Definition:"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."
For the professionals involved in a project, BIM enables a virtual information model to be handed from the design team (architects, surveyors, civil, structural and building services engineers, etc.) to the main contractor and subcontractors and then on to the owner/operator; each professional adds discipline-specific data to the single shared model. This reduces information losses that traditionally occurred when a new team takes 'ownership' of the project, and provides more extensive information to owners of complex structures. REVIT by AutoDesk
All three Revit products (Architecture, Structure and MEP) use *.RVT files for storing BIM models. Typically, a building is made using 3D objects to create walls, floors, roofs, structure, windows, doors ductwork, electrical systems and other objects as needed. These parametric objects- 3D building objects (such as windows or doors) or 2D drafting objects (such as fasteners)- are called "families" and are saved in .RFA files, and imported into the RVT database as needed.
A Revit model is a single database file represented in the various ways
which are useful for design work. Such representations can be plans, sections, elevations, legends, and schedules. Because changes to each representation of the database model are made to one central model, changes made in one representation of the model (for example a plan) are propagated to other representations of the model (for example elevations). Thus, Revit drawings and schedules are always fully coordinated in terms of the building objects shown in drawings.
When a project is shared between several users, a central file is created which stores the master copy of the project database on a file server on the office's LAN. Each user works on a copy of the central file (known as the local file), stored on the user's workstation. Revit manages permissions on objects by locking them in the central file, ensuring that only one user has rights to them at a time. Users can periodically synchronize their changes back to the central file and receive changes from other users.
Multiple disciplines working together on the same project make their own project databases and link in the other consultants' databases for verification. Revit can perform collision checking, which detects if different components of the building are occupying the same physical space. When setup correctly schedules can also provide information to verify the functional aspects of a building. For example the level of occupancy for the room area, as well as electric and ventilation loads.
Revit is one of many varieties of BIM software which support the open XML-based IFC standard. This file type makes it possible for a client or general contractor to require BIM-based workflow from the different discipline consultants of a building project. Because IFC is a non-proprietary and human readable format, it is archivable and compatible with other databases, such as facility management software. Rendering
When a user makes a building, room, model, or any other kind of object in Revit, they may use Revit's rendering engine to make a more realistic image of what is otherwise a very diagrammatic model. This is accomplished by either using the premade model, wall, floor, etc., tools, or making her or his own models, walls, materials, etc.. The wall- and model- making process is simple enough to pick up in a day or so. Revit 2010 comes with a plethora of premade materials, each of which can be modified to the user's desires. The user can also begin with a "Generic" material, which can be customized to a level of detail not offered by many 3D modeling programs. With this, the user can set the rotation, size, brightness, and intensity of textures, gloss maps (also known as shinemaps), transparency maps, reflection maps, oblique reflection maps, hole maps, and bump maps, as well as leaving the map part out and just using the sliders for any one (or all or none) of the aforementioned features of textures. Anticipated future potential
BIM is a relatively new technology in an industry typically slow to adopt change. Yet many early adopters are confident that BIM will grow to play an even more crucial role in building documentation.
Proponents claim that BIM offers:
- Improved visualization
- Improved productivity due to easy retrieval of information
- Increased coordination of construction documents
- Embedding and linking of vital information such as vendors for specific materials, location of details and quantities required for estimation and tendering
- Increased speed of delivery
- Reduced costs
Green Building XML is an emerging schema, a subset of the Building Information Modeling efforts, focused on green building design and operation. Green Building is used as input in several energy simulation engines. But with the development of modern computer technology, a large number of building energy simulation tools are available on the market. When choosing which simulation tool to use in a project, the user must consider the tool's accuracy and reliability, considering the building information they have at hand, which will serve as input for the tool. Yezioro, Dong and Leitedeveloped an artificial intelligence approach towards assessing building performance simulation results and found that more detailed simulation tools have the best simulation performance in terms of heating and cooling electricity consumption within 3% of mean absolute error.
US NIST Cloud Computing Security Architectures might be used by emerging enterprises to geo-spatially (geographically) connect individuals (corporations) with actionable building information data. These NIST architecture models define compute environments wherein private (securities available only to user), public (securities open to all in-network users), community (securities offered by a project leader) and hybrid (securities offered by a corporation) objects (folders and files) can be previewed, linked, opened, printed, exported, edited, saved, renamed, copied and deleted) and exchanged (uploaded to another network or downloaded from another network).