Consider the following uses of BIM and record those selected in the Project BIM Brief. Each should be systematically assessed in relation to project goals and in terms of value they will add.
- Project definition, planning and pre–design
- Architectural modelling (Design)
- Structural modelling and analysis
- MEP modelling and analysis
- Quantity take-off and cost planning
- Construction models
- Facilities management / As-built models
Modelling existing conditions
Define the extent of existing conditions to be modelled under the project details in the Project BIM Brief, e.g. within property boundaries, site plus immediately adjoining buildings and features, defined precinct. Also define the level of model detail required, e.g. block forms only, detailed modelling, photorealistic modelling. Incorporate reference point defined relative to true north and AHD. Align site with GIS information, northing, easting, etc.
Select from the following options:
- Create 3D topo surface from survey information.
- Model existing services and subsurface features from available information.
- Model geotechnical conditions.
- Integrate laser-scanned data about existing buildings, services, vegetation and features.
- Subdivide large sites into sites for individual buildings, development phases, etc as required to suit project requirements.
- Model planning setbacks, building envelopes, etc.
- Map site gradients and drainage patterns.
- Map access and circulation patterns.
- Model view corridors, privacy patterns (into and out of the site.)
- Model solar access and shade patterns.
- Model climatic influences, wind patterns, etc.
Space and equipment validation
Clients are encouraged to use Architectural Programming Software (APS) to compile their space (rooms, etc.) and equipment requirements. They are useful tools to formulate briefs and create a Program for Design (PFD.) To be truly effective these applications must be able to export and import data to and from the model.
APS also enables the BIM Team manage, track and report on spaces and equipment in the model during design and construction. This data can also be reused for facility management purposes. The purpose(s) for which floor area will be measured (program validation, leasing, floor space ratio, etc.) should be defined before modelling begins as this determines the appropriate method/s of measurement.
Space and equipment data is captured in the BIM model. All BIM modelling must preserve the field name designations and text values found in the client’s program. To do this, the final PFD for the project is electronically exported from the SPA for import and reuse in the BIM models. The export is then imported into the BIM software’s “space” tool and equipment data into “elements” or “objects” tools appropriate to the particular BIM software, or the data can be linked in a database external to the BIM software. Spaces and equipment are derived from the model and validated against the PFD electronically at each submittal stage.