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.

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. 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.

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" 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 dependent 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.

Information in the above section is sourced from The Building Smart Alliance website - www.buildingsmartalliance.org

In AEC and related domains, stakeholders with a wide range of business goals or governance goals want to bring "business process reengineering" into the world of AEC and facilities management. Old business processes no longer make sense when computers and networks can be deployed to do things better and faster. It's valuable to note, too, that new opportunities for profit or public service arise as information and communication technologies (ICT) are integrated into workflows.

BIM standard efforts involve standards from a variety of organizations, all of which are communicating with members and driven by pressure from stakeholders to improve efficiencies in virtually every commercial and public activity that involves the built environment. Their concerns encompass the planning, design, construction, management, renovation, repurposing, decommissioning and ultimate demolition of buildings, bridges, power stations, airports, highways, fuel storage facilities, refineries and ports. The stakeholders believe that BIM standards will save billions of dollars and an improved quality of life.

The global BIM standards will incorporate "business views" of information exchanged between AEC and owner / operator interests. The standards will build upon standards in use today, particularly:

• The International Alliance for Interoperability IFCs
• Standards of the National Institute for Building Sciences
• ISO standards
• Open Standards Consortium for Real Estate (OSCRE) standards
• Open Geospatial Consortium (OGC) standards
• The FIATECH capital investment roadmap
• Efforts like CSI OmniClass taxonomies, COBIE (Construction to Operations Building Information Exchange), etc.

In the US, the US National CAD Standard will also be one of the cornerstones as standards for 2D drawings continue to be required. Obviously, this is a diverse and voluminous collection of documents that will take considerable effort to weave together. It would be hard to imagine how this could be done, except that:

• The speed, storage capacity and bandwidth of digital technologies have become adequate for the job, and
• Web technologies, particularly the eXtensible Markup Language (XML), make
  it possible to encode such documents in such a way that relationships,
  including semantic relationships, among their diverse elements can also
  be used across stakeholder activities.

The BIM standards effort involves considerable outreach and coordination at the institutional level to gain the participation and endorsement of stakeholder organizations. It also involves technical standards work. The encoding schemas need to be agreed upon and software service interfaces, or application programming interfaces (APIs), need to be agreed upon so that interoperability is possible. Within application domains, application experts need to sift through the cumbersome superset of encoded information and settle on "application schemas" which are subsets tailored for the purposes of their particular application domains.

Information in the above section is sourced from the Open GeoSpatial Consortium website - www.opengeospatial.org