Where Ladders Cannot Reach: Drone Technology and Historic Restoration

Modern technology saves time and money, and gives designers a unique view of the Iowa State Capitol Building.

The Iowa State Capitol, constructed from 1873 to 1884, has been a source of great pride for generations of Iowans. Over the last century, windows on the north and south wings of the building began to show signs of weakening and deterioration, and in 2001, RDG was contracted to take the lead on a series of major restoration projects. During RDG’s original investigation more than 20 years ago, invasive and expensive tower cranes had to be brought on-site for a full week to provide architects with a face-to-face view of the building; in the spring of 2017, when RDG returned with drone technology to reanalyze exterior conditions, the same level of investigation was completed in a just few hours.

Piloted by RDG employees (each of whom are licensed by the Federal Aviation Administration to operate commercial drones for business purposes), the drones conducted an intensive investigation of the exterior walls and windows of both the Iowa State Capitol Building and the Ola Babcock Miller Building (formerly the Old Historical Building), the two oldest buildings on the State Capitol complex campus.

As they hovered just a few feet away from the buildings the drones captured extensive video footage of the surfaces and sent it back to pilots instantaneous (thankfully, after concluding the drones were too small for a meal, the resident peregrine falcon even allowed us to continue). Once all the necessary data was gathered, architects analyzed the captured footage to accurately document the buildings’ existing conditions and develop an action plan for repairing and maintaining windows, stone and roofing. The digital files were also delivered to the building owners for record-keeping and to provide comparisons for future design and repair.

Thanks to drone technology, RDG’s team of designers was able to conduct a complete building investigation in far less time and with far fewer risks than they could two decades ago. The resulting design focuses on rehabilitating, repairing and replacing window structures to restore the integrity of the historic Iowa State Capitol Building.