In the past, architects faced the daunting task of measuring historic buildings using traditional tools like plumb bobs, strings, rulers, and pencils. This method was not only time-consuming but also prone to errors. Today, a groundbreaking technology has revolutionized this process, saving time and money while delivering unparalleled accuracy and detail: laser scanning.
Understanding Laser Scanning
Laser scanning technology made its debut in the early 2000s, offering a relatively simple yet incredibly effective solution. It involves a laser projecting a beam of light onto a surface, measuring the time it takes for the light to bounce back, and creating a data point. When millions or even billions of these measurements are combined, they generate a 3D model of a structure. Modern laser scans can capture data points at five-millimeter intervals.
One challenge with laser scanning was the overwhelming volume of data it produced, often reaching terabytes, which could be burdensome for both users and their computer systems.
Real-World Success Stories
In 2015, Wichita State University tasked WDM Architects with converting five interconnected factory buildings into classrooms and learning labs in less than two years. With different roof heights and truss configurations in each building and no existing blueprints, the project seemed like a daunting challenge. To tackle this, we turned to laser scanning.
The laser scan generated a massive point cloud, which Jason Harlan at WDM transformed into a usable model in Building Information Modeling (BIM). The investment in laser scanning paid off because we had zero conflicts during construction based on having it laser scanned.
The advent of scan-to-BIM technology marked a significant leap in the effectiveness and worth of laser scanning. It enabled the seamless transformation of data collection into a readily applicable format, complete with precise measurements. This resulted in the creation of a digital twin, empowering architects to design new spaces for fresh purposes in historic buildings.
In 2021, WDM Architects partnered with Contemporary OB/Gyn in Kearney, Nebraska, for a renovation of their current medical office, a vacated historic Catholic church that had been turned into office spaces. We once again leveraged laser scanning, and this time, the point cloud was rapidly converted into BIM files, saving both time and money.
Why Choose Laser Scanning?
Many historic buildings lack architectural drawings, and even if they do exist, they offer limited, two-dimensional information. Without accurate documentation, the risk of irreparable loss in case of damage or destruction looms large.
Laser scanning is a non-destructive method for evaluating historic buildings, aligning with a ‘do no harm’ philosophy of minimal intervention, as advocated by experts such as Susan Macdonald of the Getty Conservation Institute. For instance, laser scanning aids in preserving fragile historical artifacts like a 17th-century paper-mache ceiling.
In the present day, a solo operator armed with a compact 12-pound scanner, designed to fit snugly within a backpack, can capture data of up to 2 million points per second. With a range of 130 meters, the scanner efficiently captures vibrant 3D point clouds in less than two minutes. Furthermore, an intuitive App interface allows the user to effortlessly tag measurements, videos, images, text, or voice files directly onto the point cloud. The result? Laser scanning eliminates the necessity for field verification and site revisits, streamlining the entire process.
Moreover, laser scanning provides unparalleled accuracy and detail, enabling preservationists to recreate physical features with a level of precision previously unattainable.