing the progressive stages.


British Standard institute - UK

BS 1192:2007, superseded by BS 1192:2007+A2:2016. It establishes collaboration protocols between construction project members. It includes the Common Data Environment (CDE), which is a managed repository and file sharing protocol. Model sharing framework, model status and suitability, model approval and authorization, and naming conventions are also covered in the document. BS 1192 is one of the required standards to comply with the UK BIM Level 1 and BIM Level 2 deliverables. The principles in BS 1192:2007 can be used in CAD (Computer Aided Design) and/or Building Information Modeling projects.

BS 1192 will likely have a big influence on the development of ISO 19650:2. Specification for information management for the capital/delivery phase of construction projects using Building information modeling (Information here) which will be released sometime in the future.

Supporting documents: Building Information Management - A Standard Framework and Guide to BS 1192 – 2010 - Mervyn Richards.


Above: Extract from BS 1192:2007+A2:2016, showing model suitability status.

ConsensusDOCS - US
301 - Building Information Modeling (BIM) Addendum – June 2008 – superseded November 2015. Is a BIM Contract addendum and includes administration rights, responsibilities, liability, insurance, intellectual property terms, Level of Development (LOD) and creating options regarding reliance upon model data. It is a US Industry alternative to the AIA digital practice documents. The updated format now references the BIMForum LOD Specification 2015 as part of its model progression specification.

American Institute of Architects (AIA) - US
E203TM, G201TM & G202TM - Originally AIA E202TM 2008 BIM Protocol Exhibit (October 2008) - superseded by AIA E203TM 2013, G201TM 2013 & G202TM 2013 combined creates the AIA’s Digital Practice Documents. AIA G202TM 2013 establishes Model Management Protocols and Processes, Level of Development (LOD), Model Authorised Uses, and provides a Model Element Table matrix.  Supported by an accompanying Guide; Instructions and Commentary to the 2013 AIA Digital Practice Documents.

Likely the best known Model Progression Specification (MPS) and is used worldwide. This system was originally developed from Vico Software’s MPS, Level of Detail concept, but changed it to Level of Development; LOD 100, LOD 200, LOD 300, LOD 400 & LOD 500. AIA coined the term Level of Development (LOD). It has become the benchmark when it comes to comparing Model Progression Specifications schemas.

US Army Corps of Engineers (USACE) - US
Minimum Modeling Matrix (M3) Version: 1.0 (2008), superseded by 1.3 (Sep-19-2014). M3 Level of Development scheme utilizes its own definitions, however, they are similar to the AIA G202TM 2013 definitions. 

The schema uses (Level of Development) LOD 100, LOD 200 & LOD 300, but, in addition, has a grade classification suffix attribute when specifying design model elements for construction documents. It also has an additional suffix symbol for an As-Built status. The scheme does not engage LOD 400 or LOD 500.

CRC Construction Innovation & Australian institute of Architects - Australia
National Guidelines for Digital Modelling – 2009 - Australia. It provides guidance for Model development phases (taken from BIPs 2007). These are from Phase 0 to 6. Phase 1 being: Briefing/Pre-design, 2; Conceptual design, 3; Schematic design, 4; Developed design, 5; Contract documents, and 6; Post construction/Facilities management. It also identifies Object data levels & Modelling implementation.


The National Guidelines for Digital Modelling was a cutting edge document at the time of publication. Unfortunately, the Australian Construction industry did not give it the attention it deserved and is now rarely referenced.


Building and Construction Authority (BCA) - Singapore
Singapore BIM Guide Version 1.0 - 2012 – This is s a reference guide that outlines the roles and responsibilities of project members when using Building Information Modeling (BIM) at progressive project stages. The document also covers Model Progression sub-sets such as Level of Detail, BIM objective & responsibility matrix, model progression workflows, required component modeling for each project stage, modeling guidelines, and quality assurance.

