Building Information Modeling (BIM) Creation

Authored by Jessica Sappington, Associate AIA

So, your client wants a BIM project… but what does that mean? Do they just want a 3D model?

People always talk about BIM and 3D models in the same sentence, but BIM is more than 3D modeling. BIM is Building Information Modeling, but if you take away the word modeling, you’re left with Building Information. A BIM project catalogs the information about the building from the types of walls and foundations, to the size and style of doors and hardware, to the location of electrical conduits. This can be done without ever modeling a single element, but who doesn’t love a 3D model? Often, we understand things better when we see them in 3D, the way we see the rest of the world.

Beyond the 3D model, what else is the client looking for? What information are they trying to get out of the model? If you are fortunate, your client has a BIM guide they want to follow which will dictate what BIM deliverables they are expecting. Even better, the BIM guide will be thorough but concise and easy to understand. Perhaps they may have even provided a scope of work that details the expectations. That isn’t likely the case. Here is a brief description of some of the deliverables in ever increasing demand.

Basic - Coordination Models

At a bare minimum, the architects and engineers on the project can run the collection of BIM models from the project through clash detection programs (i.e. Navisworks), to see if there are any major clashes between systems. A clash detection program can find a sprinkler head that clashes with a light fixture, that clashes with the supply grille. No rework needs to be done in the field. Clash reports and the models themselves for record copy are the typical deliverables at this level.

Intermediate – Checks and Balances

At this level of service, a client may ask for a BIM Execution Plan (BEP), the use of a model checker and the production of Construction- Operations Building Information Exchange (COBie) spreadsheets.

A BEP is a document that describes how the BIM project will be managed, modeled, and achieved. It typically contains the project information, project phases, project contacts, a list of the modeling software to be used, along with any other pertinent information the client requires. The file may also include checklists indicating what BIM services are to be provided and when. The BEP is the map of the project which is drafted at conception of the project and updated as the project progresses.

The model checker is a quality control requirement for some BIM projects. Some modeling programs include a function for model checking that can be tailored to the client’s requirements or can make use of a client’s pre-made model checker file. Model checkers often check the quality, level of design and types of components used in the model, line styles, types of parameters, model naming conventions, and if the file has been purged of any unused components. This list is not all inclusive by any means. After modeling checking has occurred, the client can be provided with a report exported from the model checker program.

The COBie spreadsheets are exports of the building information that is stored in the model. This information is stored as parameters in the model and should be set based on your client’s requirements. This information could be any information about the building components. Typical parameters included often help with building maintenance such as the items category, installation date, serial number, and warranty start date. These parameters are typically set up during design, but are filled in during construction. The spreadsheets may be required to be exported at any stage of development though incomplete.

In addition to the BEP, model checking, and COBie spreadsheets, the client will likely require an Industry Foundation Classes (IFC) model exported from the Architect/Engineer’s program. IFC models are compatible with many BIM software programs.

Advanced – Going Beyond

Most clients are satisfied with the deliverables outlined above, but when pushing the envelope of design, BIM can help with areas like simulation, cost estimating, energy analysis and sustainability compliance. BIM models can be run through simulation for solar, wind, ventilation, and many other environmental considerations. Similarly, they can be run through energy analysis programs to optimize a building's performance and assess design options. These analyses and sustainability parameters in a model can help to identify sustainable strategies that may be easily achieved.