The first phase of a $1.5-billion development in Westwood, Mass., got under way recently with the fast-paced demolition of about 260,000 square feet of buildings on the site.
Testa Corp. of Lynnfield, Mass., demolished the warehouse and office of the General Motors Parts Distribution Center to clear the way for Westwood Station, a 4.5-million-square-foot development of Cabot, Cabot & Forbes (CC&F). Located next to Route 128/1-95 and the Route 128 passenger station of the Massachusetts Bay Transportation Authority (MBTA), Westwood Station is said to be the largest mixed-use project to get under ay in the Boston area in recent memory. It will include 1.25 million square feet of retail space and 2 million square feet of residential space, restaurants and offices.
Eventually, a dozen buildings will be demolished to make way for the new development. Retail construction will take place first followed by residential units which are to be apartments or condominiums, and offices — the latter to be built based on market needs. According to a spokesman for CC&F, the development will resemble a village, with some residential units over storefronts and an overall pedestrian-friendly design.
He indicated CC&F intends the project to be both innovative and sustainable. In line with this, concrete and masonry debris will be crushed and reused on-site as aggregate fill for roads and walkways. Other materials are also being salvaged by the demolition contractor — a long-standing practice of Testa Corp.
"Anybody can just flatten a building and put all of the debris in a big pile," said Pio Monsini, superintendent for Testa. "But if you do it right and separate the materials, it actually takes less time, gives the project a professional look and saves money," added the 30-year veteran of the demolition industry.
Before Testa set its heavy demolition equipment in motion, the contractor hired an engineering firm to survey the building. Based on their recommendations, Testa worked out a plan to safely and efficiently dismantle the building and facilitate the recycling of almost all of the materials.
Measuring roughly 390 feet by 600 feet by 16 feet tall, the GM distribution warehouse was a steel-framed building with masonry block and brick perimeter walls, steel columns, concrete floor slab, steel beams and bar joists, and metal roofing with asphalt membrane and fiberboard insulation. The lower 4 feet of some of the columns were encased in concrete.
Once all utilities for the building were disconnected, the contractor began stripping away masonry outer walls. Testa's crew employed three CAT excavators with heavy-duty demolition attachments: a 345 with a CAT grapple; a 345 with a LaBounty MSDIOO shear; and a CAT 375 with a LaBounty MSD200 shear. The first two excavators worked as a team to strip the building in sections, while the biggest machine used the huge MSD200 shear to slice large steel columns and other materials to fit into haul trucks. A smaller machine, a CAT 226 skid steer with a CAT grapple, separated debris by type of materials and moved them into separate piles to facilitate recycling efforts.
Testa attacked the structure's fame methodically, working in sections parallel to the long axis of the building, bay by bay, stripping away everything but the columns and the roof they supported. Then the machines peeled away the roof, ripped out the bar joists, knocked down the beams and columns, and moved to the next section.
Materials were separated. Steel columns were placed in one pile, light iron in another, metal roofing, bar joists and iron pipe, miscellaneous non-ferrous metals (copper wire, copper pipe, brass fittings) asphalt membrane, fiberboard, drywall, wood, masonry, and so on. While the machines did the lion's share of the takedown, there was a lot of manual labor involved cutting and separating some of the materials, such as copper and brass and light iron, with workers using power tools to do the cutting.
Most of the demolition debris will be recycled. The brick, block and concrete will be reused on-site as aggregate fill — after being pulverized by Testa's mobile crusher — while the bulk of the remaining materials will go to recycling companies.
Demolition of the office and warehouse got under way in mid-September and was completed in 46 days, about half of the time allowed for the work. Construction of the mixed-use development is expected to begin in spring 2007, once all permits are received from the town.