Above: Extract from Singapore BIM Guide Version 1.0 - 2012

Penn State – Building Smart – US
A Planning Guide for Facility Owners – Version 2.0 June 2013 – The Guide engages the AIA E202TM 2008 Level of Development schema, however, it offers an alternative approach by using additional suffixes similar to the M3 approach providing additional Information: - Suffix:
A - Accurate size & location, including material and object parameters
B - General size & location, including parameter data
C - Schematic size & location

The document also provides information on a case study which modified LOD 500 (As-built) schema, to contain information from the model elements Level of Development former state, thus, clarifying what Level of Detail the As-Built element is. i.e.:
              As-built LOD 100 would become LoD 510
              As-built LOD 200 would become LoD 520
              As-built LOD 300 would become LoD 530
              As-built LOD 400 would become LoD 540

BIMForum - US
LOD Specification 2013, 2014 & 2015. A system built on top of AIA G202TM 2013. The document provides detailed graphic images, clearly defining the Level of Detail at each Level of Development - LOD 100 to 400. The framework has also added an additional progression definition of LOD 350 (sub-contractor coordination and digital layout use). The 2015 version now contains a detailed associated attribute information matrix and a model element table template (in MS Excel). Scope limited to CSI Uniformat 2010.


Above: Extract from the BIMForum LOD Specification 2015, showing Level of Development requirements for Sewerage Piping at LOD 200, 300, 350 and 400.

British Standards Institute - UK
PAS 1192-2:2013. One of the primary capital expenditure UK BIM Level 2 documents. In section 3.30 – it covers Level of Definition:  Collective term used for and including “Level of Model Detail” and the “Level of Information Detail”.  Refer figure 20 (Pages 35 to 40) for a breakdown on Level of Definition. It is a project stage progression using CIC Scope of Services – Stages or RIBA Plan of Work 2013 and directly correlates Level of Definition with the project stage milestones. 

It covers buildings and infrastructure projects, Model reliance, output, Parametric information, Critical interfaces and logic, Construction Requirements, Project Costs, Project logistics and off-site activities, Project facilities (welfare, IT infrastructure, security etc.), onsite and offsite and associated project documents. PAS 1192-2:2013 is currently under review and the updated version will likely be released soon.


PAS 1192-2 and BS 1192:2007+A2:2016 are a requirement to achieve the UK BIM Level 2 deliverable for the UK April 4th, 2016 public sector projects. A full list of the relevant documents to achieve Level 2 BIM are on the BRE (Building Research Establishment) website – link

Above: Extract from PAS 1192-2:2013 Levels of Model Definition at each project stage.

NBS - UK
BIM Toolkit 2014 to date - NBS owned by the Royal Institute of British Architects (RIBA). The toolkit contains over 5,700 construction definitions for level of detail (including graphical illustrations) and level of information in a Uniclass 2015 format. This makes it the most comprehensive Level of Detail and Level of Information resource currently available.
It is a UK Government funded project to assist in the Government Level 2 BIM Mandate (April 4th, 2016). 

The BIM Toolkit provides step-by-step help to define; manage and validate responsibility for information development and delivery at each stage of the asset lifecycle.

Helpful resources on the BIM Toolkit website: Levels Of Definitions - Alistair Kell - Stefan Mordue.

Above: Extract from the BIM Toolkit, showing Air Conditioning Stage 4 Level of Detail modeling requirement.


General note: All the above documents and protocols are available for free on-line. Just follow the relevant links.

General project contract note
When engaging a Model Progression Specification to achieve a specific BIM enabled outcome, the contract between parties will likely need altering to accommodate this.

The AIA E203TM 2013, 301 - Building Information Modeling (BIM) Addendum and the CIC BIM Protocol (part of the UK BIM Level 2 framework) are contract addendum's, specifically suited for BIM Deliverable projects and easily accessible. All parties that are responsible for the production of Building Information Models on behalf of the Client/Employer should have the addendum incorporated into their contract/appointment. Please seek professional legal advice on the use of these addendums.
The CIOB Complex Projects Contract (for large projects) incorporates BIM deliverables directly into the main contract.

Legal advice on Model Progression:

Best practice guide for professional indemnity insurance when using building information models – by CIC/BIM INS - first edition 2013 – Section 2.4 gives some advice on using the Model Production Delivery Table (MPDT) within the UK BIM Level 2 framework.


