zachary.creachZachary Creach

A senior engineer in Holder Construction's Building Information Modeling group, Zack is responsible for multiple BIM-enabled projects in all phases of construction both on-site and remotely. Responsibilities include model data management, BIM execution planning, visual controls, 4D scheduling, constructability modeling, clash detection, hardware/software procurement and maintenance, preconstruction support including trade procurement.

All articles by zachary.creach


Top 10 BIM Blogs

This blog is just one of hundreds devoted to the latest and greatest on BIM and technology in the construction industry. Here’s a list of my top 10 favorite blogs for up-to-the-minute news, tips, and happenings in the BIM arena.


Do You Have a BIM Execution Plan?

Every successful BIM project starts with a plan. The BIM Execution Plan (BEP) is the standard document that defines the plan for the project, beginning with a kickoff meeting to get it all started. The goal in any BEP is to establish guidelines for creating, exchanging and maintaining digital project data. The document itself is
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Five Steps to Safely Open Revit Models

As a contractor, we see Autodesk Revit models all the time from design partners, precast detailers, electrical contractors, engineers, and many others. If we get a Revit model (.RVT), we try to use it as much as possible. However, while the Revit format is easy to open, files provided by external sources often generate error messages,
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How to View Decimal Units in Autodesk Navisworks

As a program originating in the UK, Autodesk Navisworks defaults to meters as its initial unit display. For first-time users based in the US, creating a point-to-point or spot coordinate measurement with meters as the default can be a bit disconcerting. Fortunately, the unit display is easy to change to a decimal format.


Why You Should Be Modeling in Decimal Units

Modeling for the field and/or layout demands more precision than your standard visualization model. If you’re based in the US, this is especially important. In Revit, for example, the units may be set to show up to 1/16 or 1/8 inches of precision. This means any dimension less than 1/8 of an inch will simply
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How to Section a Point Cloud for Clash Detection

Viewpoints are the means to effective clash detection inside Navisworks for use with point clouds or otherwise. Saving viewpoints with section planes or boxes lets us better isolate areas of the building and more importantly, digest point cloud data clashing against model geometry.


How to Clash Scan Data

Autodesk Navisworks was mentioned in a previous post as our primary clash detection tool. Aside from simply bringing in the point cloud and visually confirming the models match, we can also use the Clash Detective window within Navisworks to coordinate what’s been built versus what’s about to be installed with significantly more intelligence than a
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Using Point Clouds in Clash Detection

We use Autodesk Navisworks almost exclusively as our primary clash detection tool. However, up until about a year ago, we have only worked with “projected” models – that is, shop drawings in 3D format that convey what the project will look like once that particular system is installed. Combining all of these files into Navisworks
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Six BIM Point Cloud Formats You Should Know About

Scanning a space and bringing it into a program like Leica Cyclone will let you further manipulate the scans and, most importantly, stitch them together into a single cloud, which can then be exported as a standalone file. But what type of file do you need, and what do you do with it after it’s exported? There’s
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Three Easy Steps to Bring Reality to BIM with Scanning

Before diving into point cloud formats and how to use them, it’s worth starting with an overview of how scanning works. Our experience primarily lies with Leica Geosystems products, but the same procedures also apply to other modern laser scanners.


An Essential Tool for a Standout BIM

High Definition Surveying (HDS) is not a new technology. It has long been applied in many other industries for applications such as crime scene investigation, car crash analysis, historical documentation and clash detection. However, it has recently begun taking off in the AEC industry, and we’re seeing a lot more activity from almost all stakeholders,
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Hands on with Leica 3D Disto

Last week we used the Leica 3D Disto in the field for the first time. A local project that involved steel erection made for a great first test case. The goal was simple: determine the deviation in a bent plate to ensure it meets the construction tolerance off the column grid.


How to Go Mobile with Point Clouds

Importing point clouds to a laptop or desktop machine is easy. Whether you’re stitching scans together or just viewing them, there are a number of programs available to handle the data. Leica Cyclone and Autodesk ReCap are just a couple of examples. However, bringing that point cloud data with you into the field on a mobile
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Where Did That Model Originate?

