Building information modeling (BIM) offers many benefits to the AEC industry. In my last post, “Three reasons why estimators are adopting BIM“, I pinpointed specifically how 5D BIM can be used by estimators to provide valuable cost saving strategies and greater project cost predictability.
Yet BIM, in many ways, is still in its infancy when it comes to estimating. Estimators operating within a BIM-based environment today particularly are running into challenges with take-off and specifications.
Missing take-off information
A main usability factor is a BIM project model doesn’t include all the information estimators need. A 3D model, for instance, may contain a pipe schematic with lengths, but estimators still need to refer to 2D drawings to take off the hangers. Or floor coverings may not exist in the model, but can be found on the 2D drawings. As a result, estimators may have to use multiple, unconnected 2D and 3D takeoff systems, complicating the process and increasing the chances for error.
Some 2D takeoff tools are available inside 3D BIM software. However, it’s generally acknowledged that these tools currently don’t provide the same level of capabilities estimators require for 2D production estimating work. Plus, the majority of takeoffs is still 2D and that’s not expected to change any time soon. Consequently, estimators are looking for ways to work concurrently with both 2D and 3D content during the takeoff process.
Scarcity of specs
Another estimating concern with 3D models is the lack of specifications. From a design perspective—particularly for independent architects—there may be little value to putting specs into the model. In fact, it may not be possible to build a model containing all the job specifications without impacting model size and performance. Designers may attempt to resolve this issue by creating links in the model to external specification documents. However, these links, which must be maintained by different stakeholders, can easily break as specifications change throughout the project.
Both these situations are currently limiting full adoption of BIM by estimating teams. As a technology provider, we, at Sage, have heard these concerns loud and clear and are developing ways to address estimator’s needs related to BIM. In my next post, I will share how Sage, Autodesk and eTakeoff are partnering to eliminate time-consuming workarounds and make it easier for construction teams to derive the full estimating benefits of 5D BIM.
If you are interested in integrating your estimating with BIM, contact us at BIMintegration@sage.com
About the Author
Walt Davis, estimating market manager for Sage Construction and Real Estate solutions, has spent more than 25 years providing technology solutions to construction companies. He is a Colorado native and an avid hiker, biker, and golfer. You can follow Walt on Twitter @waltdavisco