Information only progression specifications:
The below MPS’s are non-graphical (Structure Data) orientated specifications. They only define Level of Information.

BuildingSMART
COBie - Construction and Operations Building information exchange. – June 2007 – Bill East - United States Army Corps of Engineers – Now managed by BuildingSMART. A specification used to deliver useful facility information by streamlining planning, design, construction, and commissioning activities. COBie’s official name is Facility Management Handover, Model View Definition (MVD). The COBie specification provides a data structure schema and a process of generating and releasing the data in progressive data drops.
COBie is one of the deliverables within a UK Level 2 Government project, to: BS 1192-4:2014. COBie complies with ISO 16739:2013 - Industry Foundation Classes (IFC) for data sharing in the construction and facility management industries.



Project Stages
COBie Worksheet
Schematic Design
Design Development
Construction Documentation
Construction
Attribute
X
X
Component
X
X
X
Contact
X
X
X
X
Document
X
X
Facility
X
X
X
X
Floor
X
X
X
X
Job
X
Resource
X
Space
X
X
X
X
Spare
X
System
X
X
X
Type
X
X
X
Zone
X
X
X
X

Above: Figure 0.1 – Sample COBie Data Drop Requirements at each Project Stage (source – BIM for Facility Managers – Wiley – Edited by Paul Teicholz)

Veteran Affairs (US)
BIM object element matrix – 2010 - is part of the VA BIM Guide.  The matrix identifies the Level of Development for non-graphical data and identifies it at LOD 100, 200, 300, 400 & 500 (in line with AIA E202TM 2008 BIM Protocol Exhibit). It uses CSI Uniformat to classify the elements and identifies COBie related data.




Above: Extract from the VA BIM object element matrix, showing the IFC and COBie data relationships.

NATSPEC (Australia)
BIM object element matrix – 2011 – is issued by NATSPEC (Australian construction specification writing group) under license of the US Veteran Affairs. It follows the same premise and approach to the VA BIM object element matrix. NATSPEC BIM object element matrix works within the NATSPEC BIM Guide.
The NATSPEC BIM object element matrix has not gained traction in the Australian construction industry.
Accompanying documentation:
BIM and LOD – NBP 001 November 2013
         

Model Progression academic related papers
Below are some noteworthy published papers on the subject in date order. If readers have published an academic noteworthy paper which focuses on Model Progression, I would be happy to list it below. Model Progression is a subject matter which requires considerable further academic research, and I encourage researchers to look into this area.

SIGABIM: a framework for BIM application -  André Monteiro & João Poças Martins – 2012



Creating the Dutch National BIM Levels of Development - L.A.H.M. van Berlo, F. Bomhof and G. Korpershoek- 2014

Enriching the "I" in BIM: A BIM-Specifications (BIMSpecs) Approach - E. Utiome, R. Drogemuller and M. Docherty – 2014

Establishing an appropriate Level of Detail (LoD) for a Building Information Model (BIM) – West Block, Parliament Hill, Ottawa, Canada - S. Fai, J. Rafeiro – 2014


Building Information Modeling (BIM): Exploring Level of Development (LOD) in Construction Projects - Aryani Ahmad Latiffi, Juliana Brahim, Suzila Mohd and Mohamad Syazli Fathi – 2015



Information management for linear infrastructures projects: complementary levels to Level Of Detail and Level Of Development - Charles-Edouard Tolmer, Christophe Castaing, Denis Morand b & Youssef Diab - 2015

BIM (Building Information Modelling): New LOD definitions. Level of Development for LOD000 to LOD600 and LOD X00 - Javier Alonso & Javier Alonso Madrid – 2015

The Information Modeling and the Progression of Data-Driven Projects - Marzia Bolpagni,
Politecnico di Milano, Angelo Luigi Camillo Ciribini, University of Brescia - 2016

Noteworthy other references and opinions

Bedrick, Jim - AEC bytes Article - http://www.aecbytes.com/
Organizing the Development of a Building Information Model - 2008 (no longer available)
A Level of Development Specification for BIM Processes – 2013 (Archived – available for a fee)

