Hitting the bricks — gently
|By Lawrence Cosentino|
Masons restore a colossal flame to its original gloryThe most compelling reason to spend millions of dollars to gut, refit and save the Ottawa Power Station is its unique shell, tapered and colored like a giant flame burning from black at the bottom to red to orange to yellow on top.
But Douglas Armstrong, masonry point man for the Ottawa project, saw trouble as soon as he climbed up to the top of the fifth floor to hang the banner announcing the redevelopment in October 2007.
On a diagnostic tour, Armstrong picked his way across the top of the building with his boss, Mike Maher, interim president of Schiffer Masonry of Holt.
As they walked the parapet 172 feet up, they found the top nine feet of the building ravaged by water and corrosion. All four corners of the roof were crumbling and had to be rebuilt.
Where the elements were harshest, a dreaded process called “rust-jacking” had run amok. Structural steel that was close to the walls had expanded over the years, rusting as it thickened. The original builders didn’t use expansion joints, standard in today’s work. The steel broke the brick loose, letting in more water and accelerating the rust and decay.
Some beams expanded to nine times their original thickness, lifting and cracking the masonry.
As snowflakes flew in early 2008, a crane painstakingly lifted the cream-colored limestone slabs that frost the top of the plant. Workers reinforced the roof with concrete and the slabs were laid back on, this time with modern flashing and other barriers against the elements.
Then the real work began. Bringing the plant’s masonry back to life was like painstakingly restoring Da Vinci’s “Last Supper,” with restorers the size of ants. The job would drag on for two and a half years.
Working down from the top, masons cleaned or replaced every single brick in the plant’s enormous brick envelope, making hundreds of patches along the way. Each window or projection — and there were a lot of them — offered a path for water and a different pattern of corrosion.
The scaffolding and swing stages alone were a temporary work of art, a web of steel beams cantilevered out of windows and over the plant’s telescoping floors, tested and re-tested for stability.
“The team didn’t know what loads the building could take,” Maher said. “Everything we did presented a challenge up there.” Maher, Armstrong and his team worked closely with the general contractor, the Christman Co., and historic preservation architects from Ann Arbor’s Quinn Evans, emailing photos of trouble spots back and forth.
“Every window head and pilaster [vertical column] had a different issue that needed quick action,” Maher said. “You can’t have guys waiting around for an answer.”
About 95 percent of the bricks were salvaged, but that still left a lot of holes to fill.
The masonry team found a perfect match for the yellow bricks at the top. The darker bricks at the bottom were easier to scrounge from infill or unseen parts of the building. But the orange bricks in the middle of the building were almost impossible to match, because they are tinted by embedded flecks of iron. Edison Coatings, a Connecticut company specializing in custom stains, brewed up a four-coat stain that matched the original color. The masonry team tested the coating with ultraviolet rays and simulated snow and rain to make sure the color wouldn’t fade.
Every new brick had to match the original design. The U.S. Department of the Interior, guardians of the plant’s historic status, visited the site every month to check on the job.
Frustratingly, the masons on their scaffolds were too close to see their own work.
The plant’s original builders daubed the multi-colored bricks on the shell like Impressionist painters, diffusing colors to mimic the fluidity of flame. The effect was spectacular, but could only be seen properly from the ground.
So passersby often saw Armstrong standing across the Grand River or on Grand Avenue, peering through binoculars, telling a mason via cell phone to move three orange bricks to the right.
To complicate matters, masonry takes 28 days to cure and changes color as it cures.
For a long time, the ghost words “Board of Water and Light” refused to go away, owing to a difference in weathering under the letters. (The letters, put up after 1965, weren’t part of the plant’s original design. The Lansing Board of Water & Light took them down and disposed of them in late 2007.)
The building seemed haunted by its first life. More than once, Maher went across the river to the City Market, looked back at the plant and saw stubborn ghost letters re-appear as much as a month after a cleaning.
Sandblasting was too abrasive, but a combination of gritty cleaning agents, including walnut shells and corncobs, finally exorcised the ghosts.
By summer 2009, work settled into a routine. Armstrong would approve of a segment and show it to Christman for the go-ahead to move the scaffold to the next section.
Armstrong took special pride in brewing up a latte-colored custom mortar blend that exactly matched the original.
“We matched the mortar without creating a patchwork on the building,” he said. “You can hardly see where we applied the new mortar.”
The masonry work alone required 30 men on site in summer, with an average of six to eight workers over the whole job.
Schiffer Masonry has a lot of experience with new buildings like the state Hall of Justice, MSU’s Breslin Center and several state prisons, but Maher said the Ottawa Station is the biggest historic preservation project it has undertaken by any measure.
It was also the most unusual. As the masons worked, they did the dance of two swinging cranes with another contractor, Douglas Steel Fabircating Corp., of Lansing.
While the steelmen ripped out the building’s skeleton and rebuilt it from the inside, masons repaired and rebuilt the shell. The cranes had the same radius, so there wasn’t room for error.
The work even went through an aquatic phase.
“We had swing stages over the river, with boats and a life raft,” Maher said. “Guys working over the river had to wear not only a safety harness, but also a floatation device! That’s pretty unique.”
Now Maher and Douglas like to stop by and watch the sun hit the west face in the morning.
“It’s nice to see they saved a piece of history instead of tearing it down,” Douglas said.
To ensure that the shell doesn’t go to seed again, the masons worked out a maintenance program with Christman Co., the building’s owner and project contractor, with one- and five-year inspections of potential problem areas.
Maher said that if moisture is managed properly, the giant flame will warm downtown Lansing for decades to come.
“Masonry has been around for thousands of years, since the pyramids, and it’s the same old stuff,” he said. “They did it in 1939, so I don’t see any reason why we can’t do it now.”