Frequently Asked Questions About the National BIM Standard-United States™

What is a BIM?
Why are Building Information Models important?
What is the National BIM Standard Project Committee?
What it means to me - benefits of a National BIM Standard implementation?
What problems is it meant to solve?
What happens without a standard or if the standard isn't used?
What is the difference between the National CAD Standard (NCS), and the National BIM Standard (NBIMS)?
What is the scope of NBIMS?
Will the NBIMS be tested?
How long will all NBIM Standards take to develop?
How long until useable results are available?
What are the stages of development?
What will be the final NBIMS deliverables?
Are you developing PIMs (Product Information Models)?
How can CAFM be integrated with COBie and what are the differences between IFC, COBie, MVD?
How will the Standards Committee know that work is done?
How will the Standards Committee know the NBIMS is being implemented?
How will NBIMS be funded?
How do I contribute and what are the benefits?

What is a BIM?

The National Building Information Model Standard Project Committee defines BIM as:

Building Information Modeling (BIM) is a digital representation of physical and functional characteristics of a facility. A BIM is a shared knowledge resource for information about a facility forming a reliable basis for decisions during its life-cycle; defined as existing from earliest conception to demolition.

A basic premise of BIM is collaboration by different stakeholders at different phases of the life cycle of a facility to insert, extract, update or modify information in the BIM to support and reflect the roles of that stakeholder.

The US National BIM Standard will promote the business requirements that BIM and BIM interchanges are based on:

  • a shared digital representation,
  • that the information contained in the model be interoperable (i.e.: allow computer to computer exchanges), and
  • the exchange be based on open standards,
  • the requirements for exchange must be capable of defining in contract language.

As a practical matter, BIM represents many things depending on one's perspective:

  • Applied to a project, BIM represents Information management—data contributed to and shared by all project participants. The right information to the right person at the right time.
  • To project participants, BIM represents an interoperable process for project delivery—defining how individual teams work and how many teams work together to conceive, design, build & operate a facility.
  • To the design team, BIM represents integrated design—leveraging technology solutions, encouraging creativity, providing more feedback, empowering a team.¹

NBIM standard will incorporate several elements described later in this document but the focus will be on standardized processes which define "business views" of data needed to accomplish a particular set of functions.

Why are Building Information Models Important?

Buildings cost more than they should to design, build and sustain and they take too long to deliver. We must do a better job of collaborating between the many stakeholders involved in the building process. In a recent NIST study lack of interoperability was identified as an additional cost to the owner of $15.8B annually but most in the industry feel that this number is significantly higher as the business opportunity of improved interoperability was not included. This aspect of our business can be improved greatly with better information management and business process re-engineering to create standard information exchanges between the stakeholders. This improved business model will not detract from the creative nature of facility design, but in fact profoundly improve the customer experience.

There are some immediate actions we must take in order to change:

  • Improve collaboration between information suppliers and users in the facility business
  • Provide more accurate fundamental information to support decision making
  • Provide a standard way of storing information so that it survives the test of time
  • Build data collection and sustainment of information into our business processes

The fragmented nature of our industry is a legacy of atelier and, later trade union practices which were eventually codified in legal and ethical separations between owners, designers, constructors, vendors and end-users. Even when parties to the building process began using CAD technology many years ago, business practices were still compartmentalized and the underlying communications medium was still graphical abstractions of real objects represented in drawings and specifications produced on printed media.

BIM is the evolutionary business transformation step needed to reform the capital facilities industry. Using BIM principles and practices, elements of the capital facilities industry are represented and exchanged digitally. Digital representation means that computers can be used to 'build' the capital facility project virtually, view and test it, revise it as necessary, and then output various reports and views for purchasing, fabrication, assembly, and operations. In many cases paper output may be avoided altogether when the finalized digital designs are sent directly to procurement systems and/or digital fabrication equipment.

Building Information Models (BIM) actually create facilities models within a computer. Because they are digital, computer-based models of building elements are infinitely more useful than hand or computer drafted drawings.

