I’ve been asked by one of my industry software provider friends to write a piece on the current state of Building Information Modeling (BIM), as it relates to estimating in the here and now. The topic has become increasingly relevant as the software driving the standard is evolving quickly. (Or is it the demand that’s drving the software, fueling the growth? No matter.) BIM is fully useful now. In fact, the oil and gas industry has been modeling its projects for thirty years, not starting construction until the model is complete, and all potential design conflicts resolved. In the building sector, BIM is largely confined to the design-build arena. Why Design-Build? Because you need to own the drawings to have sufficient access to the CAD objects, or be on a truly team-oriented project that shares its resources openly among all project players. Not found on the conventional (read archaic) low-bid project!
To the uninitiated, the BIM standard (also known as Virtual Design & Construction, or VDC) requires”intelligent” design objects, rather than mere lines on the digital plan page. These objects contain rich data including material dimensions, quantities, and types, to name just a few attributes that sets modeled objects apart from conventional 2-D CAD lines. The 3-D model can be rotated and viewed from any angle, including virtual walk-through capability. Additionally, built-in clash-detection attributes prohibit drawing ducts through windows, or electrical lines through ducts. It has evolved to the point of “5-D” technology: following the more familiar 3-D design standards, “4-D” designates Time (project scheduling) data within the model, and “5-D” the material takeoff quantity information, all built in to the drawings!
So why doesn’t everybody do it? Several reasons: High initial Cost is followed by a steep Learning Curve, and topped off with multiple competing and Incompatible Software Standards. Real world project experiences include glowing tales of months and millions shaved off projects. But likewise we hear some horror stories of high investment with puny returns. Unless the entire project team is on board utilizing the same tools, those without are at a considerable disadvantage. All major subs need to have fully compatible software, which doesn’t happen on many projects under $50mm. And even with the resources and willingness to do all of the above, the top three competing software tools are incompatible with each other. AutoDesk Revit doesn’t talk to Bentley, and neither works with Vico. The Army Corps of Engineers mandated a year ago that Bentley and Autodesk must adhere to a common comapatible standard, but nobody I know has seen it yet.
So how does this relate to estimating? Tools which interface between the model and estimate applications are becoming increasingly available, in both proprietary and software-neutral platforms. US Cost, Win Estimator, Bentley, and Vico have authored their own dedicated tools to map and import the quantity takeoff information into their estimating applcations. Sage Timberline requires a third-party interface, such as Innovaya’s Visual Estimating to import the data. The speed of this software is truly amazing. I’ve watched Innovaya read complex models, and execute literally days of quantity takeoff in minutes into a Timberline estimate. It’s truly amazing. And if the model changes, simply run the takeoff again for virtually instant update of only the changed components. Which brings to light the obvious question, are we estimators dinosaurs? The answer is no, for two reasons. First, the model doesn’t contain “invisible” aspects of the project such as mobilization, supervision, temporary facilities, or necessary components such as formwork and scaffolding. Second, and perhaps even more reassuring is that it still takes a human mind to evaluate productivity, and account for weather conditions, as well as the unique project constraints and advantages that differentiate one project from another. Where we’re saving estimating hours, (and ultimately potentially reducing estimate staff requirements), is on what I call the “donkey work” of quantity takeoff. For that, I for one say good riddance!