Bolpagni, Marzia - Think BIM Space - http://www.bimthinkspace.com

             The Many Faces of ‘LOD’ - June 2016

Jakson, Rob – Bond Bryan Digital -  http://bimblog.bondbryan.com/

McPhee, Antony -  Practical BIM - http://practicalbim.blogspot.com.au/
              What is this thing called LOD – 2013
              LOD, are we there yet – 2013

New Zealand BIM Handbook -   BIM Acceleration Committee with the support of the Productivity Partnership and BRANZ Building Research Levy. 
              Appendix C - Levels of Development definitions - July 2014

Renehan, Brian – BIMFix Blog - #BIMFix – http://bimfix.blogspot.com
              Developing LOD (Level of Development) – 2013
              A Review - BIMForum LOD Specification – 2015
              As-Built BIM: LOD 500 under the Microscope – 2015
              LOD – the biggest BIM con to date! – 2016
              UK BIM Level 2 Model Progression Specification – A Review - Part 1 - 2016
              UK - BIM Level 2 - A Detailed Explanation - Part 2 - 2016

Vandezande, James - All Things BIM - http://www.allthingsbim.com/
              LOD Reply: PracticalBIM – 2013



Noteworthy forum discussions:

McPhee, Antony -  LinkedIn – Group - BIM Experts

LOD – the biggest BIM con to date!

Overview:

Introduction:
There is no such thing as a perfect BIM (Building Information Modelling) protocol. Despite best efforts, Model Level of Development (LOD) from AIA G202TM 2013 may have more than just a few quirks. It may be built on several false premises. This is even more emphasized when working outside of the US, and the accompanying AIA Digital Data protocols are not engaged (that is; AIA: E203 2013, G201 2013 and G202 2013 along with A101 2007 and B101 2007).

In my posts to date on Level of Development here: (below-detailed links have been added for clarification)

  • 2013 - Developing LOD (Level of Development): A review on the changes from the AIA E202 2008 to AIA G202 2013. What improvements have occurred, and what still requires work.
  • 2015 - A Review - BIMForum LOD Specification-2015 - A review on the 2015 BIMForum LOD Draft Specification (Released April 2015). What works and what doesn't. How to make the document work for you. This review has been updated to reflect the final November 2015 Release.
  • 2015 - As-Built BIM: LOD 500 under the Microscope: Does the LOD 500 framework give clarity to the project team. This article proposes a new alternative to meet client and project teams needs.

I have tried to patch items within the AIA Level of Development framework which has not worked in the past; or refined aspects to try to get greater value on time invested. However, the more I study Level of Development, the more glitches I come across. Model Progression Specifications are a BIM project necessity, but they need to be an integral aspect of the project, becoming a pseudo project progression planning and analysis tool.


LOD BIM G202
Pushing LOD (Level of Development) off the BIM Cliff



Note: Any reference to “LOD” is inferring to the AIA’s “Level of Development” framework as per AIA G202TM 2013 and not Level of Detail.



Copyright: 

The works held within this article are the copyright of the BIMFix Blog, its author Brian Renehan and the other credited references. It may not be copied in part or in whole without the written permission of the author.

Flaws within Level of Development:

Below are some of the main flaws I’ve come across in the Level of Development framework. These comments below are based on what AIA G202TM 2013 provides along with the accompanying guide. I am taking the documents at face value and I’m not trying to fill in the gaps.


No Progression Processes:

What is the process of a model element going from one Level of Development to the next progressive Level of Development, when does it occur and whom decides?

The AIA G202TM Level of Development Model Element Table identifies the Major project milestones versus the Model Elements; who is the author, and what the proposed element Level of Development will be. So AIA G202TM covers the planned progression. It, however, does not in any way cover the execution of the elements progression. That is:  
  • Who decides when the model element reaches the next LOD level?
  • What rigor is involved in determining an element is now at the next LOD?
  • How do we manage a model element LOD being downgraded due to design changes, or unforeseen developments?
  • What is the order of events, the relationship between model elements in order to achieve closeout?
  • When prior to the project milestone does the element need to reach the required LOD status?