"Building" in this usage is a verb—referring to the entire life of a facility including conception, design, construction, functional life, remodeling and adaptive uses, and the recycling/disposal phases of the lifecycle. We also intend to go beyond this traditional life-cycle definition to include those supporting or dependant business views who need accurate facility information to do their jobs. This would include but not be limited to investments, risk management and first responders.

Current facility information technologies and techniques function with little or no standard business process definitions. Relatively recent developments of standardized database schema have begun to standardize the packaging of information but standardized business process definitions are required in order for the functional pieces and process participants to work together efficiently.

What is the National BIM Standard Project Committee?

National BIM Standards Project Committee (NBIMS) is a committee of the National Institute for Building Sciences (NIBS) Facility Information Council (FIC). The FIC mission since 1992 has been to "improve the performance of facilities over their full life-cycle by fostering a common, standard and integrated life-cycle information model for the A/E/C & FM industry. This information model will allow for the free flow of graphic and non-graphic information among all parties to the process of creating and sustaining the built environment, and will work to coordinate U.S. efforts with related activities taking place internationally".

A charter for the National BIM Standard project committee was developed in late 2005. Signatories to the Charter agree to participate in the Committee to produce the United States National Building Information Model Standard as a full partner in this development. The Charter provides full original copyright protections for individual contributions; however, members agree that the work of the Committee shall be shared freely with the other members of the team and, as a collection, the work of the Committee shall be copyrighted by NIBS not for its gain but for protection of the development teams' efforts from uncontrolled external use.

Wherever possible consensus industry and international standards development efforts, especially International Standards Organization (ISO) efforts will be recognized and incorporated into this standard so that the standard is usable by multinational organizations. However, nomenclature specific to North American business practices will be used in the US National BIM Standard. It is hoped that other countries can benefit by replacing the specific US references with their own. Once mapping to the other countries standard can occur then international interoperability can be achieved. This will then help ensure that the US is able to compete internationally on an even footing.

Within these guidelines, the Committee is knitting together the broadest and deepest constituency ever assembled for the purpose of addressing the losses and limitations associated with errors and inefficiencies in the building supply chain. The current Charter signatories (a list of which can be seen at the NBIMS website) represent most, if not all, of the identified building lifecycle constituencies as well as most of the professional associations, consortia, and technical and associated services vendors who support them.

All team members believe and agree that the development of this standard will help improve the competitiveness of the construction industry and the efficiency and effectiveness of government agencies of the United States as well as similar international efforts, by helping to ensure that information gathered throughout the life-cycle of a constructed facility is collected in a standardized manner such that it will be useful to all interested parties for all purposes throughout the life-cycle of any constructed facility.

The Committee has significant representation from government owners, private and government practitioners, vendors, and specialist professionals. Yet it is still actively seeking more involvement from, for example, private owners, A/E/C practitioners, property and facility managers, and real property professionals.

What It Means to Me - Benefits of a National BIM Standard Implementation?

BIM standards mean different things to different people.

To the owner it means that all the collective information about the mission and how a facility was intended to perform, its creation, the incorporated pieces and parts, its operational requirements, its planned and actual performance, its occupants, etc. are securely available for use and analysis throughout the life of the facility.

To individual vendors and project team members it means that facility information and the basis for contractually exchanging it in order to accomplish efficient commerce is transparently and consistently defined. It also means that during the course of commerce, required information can move quickly from one party to the next and from one application to another without requiring manual interpretation, re-keying, or risk of misinterpretation.

To all participants in the facility lifecycle it provides the opportunity to use computer-based applications to view data in three-dimensional pictures, to view performance tables in easy-to-understand visual diagrams, to discover problems and conflicts while designs are still conceptual instead of waiting until they are discovered during physical construction, to predict a lifetime of utility consumption for each of several design and engineering options in order to select the most desirable one long before the facility details are specified and built, and a host of other highly desirable opportunities. In short, it provides the opportunity to design in 'virtual' space before committing limited resources to the creation, care and feeding of a facility that will exist for perhaps fifty years or longer.