Much like layout, BIM has to have some sort of control – something to reference in order to orient yourself and your content. Every BIM file, whether CAD-based or otherwise, has an origin point. The trick on any project involving multiple design parties and subcontractors, is agreeing on where to line up models.


The Top Five BIM File Formats & How To Use Them

Everyone has seen an email hit their inbox with attachments in file formats they’ve never heard of. While I can’t promise to explain the non-BIM formats, I would like to review a couple common formats we see pretty often in the BIM world. Here are the top five BIM file formats we see the most
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A New Tool for BIM: The 3D Disto

Beginning this week, we’re digging into a new tool (to us) from Leica Geosystems called 3D Disto. With some basic orientation, you are able to shoot points much the same way you would use a total station, only you’re not looking through a scope but using the screen on a tablet. Thanks to the built-in camera,
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Three Easy Ways to Check Spot Coordinates

Whether you’re using the model for layout or just checking to ensure the slab you just drew is truly at 0′-0”, spot coordinates are useful for quick location information. Specifically, sometimes you need the Y, X, and Z (or Northing, Easting, Elevation) of a specific point, and standard linear dimensions won’t cut it. Here’s how to
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Four Things You Should Know When Buying BIM Hardware

There’s a lot out there on software, but the computers running all that software are just as crucial to the success of any BIM group. As you might expect, BIM is very processor and memory hungry.


‘Heat Mapping’ Irregular Floors

Many of our interior build-out projects are in existing spaces, and these spaces often have their fair share of challenges. One recent challenge included an irregular concrete deck with low spots, coined “bird baths.” At the end of the day, this floor had to be leveled.


How BIM 360 Glue Changes Model Use

Many years ago, we decided Autodesk Navisworks would be our “decoder ring” by which we’d assemble all the different models we work with from start to finish. At a minimum this means subcontractor models, but it also usually includes design models from architects and engineers. Mobile model use, particularly in the field, has never been practical
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Key Tools for Preconstruction Support

At Holder, every project passes through the preconstruction phase in order to provide value analysis, balance the budget, and procure subcontractors. BIM can have a big impact at this stage of a project before we even set foot on site.


Beyond 3D: The Many Dimensions of BIM

When construction professionals think about BIM, they often think about it in terms of moving from 2D to 3D. However, it doesn’t end there. Linking a project schedule to a 3D model gives you what’s called a 4D sequencing model, which is often used to produce 4D sequencing animations. These are an excellent way to
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What Does BIM Mean to the Construction Industry?

Building information modeling is a problem-solving tool that communicates a plan to construct buildings more effectively. A common misconception is that BIM has to be a 3D, 4D, or 5D model. However, BIM can be as simple as a logistics plan or as complex as a facilities management model.


University Development of Prototypes for Planar Construction Prefabrication

At the HxGN LIVE 2013 conference in Las Vegas, one of the presentations focused on work done by a pair of like-minded programs from Auburn University who set out to improve the messy, inefficient process of drywall installation using laser scanning and a new tool, the 3D Disto.


Swedish Parliament: 5,000 HDS Scans for BIM

HxGN LIVE 2013 featured an awesome class on a massive laser scanning effort. The Swedish Parliament evidently required a complete laser scan of their site, including a network of underground tunnels. There’s a huge remodeling/renovation need over the next several years and scanning the area is a smart and efficient move in my opinion.


2013 Hexagon Highlights as a Contractor

I’m back from HxGN Live 2013 in Las Vegas with lots of photos, notes, and business cards. The whole thing was fantastic and it happened in a blur. One of the first things that struck me was how large the conference was. The keynotes were probably the best indicator – people on all sides of
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A Leading EPC’s Experience Using HDS Services on Multiple Projects

One of the first presentations I attended at HxGN LIVE 2013 was from Tellepsen – a Houston-based contractor that’s partnered with a local scanning company called Truth. They shared lots of great examples, but the one that hit home was their use of point clouds and Navisworks.