Callbacks Are a Pain. Technology, Proper Procedures Help Minimize Mistakes
Glazing is a tough job. Glaziers deal with various challenges, from learning how to deal with many suppliers and parts to coping with different job conditions. However, technology has helped alleviate some of the burden, which, in turn, has reduced the
number of errors leading to callbacks. This is especially true for projects that require glass
railings.
While uncommon, callbacks still occur despite the many systems that counter human
error. Reasons for callbacks range from trade damages to measurement miscalculations to
changing conditions.
Andy Russo, vice president of engineering and business development at Wixom, Mich.-
based Glass + Metal Craft (GMC), says call-backs are extremely annoying, adding extra
time and expenses.
He explains that callbacks can result from changes throughout the project, especially
for projects that require glass railings around stairs. If a glazier takes measurements early in the process and changes are still being made to the structure, the conditions will fluctuate, impacting the final product.
“Your measurement starting and ending points may change,” he says. “Often, we install a stairway, and when we get out there, the conditions don’t match what was in the
drawings and measurements. Along the way, someone added a plate, straightened something out, or changed the structure itself.”
Russo says that glass railings around stairs are complex. That’s because a staircase is a
three-dimensional (3D) environment with a downward slope that could even feature
curves. As such, it’s difficult for glaziers to measure properly. This contrasts with glass
façade installations, which are mostly a height and width type of environment, says Russo.
Michael Mims, project manager and safety director for San Diego-based Long Glazing
and Doors (LGD), adds glass railings usually have tight clearances, particularly at handrails, adding to the complexity. Angles must be precise, or a 1/16th of an inch will “stand out like a sore thumb.” Coordination between trades enhances the difficulties, he adds.
Additionally, Russo says the rigidity and lack of flexibility of glass railings often make
installation difficult for glaziers.
“The stringers and mounting plates are mild steel, so those are fairly rigid,” he says.
“The connection points are definitely rigid. You’re talking about posts, railing systems,
and, in many cases, the glass. So, there’s not as much tolerance or flexibility in the loading.
What tends to happen is that if one measurement is off, the entire thing is off.”
To minimize measurement errors and reduce callbacks, glazing companies use various methods and cultivate a culture of responsibility. Jason Wroblewski, executive vice
president of Dallas-based Haley-Greer Inc., says glazing companies can reduce callbacks
via proper training, planning, experience, leadership and culture. Mims says LGD adopted several quality management practices, leading to the company becoming the first
glazing company in San Diego to earn the North American Contractor Certification.
“We hold ourselves to a higher standard than most,” says Mims. “Rigorous quality management processes leading up to the installation and verification procedures upon completion are how we mitigate punch list deficiencies.”
Technology also helps reduce callbacks, including using laser measuring systems and software. LGD uses Logikal computer-aided design (CAD) software to generate parts lists and take-offs. The software also interfaces with a digital miter Tigersaw. Mims says each part that is processed through the saw comes with a barcode for labeling/tracking.
He adds LCD recently hosted a meeting with Hilti to introduce a new product and process for safety barrier glazing and glass railings. The product is the Hilti-HY 270 mortar, which
is resistant to dripping during stair installations and does not bond to the glass or metal shoe.
GMC uses a process called “Assured Fitment.” Russo says project engineers use laser-based technology to assess dimensions in 3D. The technology has an accuracy of 1/16 of
an inch over 33 feet. The measurement data is inserted onsite directly into the CAD for the architectural system.
Russo says the process has cut the measurement process from three days to half a day, project-dependent.
“It took as long as three days to measure a stair project,” he says. “The process used to include interpreting hand-written notes, and someone had to load those into a drawing file. It could be a couple of weeks. We can now measure in half a day. That’s getting out there, setting up and doing the measurements. We can narrow it down to a few hours for a one-floor project. The data is dumped into a file, so there is no interpretation. We save that whole second week.”
Russo says since they started using the “Assured Fitment” process, the number of callbacks has been reduced to nearly zero.
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