What Problems Is It Meant To Solve?

The National BIM Standards will contribute to solving problems associated with ineffective exchange of facility information.

Currently, building projects are much more expensive than necessary because they take too long and they allow and/or in some cases create too many errors. Even after projects are completed, management of facilities throughout their life is overly complicated, and can't effectively take advantage of economies that would be available if information was readily available and easily exchanged. Concepts and designs for new facilities repeat mistakes made previously, or at least don't make effective use of information from similar operations and assets already in use.

The core of these problems is not the lack of information. Generally information is readily available; but the rules for how it should be exchanged are not generally agreed and it exists in formats and/or containers that are not readily usable by computer-based applications.

In short, we want you to be able to answer this question—"If you had the chance to [____] would you take it?" Fill in the blank with any of the examples from the following section.

As mentioned NIST has estimated that at least $15.8B per year is lost due to lack of interoperability during the building supply chain (3). This loss comes from…

  • Continued paper-based business practices.
  • Lack of standardization.
  • Inconsistent technology adoption among stakeholders.
  • Redundant paper-based records management across all facility life-cycle phases.

Losses are organized into the following categories:

  • Avoidance—Redundant training and software maintenance, task-specific systems do not communicate well with each other.
  • Mitigation—Re-entry of data make redundant labor costs, need for 'coordination of information' costs, searching for information, segregation (classification) of information, downstream effects of design information applied to operations, cost of rework and scrap due to mistakes, manual re-entry of information creates work and errors, verifying information when original sources not available.
  • Delay—The consequence of avoidance and mitigation; interoperability can create more 'up-time', Delay completion of a project or time facility is not in normal operation, idle resources, delay in availability of products & services, profits lost due to delay in receiving revenues.
  • Opportunity and decommissioning costs/loses—not estimated in NIST study because they were not reliably documented but widely believed to at least equal to losses from lack of interoperability.
  • NBIMS addresses Avoidance-type problems by focusing on preventing or minimizing the impact of technical interoperability problems before they occur.
  • NBIMS addresses Mitigation-type problems by focusing on activities related to responding to interoperability problems.
  • NBIMS addresses Delay-type

The work of the NBIMS Project Committee attacks all of these issues by attacking avoidance, mitigation and delay through the following:

  • Specifically NBIMS is doing the following:
    • Support and promote Industry foundation classes for data schema development through NIBS Building Information Management (BIM) Council initiative, support and promotion of standardized classification and building information content through NIBS OMSI, and partnering with industry standards consortia to minimize the impact of proprietary applications use, maximizing inter-system communications, reducing need for some training and software maintenance.
    • Identify important common functional processes, define information exchange requirements, provide contracted exchange standards and boilerplate,
    • Work with industry organizations to develop project contracting models that mitigate risk and share rewards for interoperable project delivery approaches.
    • Make information transparent to machine search/retrieval techniques;
    • Make information transparently available to functional downstream uses
    • Promote & support with standards virtual planning, design, construction and operation including clash detection, correct material choices, performance testing which reduce errors and omissions.
    • Promote re-use of information through information and exchange standards to reduce re-keying requirements.
    • Promote single entry of information, capture and life-cycle accessibility to original source for verification.
    • Make exchanges standard and automatic to reduce cycle time thereby increasing revenue and profit potential.

What Happens Without a Standard or If the Standard Isn't Used?

If National BIM standards are not used,

  • Individuals in business and individual project teams will continue to repetitively create and re-create local, non re-usable, non-interoperable solutions to the same problems.
  • Businesses will continue to take longer than necessary to get to market with new products and services because it will take far longer than necessary for parties collaborating on a project to share their ideas and communicate specific results.
  • More errors and omissions than necessary will be incorporated into designs only to be discovered during construction where they are very costly to correct.
  • Information will continue to be re-entered an average of seven times rather than entered once and used many times.
  • Many more resources than necessary will be consumed during the life of a facility because the combined performance of materials and components wasn't known until a facility was built and operated for many years.
  • Facility occupants will work less efficiently because built-in functional and environmental constraints were not designed out during pre-construction virtual design and operations testing.
  • Even if BIM is implemented in a limited sense on individual projects it will remain proprietary and stove-piped and it will not be efficient to access and/or securely exchange information.