For a model element development specification, you would expect the AIA G202TM to have development process flow diagrams to clarify the above items. It has none, and no accompanying text providing a process explanation. BS 1192-1:2007 is a form of digital data (model and documents) development specification. It contains 7 process flow diagrams identifying progression workflows and its guide contains 22.


Planned Verses Actual:
From above we see the current AIA G202TM is limited to being a plan. A plan is just the first step. Understanding the actual progression provides real value to all involved. A model element development specification needs to be able to:
  • Track planned progression versus actual, and
  • Communicate development status on an element level.

In the Level of Development planning process, we currently break down the work into a UniFormat Level. However, design progression and resolution do not work neatly within classification systems. Some aspects of the design will be ahead, and some will be behind.

It is likely during a project progression, we will need to engage multiple levels of granularity in communicating and tracking status. These may include:
  • Building or File,
  • Zone or Floor,
  • System or Assembly,
  • Type,
  • Component, & maybe even a
  • Part level.
Understanding where we are in our progression is essential.


Authorized Use & Milestones:
It makes little sense the day an element reaches LOD n00, its Authorized Use for Analysis, Coordination, Cost Estimating and Scheduling changes dramatically from the previous day, especially as the change in status is planned to occur at the end of a milestone. How would this function in a typical progressive and iterative design environment?
Let’s look at an example design process for a Structural Beam using a BIM workflow during contract documentation:
  • Analysis: The designer will use the beams analytical model properties to analyze the element within its Structural system. The outcome is a design intent member size, with a location at known dimensional tolerances.
  • Coordination: A federation level coordination will then establish the beams exact location and potential penetrations.
  • Scheduling: 4D analysis and simulations if engaged will determine the elements construct-ability, &
  • Cost Estimating: will determine if the design solution is within budget and value management opportunities.

After each of the above steps, we may need to go back to the start of the process, due to an aspect which causes a result outside of the design intent constraints. The overall process may take several weeks, and may occur a few times in order to achieve resolution. It is a progressive process and is intended to occur prior to the stage close out; i.e. before the project milestone. However according to the AIA G202TM LOD Model Element Table; the LOD Model Element deliverable occurs at the project milestone. That’s clearly too late and a breakdown in the process.

The same issue occurs during construction. At construction stage, there are dozens of potential model releases required to align with the construction program. The construction program is likely broken up into trades / levels and/or zones, with potential model releases required for each. So the major milestone approach won’t work during construction either.

Authorized Use and Element Status:
AIA G202TM framework does not actually identify a current model element status. The intent is the model element is of LOD n00, with no sub-status granularity between. Yet, releasing model elements for “Coordination” (which is an ongoing project requirement); is very different to releasing a model element for “Cost Estimating”, which in turn is very different to releasing a model element for Fabrication. So the possible premise on how Authorized Use would operate on an actual model elements current status, will not satisfy required workflows.

No Document Control Integration:
On medium to large projects, it is preferred if a Document Management System (DMS) is utilized. These systems, often cloud-based regulate; - version control, document accessibility, document status, release and revision date, document author and recipient details.  Document and Digital Control in itself is a well-established methodology for identifying digital data progression and reliance (AIA G201TM 2013 allows for a DMS). It is typically carried out on a file or container level, however, there is no reason why technology solutions will not enable a “Model Element Control” level or potential other granularity levels.

Some of these DMS’s are expanding their services to be collaboration platforms, and facilitate model hosting, review and comments including; RFI’s and Consultant advice notices, shop drawing reviews, commissioning and sign offs.

A DMS is also a valuable tool to enforce process approval and sign-off. Without a DMS being engaged, BS 1192-1:2007 would be near impossible to manage and enforce.

Yet AIA G202TM protocols do not integrate with digital data control protocols and potential ICT (Information and Communication Technology) management systems. It is difficult to understand why, especially when DMS’s are becoming the norm? Integrating a Model Element Development Specification into a DMS could potentially remove some of the manual labor in adding the status data to the model elements.


