Posted on 7/26/2012 11:54 AM by Jeffrey Kling
Building Information Modeling done right is a wonderful time saving coordination masterwork that is now having a dramatic impact on our industry. Building Information Modeling done wrong soaks up billable hours at an unstoppable rate everywhere. Great efforts by the designer and their supporting team occur painstakingly without realizations from those making the impactful decisions. Designers must understand far more about installation characteristics and software design than ever before.
Design firms are seeing an increase in liability as well from its use. The concept of a totally coordinated design is most likely a fallacy. Construction administration might be significantly removed if done right but inaccuracies are creating unforeseen conflicts and driving up costs. My experience points to scheduling, unknown impacts of changes, and inaccurate modeling as the critical sources of wasted time and frustration.
We, as your designers, want to provide the most successful, accurate, and cost appropriate product for any client. The project schedule and incentives for early completion can put the design on edge from the earliest moments. For example, space arrangements and structural design limit routings of utilities through the building. The coordination between facility, site, and utility connections depends on the depths and locations around the building. An earthwork or site work permit occurs early in the schedule but as one aspect of the design impacts the other, it is not recommended to attempt both simultaneously.
Simply coordinate, decide, and provide the necessary information allowing the first routing for any system to be the successful and final one. Some concessions may be made knowing only minor changes might occur leaving the major items in place for the remainder of the project. The savvy among us to a degree will allot for the unknown. Conflicts, overdesign, and other problems could be simply avoided by having all the necessary information tied to thorough project scheduling.
Successful projects will have large items within the building determined early and will be constant through the duration of the project. Interconnected references between items within the model(s) can generate large amount of errors with the slightest shift. Most items reference a datum such as a wall or a floor. Previously, changes would be needed and simply happen. Now the result is added frustration and time spent correcting these problems. Some are easily fixed but others may require a large amount of reworking.
Inaccurate modeling is just that. Failure to model items appropriately thereby creating future conflicts during construction. Equipment supports, specifically a riser clamp, is one example. Supports are irregular, cumbersome, and large objects that when unsuccessfully interfacing with the surrounding construction will create problems. Some designs require the inclusion of the supports, but most will allow the installing contractor to follow a performance specification. Designing toward a specific size followed by the purchasing a different piece of equipment may also cause this. It is important for designers to relate these items to the rest of the team, allow for inaccuracies, and allot additional space for possible changes.
I purposely failed to identify the software packages utilized for my projects. In general, history now points to a repeating pattern with new and exciting software. They will not be the perfect solution to the previous woes that have plagued our past. At first they may be shells of their true functionality, however provide promise of a better method for the future. I urge anyone considering their use to remember that any new software of significant complexity will not work seamlessly, cause frustration, and require your constructive feedback.
Jeffrey Kling is mechanical engineer, Gibbens Drake Scott, Inc.