What is the Difference Between the National CAD Standard (NCS), and the National BIM Standard (NBIMS)?

The move from CAD to BIM is rooted in the economic and functional advantages of maturing from paper-based, redundant and proprietary paradigms to an information-based interoperable modeling paradigm which, in turn, supports the functions, users and products necessary to the lifecycle of a facility.

Simply stated, the NCS addresses paper-centric drafting as a means of producing design and construction drawings. NBIMS sets standards for typical processes and computer-based exchanges of information employed during the conception, creation, and operation of facilities. Since design and construction drawings, as well as computer-based virtual building models, are a typical product of building information modeling techniques, NCS will continue to be important as a standard for design and construction drawing output from the BIM process.

"The NCS is a product from the cooperation of the AIA, CSI, and NIBS. The NCS represents a consensus among architects, engineers, and experts from the construction industry about how to classify building design data and streamline communication among owners and design and construction project teams based on paper-centric information delivery.

The NCS defines standards for many aspects of electronic building-design data, including:

  • CAD layers
  • Organization of drawing sets
  • Drawing sheets and schedules
  • Drafting conventions
  • Terms and abbreviations
  • Graphic symbols
  • Notations
  • Code conventions
  • Plotting"²
    For more information, see the Web site at

The NCS is also preparing for an update which will incorporate its relationship to the NBIMS now that the relationships have been identified.

What is the Scope of NBIMS?

The NBIM Standards will cover business transactions between all actors during all phases of the facility lifecycle. While this sounds like an infinite undertaking, it has been estimated that approximately 250 to 300 transactions will describe 95% of the possible transactions with perhaps 150 of these representing the most important. Examples of typical transactions that are already in process are the exchange and capture of early design information, exchanges required to do automated code checking, and the exchange of 'as-is' information between the design/construction and operations phases. Additional early candidates include adopting recent industry-developed standards for structural steel and ductwork design/engineering, and pre-cast concrete design/engineering.

Diagram showing the distribution of IAI model based information to cost estimation, simulation, scheduling, portfolio management, facilities management, GIS integration, structure, energy and analysis tools, web and media standards, and the National CAD Standard

Will the NBIMS be tested?

The Committee believes it is essential to both define the required information interchange and test that various techniques and technologies can demonstrate the ability to meet these requirements. The testbed approach defines the purpose, contextual requirements, and the required data elements for an exchange both in non-technical and technical term. The non-technical explanation satisfies the need of practitioners and professionals; the technical explanation addresses the needs of application developers. The Committee does not tell software vendors how to implement the standards in their software; rather the testbed is used to verify that requirements can be met.

How long will all NBIM Standards take to develop?

It is the Committee's intent that a comprehensive standard be developed now and matured over time. The first products of the NBIMS effort are planned for publication in December 2006. Products at that time are expected to include the NBIMS Scope definition, an update to the NBIMS Process Standards and Maturity Model documents, the coverage of the release version, reference standards, and IDMs for COBIE, Preliminary Design, and Code Checking, and associated implementation guidance. The Committee's first funding for the NBIM Standard has been provided by the Charles Pankow Foundation for development of the Pre-Cast Concrete portions of the standard. This initial effort will also provide the templates for other areas of interest to further other portions of the standard. This initial effort will also fund an economic analysis of the benefits to their community.

How long until useable results are available?

This is largely dependant on contributors [you] and how quickly funds can be gathered for development of the standard. The consensus and testing while not overly taxing, does take some time. The standard will be developed using a spiral development approach. An IDM will be available for inclusion into a business processes prior to it being tested and demonstrated in commercially available software.