No Project Stages Relationship:
Established project stages (i.e.: Schematic Design, Design Development, Contract Documentation, Tendering, Construction and Commissioning, Handover and Operations) are a keystone to all project deliveries. Understanding in what project stage an item was generated, dramatically changes how we rely on it. We are familiar how pricing off schematic design documentation will be very different, to pricing off a finalized contract documentation tender set. Why would the design and construction industry engage a well-established stage progression and sign-off process for the project, but have a completely separate approach just for the BIModel development?
The system has failed if we are saying a model elements development is only at LOD 200, and it is used as part of a Lump Sum Traditional Tender package. Either the Level of Development definitions is poorly worded, or work has not gone into the model element. My bet is the former. Maybe introducing a LOD 250 may resolve the issue?

Missing Lifecycle Integration:
BIM is intended to be about a building's lifecycle. However, the AIA G202TM – Level of Development framework only covers Design, Construction and Handover. Brief / Program Generation, Feasibility / Business Case Studies and Facilities operations are ignored.

No QC Relationship:
Quality Control is an integral aspect of production and data reliance, yet there is no clear relationship between LODs and QC.

Some LOD Definitions are clearly Broken - 1:
LOD 100 is just confusing. It is anything you want, that does not meet the criteria of LOD 200. Items we had no intention of modeling, we can specify as LOD 100, as we can derive them from the neighboring modeled elements. Paint is not modeled and so it is attributed to walls/ceiling/doors etc. Thus we can call it LOD 100.
If paint data is specifically required; specifying how it is to be communicated will be of much greater benefit to all involved than specifying LOD 100 on a model element table.

Some LOD Definitions are clearly Broken - 2:
Let’s look at an example of LOD 300. Generally, a LOD 300 model element is developed sufficiently to derive traditional construction documents. Its definition is “a specific system, object, or assembly in terms of quantity, size, shape, location, and orientation.”  At what point can a design consultant, who is engaged to provide “design intent” information, say; their elements have reached this criteria? Following design intent data output: due to Tendering Value Management, Client Substitutions, Contractor and Sub-Contractor substitutions and construction level coordination the element size or location may change. The design consultant can only reliably say the element has met all the design intent criteria. Thus, despite most Level of Development plans identifying 80% of the model at lump sum tender stage reaching LOD 300. No designer will be able to put their hand on their heart and say, the identified elements are at LOD 300.


Some LOD Definitions are clearly Broken - 3:
Let’s look again at LOD 300. The BIMForum LOD Specification has had to clarify the meaning of the word “Specific” to really mean “designed element” from the LOD 300 definition. The definition of Specific actually is: specified, precise, particular, explicit or definite. That indicates the designer knows exactly what element is going to be installed, including its product model information. 

Designers who are typically requested to generate LOD 300 model elements are often not placed to specify proprietary products. The BIMForum LOD Specification authors clearly see the error in the definition. Maybe the AIA should fix it, or introduce a new LOD level.

Some LOD Definitions are clearly Broken – 4
LOD 500 is of limited valued to the project participants. See this (As-Built, LOD under the microscope) extensive post of the topic of As-Built data and its appropriate uses.

Development Level depends on the Author
During a project, a design team will model a system or assembly. During construction, the sub-contractors will take responsibility of the area, and change/remodel it to meet their construction requirements.

If we take a façade or cladding system as an example. The designers may bring this assembly to LOD 300. It is handed across to the sub-contractor and modified to meet their requirements. Due to value engineering, this may have included changes that have an effect on the design. The Sub-contractor now presents the model back to the designers. The Level of Development is still LOD 300, as it does not meet the LOD 350 requirements yet.  However, the Sub-contractors model is clearly more developed and closer to the final outcome. Thus, the Development Level is also clearly dependent on the Author.


Clients LOD Misuse:
It is a rarity to have a project BIM brief generated by a building owner to correctly specify a model progression specification using the AIA G202TM 2013 framework.  The G202TM form itself would never be used outside the US anyway, however if a client is to specify Level of Development they need to provide the appropriate context. All too often we still continue to see clients request design consultants to produce LOD 300 models, despite the AIA G202TM accompanying Guide clearly stating there is no such thing as a LOD n00 model. These client’s worthless deliverable statements are a good example of how the industry clearly have not grasped model element Level of Development. 

