Building Surveying, Laser Scanning and BIM

They say the shortest distance between two points is a straight line. Well then my journey to this point in time certainly has not been the shortest. I began my journey as a building surveyor while at my first job working for an architect. I remember being tasked with measuring a building to create an as-built architectural floor plan. The tools of my trade at that time were nothing more than a clip board, a piece of paper, a pen and a twenty-five foot steel tape measure. I was sent out with no training on the means or best methods to use to accurately capture and document the existing conditions. I remember thinking, there has to be a better way.

Well twenty-six years have since passed and my passion to find a better way to document buildings has only grown. So have the means and methods to do so. The tools of the trade today include various instruments capable of capturing complex imagery and measurements in 3D. Perhaps one of the most significant advancements is HDS (High Definition Survey) 3D Laser Scanning. A laser scanner is a high-end laser measuring device capable of capturing hundreds of thousands of points per second, each having an X, Y and Z value. The resulting points form what is referred to as a point cloud. The point cloud can then be processed to produce either 2D or 3D deliverables.

2D documentation typically takes on the form of floor plans, reflected ceiling plans, roof plans, exterior elevations, building sections, etc. and is often created using programs such as Autodesks AutoCAD. More recently weve been seeing a transition towards 3D documentation such as 3D AutoCAD and Building Information Modeling (BIM) authoring tools like Revit, Bentley and Archicad. Unlike 3D AutoCAD which represents geometry in 3D, BIM authoring tools also add intelligence that can be used to perform complex analysis. BIM tools can be thought of as a graphical database. In addition to 2D drawings or 3D models, other means of documentation can include photo imagery such as Quicktime spherical .jpgs or Leicas measurable TruView imagery which is derived from laser scanned point cloud data.

As the means and methods for building survey have evolved I have seen various stakeholders entering the marketplace to provide as-built documentation services. These have included stakeholders such as architects, engineers, technicians, and land surveyors. Unlike the profession of land survey, there are no licensure or certification requirements to perform building survey in the United States. As a result we currently have a wild west of sorts of various service providers.

This then begs the question who is more qualified to perform a building survey? Architects and engineers are typically experts in buildings and building systems, yet not necessarily measuring. Land surveyors are typically expert in measuring, but buildings and building systems often fall outside their domain of expertise. So how then is an Owner to determine who is best qualified to provide as-built services?

Regardless of the service provider or the means and methods used, one thing is certain; our industry is experiencing a transition from a 2D world to a 3D world. At the center of this are technologies such as HDS laser Scanning and BIM. The demand for higher level data and the advent of technologies such as HDS laser scanning are bringing together numerous players within the marketplace to provide these services. In the coming weeks I hope to bring you insights and an in-depth look into new advancements relating to how these technologies and issues are shaping the world of building survey.