To this end the testing team began in early 2006 with the first testbed for NBIMS intended items. This first testbed which was initiated outside the NBIMS effort, buy now scheduled for inclusion will examine the interface between CAD and GIS. This effort (OWS-4) as well as all NBIMS testing is under the auspices of the Open Geospatial Consortium (OGC) testbed process which will be the model for all future efforts. It should be noted that sponsors are still needed for this and all future projects. Sponsorship will relieve the cost of testing from the vendors so that all vendors can participate, not only the major vendors. Therefore the first tested packages are scheduled to be available in December 2006 with the scheduled delivery of the NBIMS.

What are the stages of development?

  1. Nominate a candidate for the NBIM Standard.
  2. NBIMS Scoping Committee reviews nomination, requests revisions prior to acceptance.
  3. Work is forwarded to Development Committee where the candidate is assigned a priority and resources are solicited.
  4. When resources are available, a working group is formed.
  5. Working group follows IDM process.
  6. IDM is approved and forwarded to Testing Committee.
  7. Testing Committee manages testbed process.
  8. Testbed results are recommended to the Executive Committee for approval and release to general publication.

It is anticipated that many parallel efforts will be underway simultaneously and potentially be several groups; however coordination must be under the NBIMS Executive Committee for ultimate inclusion into the standard

What will be the final NBIMS Deliverables?

NBIM Standards will be published as human-readable documents containing sections for:

  1. Identifying the name (which describes its intent), creator and project stages for which the requirement is used.
  2. A Business Process Model Notation (i.e.: Swimlane Diagram) for the process.
  3. An overview written in non-technical prose that states the aims and content of the requirement. Identify other standards that have been adopted, incorporated and/or 'harmonized' with this one.
  4. A technical description, intended for application developers that identifies a list of information items needed to satisfy the requirement, detailed data breakdown, technical details of how data may be used, the actor supplying the data, and matches up functional parts with data elements.
  5. Description of the expected results of the exchange requirement.
  6. Boilerplate contract language (scope of work & deliverables) for incorporating the exchange requirement into an agreement between parties. This will be as comprehensive as possible as we are beginning to see new models evolve under the auspices of BIM that were not possible before.
  7. Results of testbed activities including details of functionality and intended use, testing protocol, participants, ability of applications to meet requirements, and issues identified during the testbed activity.
  8. Instructional and/or change management materials suggested for use in implementing the Standard.
  9. Statements as to the maturity of the Standard and any plans for additional development.

Are you developing PIMs (Product Information Models)?

Question: Is anything being done to develop a standard for PIM (Product Information Models) and how a BIM will receive and insert such data into its database. For instance, I want to define my door using a PIM from a door manufacturer. I cannot now download their PIM into the BIM. Yet lighting design software has been able to download IES data packages for specific products for years. So are we developing a standard for other Architectural product manufacturers to communicate their data with the BIM?

Answer: Thank-you for your well timed question. As you know from AGI32, some software companies (depending upon their discipline) have made the successful effort to productize their databases. The same holds true for steel and other specific disciplines. In the realm of more general BIM software, we have farther to go. Many product manufacturers are concerned with pricing data, options, and sustainability. This requires a larger database structure. Think about Expedia. For example: At the time of specification, multiple options to a window must be looked at, etc.

When you get the light object for simulation from a BIM product you might have to remove facets, etc. but it is a one-off item representing the decision on the options on that light I just mentioned. I don't know enough about AG132 to know if this is readily handled in their database.

McGraw-Hill continues to talk about how this can be done with their manufacturer council. Window manufacturers are moving up to add product data, but they don't fully understand the business model. Many of the BIM softwares are creating the datafields for this type of information in their objects, but it remains the users job to fill it in. This is what we want to change over time.

But the simple answer to your question is that we know this has to be done. From an NBIMS focus we must first identifying the information needed for specific tasks and in what structure. It will be easier for us to get the engineering and simulation data types.