We all know the design and construction industry is broken. It looks like the Level of Development framework is also broken?

LOD Legal Standing:
To my current knowledge, the AIA G202TM’s Level of Development (LOD) framework has never been tested before a court of law. It would be a very brave legal team which would engage it, as from this article the premise could be dismissed very quickly. Let’s assume they did. It is my opinion (and I’m not a legal expert) the important aspect to a legal decision is:
  • Has the supplier carried out their services in a professional and reasonable manner?
  • Has the supplier provided a service which meets the customers’ identified primary outcomes?
  • Are those outcomes reasonable?

If a firm is to be successfully litigated for a breach of contract, professional duty or damages; it won’t be because they failed to deliver all the model elements to LOD n00 which they had signed up to.

AIA G202TM 2013 is also intended to be used in conjunction with AIA E203TM 2013 which sets out the BIM and digital data proformas for the project. If these are not included, a BIM and Digital Data-centric project contract will need to be engaged to adequately cover these areas. I have not seen or heard of such a contract to date in the Australasia region.

Value to the Project Participants:
If you have ever spent hours filling out a model element table (all 2500 cells just for SD, DD & CD – from the BIMForum LOD 2015 Specification template), you start to ponder are you really getting value for all your work. As the model element table will be part of the BIM Execution Plan, it is likely it will spend most of the project time on a shelf.  At the end of each milestone, is there going to be any checks and balances to see if the planned LODs have been delivered? Is it not too late at the end of the milestone? If the model element progression specification was directly linked to the project program and plan of works, would that not be of much greater value to everyone!

Not an Integral Aspect of Project Delivery:
For a model element progression specification to be truly valuable, it requires being engaged as the default virtual project progression measurement tool. We thus need to be able to track and report on model elements at all levels. These may include:
  • Revision status,
  • Layout planning status,
  • Analysis status,
  • Coordination status,
  • Costing status,
  • Specification and Scheduling status,
  • Graphical status for display in PDF outputs,
  • Fabrication or Product selection status,
  • Installation status,
  • Commissioning status,
  • Handover status.

The AIA G202TM Level of Development will never be able to be engaged to meet all these approaches. It currently can’t even integrate with PDF drawings, schedules and specifications which may have been generated directly from the model itself.


Level of Development is trying to do too much:
Level of Development is endeavoring to make an often haphazard design and construction development process simple. It ends up over simplifying it. It tries to combine, Level of detail, Level of information, model element progression, Authorized use, and release protocols into one.

No Level of Development in any other Industry:
Level of Development in its premise as a framework around certainty and reliability is unique to the Construction industry. No other industry has anything like it. All other industries engage some form of level of detail along with design/manufacturing stages and element status’ of some kind. If the aerospace and manufacturing industry, which are years ahead of the construction industry have not seen the need for the premise behind Level of Development, why have we?

The UK BIM framework dismissed Level of Development:
In 2011, the UK Government decided it would create a 5-year plan to enable BIM processes to generate efficiencies, productivity gains, cost savings, reduced building carbon footprint and set the UK as industry leaders in BIM to enable the export of expertise. Industry experts along with funding was assembled to develop the required framework across the entire project to enable a BIM workflow. The parties involved obviously did not see the benefit in the premise behind the AIA’s Level of Development, the BIM Level 2 framework including, BS 1192:2007+A1:2015 & PAS 1192:2-2013, does not mentions Level of Development approach in any way.

Level Of Development Conclusion:

The AIA’s Level of Development when first brought out in 2008 was a bold and ambitious premise. It set out to revolutionize how we think about digital model progression in the construction industry. Unfortunately, the schema authors failed to integrate the progression into how projects are actually run, over simplified the progression approach and failed to add real value to all involved.

For anyone in the construction sector who are working outside the US and are not engaging the relevant AIA accompanying proformas (or similar equivalent), I suggest you start to investigate alternative framework to Model Element Progression approaches.

It’s time to push Level of Development off the cliff and look for a model progression specification which might actually work.