(The following article by Michael Luo was posted on the New York Times website on July 26.)
NEW YORK — The outsize proportions of Grand Central Terminal are what capture attention, not its color. So it is hard to say how many tourists who snap pictures of the Beaux-Arts landmark, or passers-by who glance up at the imposing columns that front the station’s southern facade, have noticed that the building is filthy.
But look at any color postcard or photograph closely, allowing your gaze to drift downward from Jules Coutan’s famous statue of Mercury, flanked by Minerva and Hercules, atop the terminal, to the granite base at street level, and it is obvious: after 91 years, the building’s limestone exterior is mossy brown.
Since October, scaffolding and dark netting have shrouded the terminal’s western side, over the Vanderbilt Avenue viaduct.
Workers had been giving the building a long-overdue shower, setting up a long pipe with multiple heads that spray a steady mist onto the facade. Water was applied to a section six hours a day for two weeks before workers moved the assembly to a new spot.
Then, they went over the area with a power washer, turned to its lowest setting, gently ridding the wall of decades of accumulated New York City grime.
A peek under the netting the other day with Wayne Ehmann, chief architect for the Metro-North Railroad, revealed the stark difference: a gleaming white-gray wall of unblemished Indiana limestone.
In a month or two, the same shrouding will go up on the more visible southern face so it can undergo similar treatment.
The eastern side will follow soon after, assuming financing can be arranged in the Metropolitan Transportation Authority’s next five-year capital plan.
Only the northern side, which abuts the Met-Life building, will not be washed.
The results, say those who have worked on the restoration, will be dramatic.
“When the netting finally comes down, it’s going to really be a shock,” said Steve Triano, the construction manager for Metro-North.
Said Mr. Ehmann: “You’ll be looking at what looks like a brand-new building.”
Besides giving the building a scrubbing, workers are repairing cracks, repointing all 23,457 stones on the facade and replacing missing pieces, all part of more than $21 million in final touches to a restoration of the historic terminal that began more than a decade ago.
The landmark building, designed by Whitney Warren, has come a long way since its heyday during World War II, when rail travel in the United States was at its peak. Gradually, the terminal fell into a state of disrepair. It was almost gutted and turned into an office building during the 1960’s, but a group of preservationists, including Jacqueline Kennedy Onassis, intervened and got the building designated a historic landmark.
A string of railroads owned the building afterward, only to go bankrupt. When Metro-North took over Grand Central in 1983, almost nothing had been spent on maintenance in years.
“Metro-North inherited original utilities, boilers, plumbing, wiring, everything,” said Marjorie Anders, a spokeswoman for the railroad.
At the time, the copper roof was the most obvious need because it was leaking, leaving streaks on the vaulted ceiling over the main concourse. After it was repaired, work began on the statuary atop the terminal. Then, in 1987, the railroad hired a firm to perform a complete assessment of the building and set out a repair plan.
Work finally wrapped up on the terminal’s interior in 1998. It included a painstaking restoration of the fabled sky ceiling that serves as the backdrop for 2,500 gold-painted stars and had gone from deep blue to algae green.
The exterior was in relatively good shape when the assessment was made more than a decade ago, but by the time officials got around to inspecting the exterior again last year, serious problems had begun to emerge.
The most pressing concerns were problems in the building’s skin that might lead to more water leakage and structural damage. Consultants from Building Conservation Associates, a firm specializing in restoration, and others from Metro-North went up in bucket trucks to inspect each stone on the building’s facade, mapping it and identifying which needed to be replaced.
In certain spots, entire blocks were removed so workers could peer inside. They discovered that water had infiltrated through cracks in the brick, corroding sections of the building’s steel frame.
While examining each stone, banging each with a mallet to test its soundness, they discovered cracks in the intricate molding below the building’s cornice, the stone lip that encircles the top of the building 80 feet above the viaduct. Pieces were loose, and some could even be pulled out by hand, so workers quickly set up a protective netting around the entire cornice in case a piece broke away.
Engineers also studied various techniques for cleaning the facade. The soot that mars the buildings actually comes from pollutants in the air that react with the limestone to form a thin black crust, said Raymond Pepi, president of the consulting firm that helped in the restoration. They tried out various chemicals but elected in the end to use water, he said. The strategy was to loosen the grime with a fine, continuous mist, so it can then be washed away.
“The theory behind this is it’s not so much the quantity of water you put on the building as it’s just important to have a very fine mist, this nebulized mist, hitting the wall over a period of time,” Mr. Pepi said.
Besides the more visible work on the facade, some of the most important restoration is taking place out of public view. A portion of the roof over the vaulted ceiling is being replaced with a new high-tech epoxy membrane that should last 30 years. The flat roof in two northern and southern roof courtyards that provide light and air to the terminal will be redone as well. Cracked brick in the courtyard walls, which has led to water damage, will also be replaced.
These courtyards are what sit behind the series of large, half-moon shaped windows that tower above the main concourse. It is through these windows that light streams through in diagonal rays in the iconic black and white photographs of the terminal’s interior.
Those windows are now boarded up as workers fix the glass panes that covered them, because some had cracked over the years or were missing. The glass, with hexagonal wire inside for fireproofing, is no longer being made, but Metro-North officials stumbled upon some old stock in the Queens warehouse of a supplier.
The light that usually pours through the windows reflects off the walls of the roof courtyards into the concourse. Initially, Mr. Ehmann said he thought the brick was naturally dark-colored, until workers conducted some tests. It turned out they were supposed to be cream.
The difference was obvious the other day in the southern courtyard, where one side’s walls had been cleaned, while a lone worker scrubbed away, inch by inch, the ashy blackness remaining on the other.
In this case, a mild solvent was applied to the brick, then a worker came through with a heavy-bristled brush, wielded like a giant toothbrush. It takes six workers a month to clean an entire courtyard. Afterward, people in the concourse should be bathed in substantially more light, Mr. Ehmann said.
On the facade, the most laborious task is the repointing of each piece of limestone. Over time, the mortar between the stones deteriorates and has to be scraped out and replaced. Consultants devoted much time to testing the old mortar and coming up with a recipe that matched it.
During a visit the other day, seven stories above the viaduct, a worker was applying new mortar to the joints above one of the three monumental windows on the western facade. The window frames are also being repainted the traditional light green hue that workers call Grand Central green, because of its ubiquity throughout the station, and the windows themselves cleaned. Meanwhile, down below, another worker used a power saw to cut a foot-long section of limestone to replace a missing piece up above.
Most of the western facade has been washed by now, but a band near the roof has not yet been cleaned, appearing almost black up close.
The section should be taken care of soon, however, after workers repair the cornice. Only then will the western side be ready for its unveiling, which should take place in the next few months. Mr. Ehmann believes all the work should be done by 2007.
At that point, he said, it should be just about time to start all over again on the inside.