Excavating the Folger's Future | A Renovation Progress Update
From lifting marble slabs weighing thousands of pounds to digging out the excavation site, the Folger renovation is well underway—and laying the groundwork for its next steps, too. Reaching out to a wide range of visitors, the building renovation project will add new galleries, an education lab, research spaces, social gathering spots, and much more.
After years of planning, dreaming, and discussion, the Folger building's renovation project is moving visibly forward. Over the winter of 2020 and spring of 2021, the Gilbane Building Company, working with a variety of specialized subcontractors, has almost entirely transformed the Folger landscape. This stage of the work included many steps, but its goal is simple: to begin opening up the area below street level where new public spaces will eventually be added, after which the beautiful Folger lawn will be restored above them.
A wide excavation site now stretches from the Folger's distinctive northern façade toward the sidewalk along East Capitol Street SE—and extends partway back along the building's east and west walls, too. At the end of April 2021, the site was about six feet below street level; that required digging down a full nine feet next to the building, because of the raised terrace beside it. Eventually, much of this area will be about 11 feet below street level; the deepest section will be about 25 feet down.
The digging has also uncovered a part of the building that is crucial for the renovation: the Folger's long-buried northern foundation wall, which has not been exposed to the light of day since the building was constructed almost 90 years ago. After a series of carefully engineered steps, this once-hidden wall—located directly below the northern façade—will be permanently opened up, making it possible for visitors to move between the new spaces and the original building.
For all of the changes that are underway, however, the renovation will keep the original street-level appearance of the building as the architect Paul Cret envisioned it. "I love historic features," says Dustin Humbert, Folger director of operations, who works closely with the Gilbane team and others on the project. "The renovation project is still allowing the original artist to have their impact on the world. Meanwhile, this is adding still more spaces for everyone to enjoy, which was the original founding principle of the Folgers. They amassed this collection, and their ultimate goal was to give it back to the world, so the world could enjoy it."
Moving the Stonework
In order to excavate the site, the team first took on a major task. Paul Cret had filled the area in front of the building's façade with a wealth of white marble elements, from multiple staircases to benches, large planters, a wall along the front face of the terrace, and numerous pavers, as well as some contrasting bluestone pavers. The effect is a magnificent part of the Folger's appearance, but it also meant that hundreds of stone pieces had to be removed—a challenging process due to their surprising fragility and significant weight. The smallest and lightest of the marble pieces weigh about 100 to 200 pounds; the heavy pieces that make up the planters weigh several thousand pounds each. The stone masons of Lorton Stone moved them all.
The Folger asked Architectural Conservator Amanda Edwards of MFTA Design + Preservation—who previously worked on the firm's award-winning treatment of the building's white marble exterior—to assess the condition of the stones ahead of time. Edwards, who grew up nearby and has long enjoyed participating in Folger events, says she was drawn to architectural conservation because "it's the study of how buildings change," she says. "To be able to keep the building and all of that original intent, and watch it change to meet modern needs, is very exciting."
When it is time to restore the lawn, the terrace, and the stonework, the team plans to keep the original marble for the staircases, the big planters, and the terrace wall, including the coping stones along its upper edge. Some of the stair treads with minor erosion may simply be reversed, in a strategy that Edwards suggested. That way the damage will be hidden, while still using the original marble. As for the overall look of the building and lawn, "the easiest way to think of it is this," says Ruth Taylor Kidd, the Folger chief financial officer. "If you're standing on East Capitol Street looking at the building, every vertical surface that you see will be the original material."
"If you're standing on East Capitol Street looking at the building, every vertical surface that you see will be the original material."
— Ruth Taylor Kidd, chief financial officer
Most of the marble elements were removed like any other large stone pieces. But when it came to the huge planters, all bets were off. "I'm a neighbor," says Folger Director Michael Witmore, "and during the pandemic, I regularly came by to walk the site. Seeing the planters come off is one of the most vivid memories from that time. The excavation had already begun, but that brought home the magnitude of the task ahead. The planter stones were precious, very heavy, and integral to the whole program of the building. It felt like we had really crossed the starting line."
