Created on Thursday, 06 March 2014 11:51 Published Date Hits: 2984
Don’t look for any fireworks — or a big implosion — during the demolition of the old Parmly Billings Library.
The three-story building, constructed as a heavy-duty warehouse, will come down in stages, chipped away at by a crew of four people. If all goes well, they will be done by mid-May and a 102-space parking lot will be open by mid-June.
That will be welcome news for the large crowds that have been frequenting the new Billings Public Library since it opened Jan. 6 just north of the old library.
That proximity of the old and new means the demolition will be a delicate business. Larry Matson, the owner of L.M. Excavating of Columbia Falls, the demolition company bringing the old library down, said he and his three workers will start on the northwest corner of the old building, nearest the new library.
“So we get rid of imminent danger to the new library right off the bat,” he said.
L.M. Excavating is working as a subcontractor for Jackson Contractor Group of Missoula, which submitted the low bid to build the new library.
Mike Chase, Jackson’s project manager, said Matson and his crew are in the “soft demo stage” right now. That means they will be removing everything recyclable from the library’s basement and three floors. That includes ceiling tiles, interior partitions, glass, wooden casework, wiring, toilet fixtures and light fixtures.
That stage will also involve hand-demolishing the rooftop penthouse that used to serve as an employee break room and conference room.
L.M. Excavating started two weeks and will be doing the soft demolition for about a month before it starts taking the old library down, Chase said. The initial work on the northwest corner will be done “in a much more slow-paced, controlled fashion” to prevent any damage to the new building, he said.
The workers will sometimes be using hand tools, and a safety barrier will be erected between the old and new buildings in case any debris goes flying. At the start, they will be using a man lift with a 65-foot reach to knock the exterior walls toward the inside of the old building, but most of the demolition will be done with a Komatsu PC308 excavator.
Matson said the library is basically a series of square boxes supported by concrete columns, with brick walls and concrete floors and ceilings. Starting on the ground floor, he said, “What we’ll do is chew away one column line at a time.”
Rubble and soil will be pushed into a mound 15 feet high and the excavator will sit atop the mound to reach the higher parts of the building.
As each square or bay is demolished, holes will be punched in the floor, allowing the debris to fall into the basement. As part of pre-construction work on the new library and the demolition, Chase said, the weight of just the brick and concrete in the old building was estimated at 12.3 million pounds.
Using a concrete pulverizer attached to the excavator, Matson’s crew will grind the brick and concrete into relatively fine material that will be compacted in layers as it fills up the basement.
Pulverizing the concrete will also enable the crew to remove the steel reinforcement bar. Matson said they expect to remove hundreds of thousands of pounds of steel. The recycling is not only being done to make money; it is also part of the project’s LEED requirements, used to measure energy efficiency and sustainability.
As part of the LEED process, Matson will also be punching holes in the floor of the basement so the site of the old library acts like an enormous French drain, allowing water to percolate into the ground without entering into storm water drains and discharging into the Yellowstone River.
Matson, who has been in the excavating business for 20 years, said he’s worked on buildings like the old library before, including a four-story brick-and-concrete school in Whitefish.
After the building is down, the rubble will be compacted and the site of the old library will be paved over to create the 102-space parking lot. There will also be a walled-in courtyard outside the new library’s community room.
The contract calls for completion of demolition by no later than June 30, but Matson is confident they can be done by mid-May.
“And that’s being realistic,” he said. “If we can get done before that, that’s great.”