A BIM model should and must be a product information model, and help from the industry is needed to move this agenda forward. I hope you will consider working on the NBIMS project in the area of lighting, etc. We are currently looking for the information exchanges in these areas and the data required. NBIMS this is a team effort. Different disciplines are at different points in their ability to adopt and use technologies. It is an opportunity to learn, teach and to move out of one's silo and begin to help others see where different disciplines are. In so doing we help ourselves. It is a value chain.

How can CAFM be integrated with COBie and what are the differences between IFC, COBie, MVD?

IFC is an ISO standard format through which any BIM information may be exchanged. MVD's specify the required IFC subset for a specific purposes. A MVD is the way that "i.e." project standards are communicated as part of the United States National BIM Standard (NBIMS-US). COBie is the "trade name" for a NBIMS-US that defines a minimum set of construction handover information. CAFM/CMMS software imports COBie data (in one of several formats) that can be provided by contractors at, or before, beneficial occupancy. Many different CAFM/CMMS software systems currently import COBie data.

How will the Standards Committee know that work is done?

Work on an individual portion of the standard will be complete when all the development stages are complete and the standard has been released for general publication.

The work of the NBIMS Committee will be complete when the Executive Committee determines that neither additional NBIM Standards nor support for existing standards is required. It is anticipated that this effort will take years to complete and that new business opportunities will emerge as time passes that will require modification to the business relationships established in the early development period.

How will the Standards Committee know the NBIMS is being implemented?

Committee will monitor testbed activity and publish results. Standards that are appropriately mature for use by industry will presumably be implemented by application developers, product manufacturers and distributors, and end-users of all sorts. Currently, NBIMS Committee does not plan to certify specific applications unless specifically asked to do so by the developer. The NBIMS Committee will seek funding to assist members who wish to do scholarly research, prepare papers and deliver public presentations to, for example, industry organizations, educational institutions, and businesses.

How will NBIMS be funded?

Our goal is to provide an open standard distributed to the community at no cost. Obviously there are costs in realizing such a goal and that is why we are soliciting your initial and long term support. While a significant level of effort will be provided as volunteer in-kind support from many organizations we will still have expenses. Those specific expenses are documented in the attached proforma. It is critical to our success that we provide the following:

  1. Funding for travel for out of area committee participants and subject matter experts to ensure participation from all facets of the life-cycle. While most of the work is being carried on through virtual conferencing using the web and other tools some travel is required.
  2. The ability to defray costs of vendors who will participate in the test bed. If significant funding is not provided then only the largest vendors will be able to afford the cost to implement the standard and this would limit the effectiveness and scope of penetration and offset the benefits of an open standard
  3. Offset the publication costs for editing and coordination. Editors and technical writers are required to produce consistent and high quality products. Having these resources under contract will speed the delivery to market
  4. Education—we need to provide instructors and course work to schools, conferences, associations and other forms of continuing education to help with the massive transformation involved in implementation
  5. Marketing—we need to let people know the standard exists and what to do next in their quest to improve the way they do business
  6. We need to continue the work with follow-on versions of the standard continually involving more of the facility life-cycle and beneficiaries of facility information.

How do I contribute and what are the benefits?

Hopefully from reading through the provided material you now understand the need and benefit of your timely support and how you can make a difference in the transformation of our profession. The benefits are not only to the owner in lower cost but also to every user of facility information by making work easier to accomplish and producing more meaningful results. While in-kind volunteer effort is mandatory to our success contributions and grants are also needed for expenses. If you should you need further assistance with your decision to contribute it is requested that you contact Philip Schneider of NIBS at (202) 289-7800.

Individuals and organizations providing volunteer support is also tracked and that information is provided on a continual basis on the NIBS web site.

Please take the time right now to initiate a plan to support this effort as we are moving forward to our goals but critically need your support on this industry coordinated effort to develop our countries National Building Information Model Standard.


¹ BIM: What Can It Do For Me?, Bill McNamara/Bentley Building Solutions, presented to the CADD/GIS Center Symposium 2006.

² AIA Knowledge Communities webpage, BIM (Building Information Modeling) Update, Diane Davis, September 2003.