"The planter stones were the biggest stones," says Jeff Busch, the Gilbane senior general superintendent who is managing the work. "The hardest part was getting them free to move." The equipment used to hoist the other stones with straps was not powerful enough to lift them, so the team replaced it with an excavator with the bucket removed. "The planter stones were tucked in underneath and next to façade stones that were staying," Busch says. The crew cut the joints and the mortar under the stones, and "they had to use prybars and walk the stones out by hand, with a strap to put a little tension on it." To add to the delicate nature of the work, each planter includes a panel with a work of art—an Art Deco carving of the winged horse Pegasus, who in Greek mythology released the waters of the Hippocrene fountain, source of poetic inspiration.
The effort to remove the pieces of the four planters took three weeks. "The real trick is, when they built these buildings back in the day, they never intended for them to be taken apart," says Busch. "The way everything was built, it was very sequentially stacked and interlocked, and the joint tolerances were about an eighth of an inch. So if you think of several thousand pounds of marble and you're trying to pull it straight out, saving pieces on both the left and the right and above, and you've literally got an eighth-inch tolerance to work with—you really start to appreciate how good these guys are at what they do."
At about the same time that the first, smaller marble stones were being removed, the excavation itself began, but with a step that takes place before digging gets underway. To anchor and delineate the wall of the future excavation site, an auger was used to drill a row of deep vertical holes, in which 50-foot-long pipes were buried as vertical piles. Once the digging started, the excavator operators would trace a straight line precisely against the standing pipes.
As the depth of the site increased, workers would use metal threaded rods welded to the piles to attach heavy wood lagging boards to them, shoring up the side of the excavation. At a depth dictated by the engineer, tieback cables were drilled into the ground at an angle and grouted in place. The tiebacks were anchored to the vertical shoring, providing the support to excavate deeper.
"What makes this excavation interesting," says Busch, "is that it's very long and narrow, and the access for it is pretty difficult. A typical excavation will dig a ramp down into the hole and back the trucks down to load them. We didn't have room to do that because we had to leave a large berm against the foundation wall with about a six or eight foot wide platform at the top, for work on the façade for the duration of the excavation." Instead, the team placed one excavator in the site, and used a small Bobcat to remove and pile up the soil it dug up.
Another excavator was stationed outside the area next to the Folger's west wall, where it loaded the soil into a series of dump trucks that took multiple runs. "The lead operator who was up there loading the trucks was very experienced," says Busch. "He's the foreman for their crew and it's a huge responsibility to be operating that equipment. The bulk of the responsibility lands on the operator to make sure that they're keeping everybody clear of the equipment and trucks." On the busiest days, the team moved as many as 40 truckloads.
A New Opening
As the renovation continues, workers marked a small milestone as they cut out the very first, very modest opening in the Folger's northern foundation wall. Using a carbide-tipped wire inserted through a drilled hole, they cut an eight-foot-by-eight-foot opening—about the size of a one-car garage door.
During the same time that crews have been removing stones and excavating the outdoor site, other crews were at work just inside the northern foundation wall on the underground floor known as Deck A, literally walled off from them. With this opening, a Bobcat can empty the rubble and debris from the interior work, and workers can easily move between the indoor and outdoor areas.
While the new opening is just one small part of the renovation work, like much of the project it is also powerfully affecting and even inspiring, as the renovation steadily moves toward its goal of providing new public spaces.
"Today I walked through the new door in the north foundation wall," Witmore wrote on May 11, 2021. "And thought: daylight! In a project like this one, you spend a lot of time planning, consulting, and waiting. But when I saw the bold shock of sun shining in on the interior of Deck A, it felt like our project was literally and figuratively opening a door, letting light in, but also allowing us to move out into the world."
"You can’t imagine how odd it is to pass through a nearly two-foot-thick foundation wall into the once dirt-filled space below the terrace. It was something that was hard to even imagine years ago, but now it was as simple as passing through a door. What was inside now becomes outside and vice versa. What a great metaphor for an institution that is becoming more porous, more connected to the world outside."
Esther Ferington is an editor, writer, and content developer based in Alexandria, Virginia.
Lead photo by Lloyd Wolf