Downtown Glacier: Old Building, New Vision

Brad Hinthorne, managing principal for Perkins&Will, describes the ‘70s vintage design as “precast concrete with strip windows, kind of a V shape, [and a] blank wall facing the parking lot.” Not very attractive for new tenants.

“We are trying to make this into an iconic signature class-A office building,” says Chang, “and I think the architecture, the shape, and also the orientation really speaks to that.” As the owner, Chang had to decide how much of the old building to keep and how much to scrap.

Hinthorne explains, “They look at the pros and cons of their asset and they say, ‘What if we left the skin the way it is and only did some repairs?’ and ‘What if we completely re-did it? If we re-did it, can we also add square footage? Or can we not?’… And also how does it compare to the cost of starting over, rebuilding new?”

The decision is based largely on the condition of the existing structure, but that analysis was complicated by a lack of detail. Mike Fierro, associate principal with Reid Middleton and the structural engineer of record on 601 W. Fifth, found only nine sheets of structural blueprints from the original construction, compared to forty-five sheets for the renovation. “When we’re going back and renovating those old buildings,” Fierro says, “it’s always difficult to figure out ‘Why did they do this?’ or ‘How would they do that?’”

The architect’s job is to walk the client through the options. Hinthorne says, “If you added it all up and looked at the price tag of doing all of those things, it’s less expensive than doing new and probably more valuable, at the end of the day, than just putting some Band-Aids on it.” Most clients would’ve done the bare minimum, Hinthorne believes, but Chang was convinced that a new skin on old bones would solve several problems at once for about the same cost.

“It’s a tough leap, right, to go from ‘Do we just renovate the building?’ to entirely new skin, new vision, new image, and a new presence,” Hinthorne says, adding, “Good for them.”

Seismic Shift

Some no-brainers had to be fixed anyway. The building’s water service, for example, required a secondary line for firefighting, which had to be installed under F Street, according to LaQuita Chmielowski, senior land use planning manager with DOWL Engineering. Chmielowski says DOWL was brought in to 601 W. Fifth early on because of land use planning, entitlements, and rights-of-way issues. The bulk of civil engineering, she says, involved coordinating between the state right of way on Fifth Avenue and the municipal right of way on F Street.

The renovation also allows for asbestos abatement, says Neil Bhargava, senior project manager for Neeser Construction. The general contractor started demolition in July 2020, chipping concrete panels off the steel columns. By November 2020, almost nothing was left but a framework of girders, slab floors, and the solid concrete wall on the west side that the entire structure ties into.

To be clear, plans for renovation predated the 2018 earthquake. Engineers from Reid Middleton had been sketching options for building add-ons since May of that year. “The engineer they were talking to at the time said they should probably tear it down and start over, which in hindsight isn’t a bad idea,” Fierro says with a laugh.

The initial analysis concluded that a seismic upgrade was not necessary but would be a good idea. After the quake, though, it became essential. “The north tower was damaged,” Fierro says. “I went out and said, ‘Yeah, this shouldn’t be opened to the public.’”

Where the concrete cracked, some temporary strengthening was added, but Fierro says a full upgrade would have been too expensive. Therefore, he came up with what he calls a “clever approach” that had been tried on a previous building: steel bracing that pulls the structural load away from the west wall.

Hinthorne says, “In this case it was the perfect storm of, you know, there was some seismic improvements that were needed… the ability to add more square footage, the ability to make it a more high-performing building.” And it all worked out for the best.

Angling Up

The new addition fills in the middle of the “L,” increasing the floor area from 8,000 square feet at ground level to roughly 11,000 square feet per floor, Chang explains. Consequently, the upper floors cantilever over the plaza below.

Fierro never worked on a nine-story building before, but he was involved in the expansion of the Consortium Library at UAA, where the third floor extends beyond the foundation (and where multi-story windows reveal the structural crossbeams).

The building shape is also a new one for Kirk Malanchuk, the project architect for Perkins&Will. “Structurally, it has garnered its own amount of attention from the engineering community,” he says, “which I think is somewhat representative of the challenge of it.”

One huge challenge is that the foundation was not designed to hold a cantilever, like a diving board nine stories high. Thus, Neeser had to install a new foundation—with the building still on top of the old one.

“The underpinning we did,” Bhargava explains, “by drilling the holes in the concrete to support the existing footings, and then we dug the dirt below the concrete and then put the rebar and poured the concrete. So that was a tricky job.”

The beefed-up foundation takes the load from two angled columns that define the triangular face of the “prow.” But not directly—the design has an additional complication.

For a more inviting entrance from Fifth Avenue, the south leg of the “prow” splits just below the second floor, transferring its load to two smaller columns, both more horizontal than vertical. Indeed, one of them is not designed to hold any weight from above; Fierro says it’s only there for “wind girt” to resist lateral stresses.

The other, shorter angled column does hold weight—up to 1.2 million pounds, Fierro says—but it’s in a more precarious position, parallel to a busy street. “If something happened to that column—if a drunk driver was able to get there and impact it—it could’ve potentially caused some collapse to the addition,” Fierro says, explaining why he calls that crucial piece of steel “The Jenga Column.”

“So I designed the building with the column and without it,” Fierro says. “What I did was, I asked, begged, pleaded with the architects if I could put in something called belt trusses.”

Essentially, additional cross-braces around the second, third, and fourth floors create a box that can do the Jenga Column’s work, in a worst-case scenario. Fierro calls it “collapse prevention design.”

Enter the Ice Cave

The new addition fills in the middle of the “L,” increasing the floor area from 8,000 square feet at ground level to roughly 11,000 square feet per floor, Chang explains. Consequently, the upper floors cantilever over the plaza below.

