Balfour Beatty Transforms Historic Texas Middle School
Stephen F. Austin Middle School is a historic and much beloved institution in the Texas community. The school was in dire need of a construction partner that could transform it into a structure that is built to last. And with the passage of a $132 million bond package in 2015, Bryan Independent School District retained Balfour Beatty to accomplish just that.
Considered state-of-the-art when it was originally constructed in 1937 as a high school, Stephen F. Austin Middle School had since become obsolete in terms of classroom size, safety and practicality—despite multiple renovations over its lifespan. Nearly one quarter of the school’s classrooms were smaller than state guidelines. There was no hot water in the boys’ locker room. Bryan Independent School District entrusted Balfour Beatty to construct a future-ready facility while preserving a piece of civic history. The innovative rebuild, which converted the existing three-building school into district administrative space, included the addition of a new, three-story facility that encircles its predecessor. By any standards, this was no run-of-the-mill construction project.
The “Known Unknowns”
From the beginning, the team knew they’d contend with the conventional challenges that accompany renovating aging structures—building off of incomplete or inaccurate as-builts, abating hazardous materials and meeting code to name a few. These were the project’s “known unknowns.” For example, once the plaster had been successfully removed from the walls of the former school’s auditorium, the project team discovered that the existing, original studs were not fire treated wood. This was not surprising, but it required the team to absorb an additional three weeks of labor into an already compressed eight-week summer schedule. Over the same months, the presence of asbestos was detected, and work in the area was brought to a halt until it was thoroughly remediated. But those wouldn’t be the only relatively routine issues the building team encountered. They were aware that the auditorium’s roof drain was leaking, but after repairing a corroded pipe only to observe the seepage persist, the team determined that a replacement of the entire line was in order.
“You know you’ll be dealing with normal wear and tear and maintenance issues, but you never know the cumulative effect they’ll have on your budget, scope and schedule until you get the walls open,” remarked Lee Gibson, senior project manager.
The “Unknown Unknowns”
The “known unknowns” were certainly impactful findings, but of far greater magnitude to the project were the unpredictable conditions that transformed this project into an excavation of the “unknown unknowns.” Since the new school was designed to wrap around the three buildings that encompassed the former Stephen F. Austin Middle School, the project team was mindful that the process of tying into structures that possessed diverse foundation systems would be challenging.
But what they couldn’t possibly anticipate is that the existing buildings had been constructed with extreme variances in their floor elevations—a condition revealed after the design had been finalized using a laser scanning drone. In some locations, the deviations were as diminutive as a few inches, and in other locations, as drastic as four feet. These elevation discrepancies didn’t just span one end of a building to the other. Oftentimes, single rooms were sloping, requiring extensive leveling efforts. But more importantly, they rendered the initial design completely unviable, as the new school’s structural steel would have abutted too close—a mere two inches—against the walls of the existing auditorium.
Balfour Beatty incorporated the scanned points into a 3D model to create the most precise representation of existing conditions. With the knowledge derived from these scans, Balfour Beatty collaborated with PBK Architects to rotate the new facility such that it would fit around the existing buildings—a feat accomplished by shifting three column lines approximately one to two-and-a-half inches either east or west. By resolving these conflicts before construction progressed, Balfour Beatty saved the school district hundreds of thousands of dollars that would have been incurred through the processes of refabricating steel, moving piers and other ancillary work—all while preventing potential schedule overruns.
Building Information Modeling (BIM) helped bring additional “unknown unknowns” to light. The process, which received enthusiastic subcontractor buy-in, guided the team to unearth and resolve approximately 35,000 conflicts, including 11,000 clashes within the overhead ductwork and electrical racks. BIM has been an invaluable tool, enabling Balfour Beatty to prevent time-consuming and potentially costly errors in the field and empowering specialty contractors to prefabricate materials.
At Balfour Beatty, we assemble extraordinary teams for whom no obstacle is an impediment to success. Because when you couple highly capable and creative people with industry-leading technology, the end result is always a structure that will stand the test of time.