A company called Vertical Access goes to extremes for a close-up view of history.

Story from the archives by Tricia Vita / Aug. 12, 2005

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Vertical Access scales New York City's St. Bartholomew's Church. (New York Landmarks Conservancy)

Manhattan's St. Thomas Church, a magnificent 1913 Gothic cathedral, has a nave vault nearly 100 feet above Fifth Avenue.

"There's no way anyone from the ground can appreciate the level of craftsmanship and detail that's gone into this," says Kent Diebolt, who dangled from a rope to inspect the church's carved stone altar screen and Guastavino tile ceiling.

"We go to extremes" is the motto of Vertical Access, Diebolt's Ithaca, N.Y.-based company. Its technicians use rock-climbing gear to rappel down skyscrapers and scale steeples, documenting structural conditions for architects, engineers, and conservators.

Vertical Access crews have summitted the stainless-steel-clad spire of the Chrysler Building, where they helped pinpoint the locations of water infiltration in 1999.

Last December, they climbed atop Philadelphia City Hall and into Alexander Milne Calder's 30-foot-tall bronze sculptures. "We had to remove the access panels and crawled inside to examine the condition," Diebolt says. "We used the See-Snake to look way down inside the leg. You couldn't get within six or eight feet of it. You couldn't get your arm down to touch it." The "See-Snake," a fiber-optic diagnostic tool, consists of a miniature video camera with wide-angle lens, built-in light source and radio transmitter. For the contractors gathered around a monitor in another part of City Hall, the live video feed provided by Vertical Access was the next best thing to being there.

"Sometimes it's hard to move projects ahead because the client isn't sold on the fact that the work needs to be done. They don't see a problem yet," says Diebolt, recalling a situation where a proposal languished until a piece of the facade came crashing down. "But it's hard to argue when you're seeing [the problem] right there in real time."

The hanging flume (Ron Anthony)

In April, Diebolt's crew, along with two engineers from New York-based Robert Silman Associates, journeyed to western Colorado to document the remnants of a 13-mile-long hydraulic-mining flume pinned against a 400-foot cliff above the Dolores River.

"We had to get someone who could get to the more difficult access points and would also be able to communicate with material scientists," says project manager and wood scientist Ron Anthony, of Anthony & Associates, in Fort Collins, Colo. A $111,696 grant from the Colorado Historical Fund and matching funds support the research team, which also includes archaeologists, historians, a geologist and a master planner.

Built in the 1880s, the deteriorating wooden flume landed on Colorado Preservation's annual list of the state's most endangered places in 1999, sparking an effort to preserve and use the National Register-listed site as a heritage tourism destination.

"Part of Kent's role was to give me some insight into what he observed may have been the most feasible construction method," says Anthony, who wants to reconstruct a portion of the deteriorating flume using historic methods.

According to local lore, miners suspended from above built the hanging flume; the archaeologists' discovery of a bosun's chair (a seat made from a plank and a rope, used for working aloft) lends credence to that theory. How did those workers perform the physically challenging tasks of drilling thousands of holes and inserting 18-inch metal rods into the rock? After spending several days on the cliff wall, Diebolt believes they used what's called a star drill, slowly pulverizing their way into the rock. How did they lower 200-pound wooden beams and maneuver them into place to support the weight of running water? "This is a pretty robust structure. I think they probably had a cart with materials on it, with a little gantry and a boom, so they could lift things on it."

The sight of climbers dangling over the flume drew onlookers, but Diebolt, whose work in the concrete canyons of Manhattan often causes New Yorkers to look up in amazement, plays down the high-thrill aspect of his job. Industrial rope-access technicians use both a working line and a fall-protection line for safety, he explains, with several devices to ensure that they won't slip down the rope.

On the Chrysler Building, 1999 (Vertical Access)

Even so, the job requires a unique combination of skills. Vertical Access runs training sessions on a climbing wall at Cornell University that is equipped with simulated window openings and roof parapets. "We've trained architects and engineers to do the climbing, and we've trained climbers and taught them how to do the inspections," Diebolt says. "Both work."

After a two-day training session with Vertical Access, Justin Spivey, a senior engineer at Robert Silman Associates, braved Colorado's hanging flume as well as the 80-foot-tall roof tresses of the New York State Capitol. "The scariest part is the descent," says Spivey, who compares the experience to walking slowly backward over the edge of a cliff. "But once you're situated on the part of the building you're interested in, and you've got your clipboard and measuring tape in hand, then it's about the work."

Spivey, whose specialty is historic structures, enjoys the collaborative nature of these jobs. "The longer we work with Vertical Access, the more we learn from each other," he says.

Last year, when cracks were discovered in the radial spokes of a rose window measuring 30 feet in diameter in St. Bartholomew's Church, designed by Bertram Goodhue in 1917, the New York Landmarks Conservancy enlisted Vertical Access's help.

"We put a tiny cut in the glass, then ran a stainless-steel strap around that, and tightened it up like a big bore clamp," says Diebolt, who worked with Silman Associates' engineer Timothy Lynch to devise the temporary fix. "Repairing a window like that could cost a million dollars. This cost a only a few thousand, but it could be good for 20 years."

In the world of high-altitude preservation, Vertical Access has few peers. "Remember that wonderful movie Ghostbusters? Who are you going to call?" says Roger Lang, the Conservancy's director of community programs and services. "Kent's who you call when you've got something that's high up, or hard to reach, or out of sight. We've turned to Vertical Access on a number of occasions, and they've saved our bacon every time."

Tricia Vita is a journalist who divides her time between New York and an 1850s mill conversion in Norwich, Conn.

This story was originally published on Preservation Online on Aug. 6, 2004.

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