BIM is a revolutionary technology and process that has transformed the way buildings are designed, analyzed, constructed, and managed. Currently, an overwhelming amount of information is available about BIM, such as theories on where BIM can go, the vast array of tools available, and how BIM seems to be the answer to all the problems facing a construction manager (CM). Although some of this information is useful, often it inundates potential users because the information all seems to meld together.
BIM has become a proven technology. What it can do and the concepts associated with BIM taken out of context, however, can become misleading and frustrate users and owners alike to the point of not wanting to use this technology again on future projects. This not only hurts the future growth of BIM technology, but it inhibits users from getting involved and sharing their experiences with others in the BIM community to further refi ne lessons learned and best practices.
BIM works. While there currently are a number of ineffi ciencies that will continue to be refi ned, BIM as a technology is no longer in its infancy and has started to produce results for the AEC/O industry all over the world. The new frontier for BIM and for its users is to defi ne a new process that better enables this new technology.
BIM and the Team
What does BIM mean to other team members? Architects use it to more effi ciently model their designs (it’s not drafting anymore), to generate the documents that are required of them, and to perform a host of other tasks. Designers using BIM can quickly generate rendered perspective views and animations to better communicate the project to the owner or local municipalities. Engineers can model mechanical and electrical designs to evaluate how a system will perform. Sustainability consultants, architects, and engineers can measure day lighting, recycled and reused material content, and solar orientation. In essence, any physically modeled object can be created, infused with data, analyzed, scheduled, and tested.
Existing Delivery Methods
So, why does BIM matter to contractors? To really understand the answer to this question, you need to first look at current processes to see how information is shared, what types of technologies are being used, and what types of project delivery methods are being used. There are currently four project delivery methods:
- Integrated project delivery(IPD).
Design-bid-build is one of the most traditional types of delivery methods practiced today. The basic concept behind design-bid-build is a linear process. The owner contracts with the architect to develop a program and then further develops the design using mechanical, electrical, and plumbing engineers. After the design has been solidifi ed, the project moves into construction documentation, with the understanding that the design team will produce completed construction documents for the project to be issued to a number of general contractors to bid on. The role of the general contractor on this type of delivery is to take the documents and specifi cations and work with subcontractors to defi ne their relevant scope of work and deliver a bid for the project.
Using these subcontractors’ estimates, the general contractor then compiles a completed bid. This bid is then delivered to the owner, and at this point all other bids on the project are opened either privately or publicly depending on the project type. The
owner then awards the general contractor the project’s contract based upon price to complete the project.
The design-bid-build delivery method has these problems:
If a contractor has been consulted to complete an estimate on the project during construction documentation, the project may go over its scheduled delivery date because of additional drawing time due to value engineering.
- It assumes that cheaper is better. Although that assumption might be correct in regard to cost, it is not necessarily accurate in regard to project quality or the ability of the contractor to adequately perform the work or collaborate with the team.
- In a design-bid-build delivery it is the assumption that by promoting competition among general contractors the best possible price will be issued.
- The owner is at risk to the contractor for design errors.
General contractors’ bids on this type of project may vary wildly because of both internal and perceived external issues on the project. First, if a general contractor is backlogged and has too much work on their plate, they might bid the project higher. This contractor wants to complete the work they already have and justify the additional cost through staff adjustment, overtime, and other overhead costs to complete the work. Second, the general contractor will gauge the aptitude of the design team based on the documents. Because this is often the only means of collaboration with the design team that the contractor will have during a bid process, aside from a pre-bid meeting, they will raise or lower their costs depending on the detail and accuracy of the documents. Lastly, the contractor is at risk of not being selected. Typically general contractors spend a considerable amount of time and money on producing a bid, and there is a high risk for not being rewarded for that investment. Additionally, even if they are the low bidder on the project, the owner reserves the right to not accept any of the bids regardless of the cost. This drives some contractors to work with owners under other delivery methods that validate their investment of resources to receive a project.