Fierro never worked on a nine-story building before, but he was involved in the expansion of the Consortium Library at UAA, where the third floor extends beyond the foundation (and where multi-story windows reveal the structural crossbeams).

The building shape is also a new one for Kirk Malanchuk, the project architect for Perkins&Will. “Structurally, it has garnered its own amount of attention from the engineering community,” he says, “which I think is somewhat representative of the challenge of it.”

One huge challenge is that the foundation was not designed to hold a cantilever, like a diving board nine stories high. Thus, Neeser had to install a new foundation—with the building still on top of the old one.

“The underpinning we did,” Bhargava explains, “by drilling the holes in the concrete to support the existing footings, and then we dug the dirt below the concrete and then put the rebar and poured the concrete. So that was a tricky job.”

The beefed-up foundation takes the load from two angled columns that define the triangular face of the “prow.” But not directly—the design has an additional complication.

For a more inviting entrance from Fifth Avenue, the south leg of the “prow” splits just below the second floor, transferring its load to two smaller columns, both more horizontal than vertical. Indeed, one of them is not designed to hold any weight from above; Fierro says it’s only there for “wind girt” to resist lateral stresses.

The other, shorter angled column does hold weight—up to 1.2 million pounds, Fierro says—but it’s in a more precarious position, parallel to a busy street. “If something happened to that column—if a drunk driver was able to get there and impact it—it could’ve potentially caused some collapse to the addition,” Fierro says, explaining why he calls that crucial piece of steel “The Jenga Column.”

“So I designed the building with the column and without it,” Fierro says. “What I did was, I asked, begged, pleaded with the architects if I could put in something called belt trusses.”

Essentially, additional cross-braces around the second, third, and fourth floors create a box that can do the Jenga Column’s work, in a worst-case scenario. Fierro calls it “collapse prevention design.”

All the Finishes

When the builders achieve a “White Box Finish” this summer, the building will be “T.I. ready,” that is, each rentable floor is a blank slate for tenant improvements. Chang says no new anchor tenant is lined up to replace KeyBank, but he expects multiple law firms to return, as well as federal, state, or municipal agencies.

Hinthorne explains, “You design the lobby, and then you want the rest of the floors to be as flexible as possible to accommodate whoever: multi-tenant, single tenant, big tenant, small tenant. You want to keep the pool of potential tenants as big as you can.”

Whoever occupies the top floor must be a very special tenant. Not only is the floor area the widest (because of the cantilevered prow) but the ceiling is double height. Mechanical systems in the old penthouse have been relocated, allowing the ninth floor to rise to the full 20-foot height of the original roof.

The relocated mechanical systems include three new natural gas-fired boilers, a new air handling unit, and a rooftop exhaust fan. Because of the added interior volume, a larger air duct rises between the core elevators, wide enough for two or three John McClanes to shimmy through. The building also gets updated electrical circuits, switching gear, and LED lighting.

Every detail, from the shape and color of the wooden handrails on the stairs to the texture of the floor in the janitor’s closet, is dictated by the client’s and architect’s vision and executed by the builder. “Whenever we go and we look at the building, we feel proud of it, all the finishes and how our people did,” says Neeser’s Bhargava.

Outside, the grounds are the domain of civil engineers. Chmielowski says DOWL’s landscape architect worked closely with Chang, Perkins&Will, and the Parks & Recreation Department to design replacement plantings that the city can easily maintain. “The final product is a great example of the city and developers working together to have site features that not only enhance the building but also brings a new vision to this area in downtown Anchorage,” she says.

DOWL also was responsible for grading the new plaza and sidewalk, angled just enough to shed stormwater with no more than a 2 percent slope, to meet accessibility requirements. The outdoor surfaces—underneath the looming prow—are also heated by the building’s boiler, to melt snow, and the plaza has inlaid triangular skylights for the enlarged basement.

Future Connections

That’s another thing: the additional square footage includes the basement. The earth under the old plaza was hollowed out, and the lower level now extends all the way to the property line on F Street. What happens to that concrete wall in the future has yet to be decided.
Chang envisions a possible opening to connect to the basement meeting rooms in the Egan Center. Another option is an enclosed bridge over F Street into the neighboring building, right next to the skyway across Fifth Avenue to the Performing Arts Center.

“Most winter cities have skybridges, if not underground connections,” Chang says, “so we have done our share of infrastructure to prepare for future connections.” Sure enough, the new cross-bracing leaves an opening at one corner of the east wall of the mezzanine. “We just want to make sure all that infrastructure is done ahead of time… so when we are ready to jumpstart the huge plan, that can be done without disturbing the tenants in the building,” he adds.

Putting a bridge over a city street is a political matter for another time. What’s certain is that 601 W. Fifth is, all by itself, a new landmark on one of Anchorage’s main avenues.

Anchorage Downtown Partnership (ADP) Executive Director Amanda Moser welcomes the renovation, saying, “The glacier-inspired facade is a delightful that tip to Alaska and our natural beauty while the upgrades and improvements bring the building and the feel of downtown into a more modern space.” Moser says ADP also anticipates further developments for Block 41, the city block that includes 601 W. Fifth at one end and the historic Fourth Avenue Theater at the other.

At one point, Peach Investments proposed a brand-new tower for the block, twenty-five stories high—easily the tallest building in Alaska. Chang says that project has been on the back burner for decades, but master planning continues for Block 41. “601 really jumpstarts this whole development,” he says. “We do see this being a pivot of the core.”

Will that mean more work in Alaska for Perkins&Will? Hinthorne says nothing is imminent, at least not on the scale of 601 W. Fifth. If Chang wants his firm to work on the next phases, though, he says he’s ready and willing.