Understanding Construction Industry Abbreviations: BIM, GC, ITB, LOD, QTO, and More

Okay, welcome back. Now we're going to talk about the abbreviations that we utilize within the construction industry to simplify things—and in some instances, it might sound a little bit more complicated. But abbreviations or acronyms are very popular throughout the industry, so it's important to understand the terminology so that you can understand the conversation that's taking place or the directives and references being made by one of your coworkers.

Let's start out with BIM, Building Information Modeling. It's a whole lot of words to spell it out. But also, what is BIM? Is BIM being utilized on the project? It doesn't really matter if it is or not, but if you hear the terminology BIM, it's more than just a 3D image. It is a digital image of a project that contains metadata.

This may not be part of this class per se, but keep your eye on it. It's very important. Building Information Modeling is going to be a big part of construction in years to come—and it already is, for that matter.

Let's talk about CSI, which is the Construction Specifications Institute. This was the original 16-division structure for construction. Divisions 1 through 16, which started out with general conditions as Division 1, worked their way up to Division 16, which was electrical.

We have outgrown that by leaps and bounds, and it is now up to a 50-division MasterFormat that we'll touch on in just a moment. The next two are very important. GC, which is short for General Contractor.

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That's the contractor or the company that's going to be running the project. The other term, GCs with an apostrophe s, refers to the general conditions. Make sure that you have it clear in your mind what the differences are.

The General Contractor, or the GC, will also have general conditions, which refer to the cost for them to run the entire project. ITB—you may hear this from time to time—that's the Invitation to Bid. No one's going to bid your job unless they get an invitation, and the invitation obviously would include any documents and plans so they can provide a quote for you.

So the term ITB—you'll hear it pronounced throughout the entire industry. Typically, that's where you invite certain contractors to participate in a project with you. LODs—this comes from the drafting side of the construction design world.

Architectural design levels of development, as it's referred to—it's not uncommon to have an LOD of 100. That means it's very conceptual or schematic, so there's not enough information to do a detailed estimate on. But a good conceptual estimator will understand just enough to come up with a budget number. Typically, when it goes out to bid, it's going to be an LOD of 300 or 350.

So 300 doesn't mean that they're 100% complete documents, but an estimator can anticipate what else is required to fill in the blanks where anything may not be shown. QTO—I mentioned this earlier when we were talking about takeoff—but QTO stands for quantity takeoff. There are a number of different ways of doing it.

We touched on some of those already, but the bottom line is you cannot start an estimate without your quantity takeoff. SOG—slab on grade for concrete—is a whole lot easier to say, but understand what it means. ‘Sub’ is typically used to mean subcontractor—plain and simple.

WBS codes, as we touched on a little bit earlier, are Work Breakdown Structure codes. These are hardly ever spelled out, but they not only relate to takeoff and estimating—they're also used in scheduling and project management. We'll spend a little more time on WBS codes as we move further into the classes. Let's talk about file types.

We have a PDF, which stands for Portable Document Format, and it's ideal for drawings. The only thing is, it can sometimes carry a lot of extra metadata inside of it that could make it a little bit slow. Even the resolution could impact performance.

I'll talk about that a little more when we get into another file format, but PDFs are extremely common. They're used throughout the industry, and the beauty of it is—whatever is in that PDF format is locked in. You cannot change it.

You can enhance it by coloring over it, but you can't change the main content that was originally written for the PDF. And that's very important when it comes to drawings, documents, and specifications. A TIFF is another file type, similar to a PDF. It's a flat file—except it's even flatter.

It's almost like a snapshot. It has little to no metadata inside of it, and very often, PDFs are converted to TIFFs because they're a lot quicker to navigate. If you want to look at 300 sheets of plans and it takes three seconds to turn each page with a PDF, you may want to convert them all to TIFFs where they can just breeze right through. They're quick, they're light, but for the most part, understand that PDFs are usually the documents of choice distributed to contractors—both by the General Contractors as well as by the architects.

As far as image types go, there are a number of different file formats available. Any of them can be used to provide the quantity takeoff that you're looking for. It doesn't matter what the file type is.

It can actually be a snapshot—a physical image of something you take a picture of at a job site. So a number of different file images can be utilized for the quantity takeoff that provides the information required for an estimate.