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Heavy coordination work and use of prefabricated materials are saving Andersen Construction time and money as it builds the Cosmopolitan – a 28-story, 150-unit condominium tower – at Block 15 in the Pearl District.

Roughly 95 percent of the coordination work occurred before foundation work started last week, said Brad Nile, Andersen’s project executive. The contractor and design-build team members Boora Architects and KPFF Consulting Engineers relied heavily on Building Information Modeling software to align all pipes, ductwork and vertical columns, he said.

“In the old school, everybody’s digging out there fighting for position to see who is going to be first to get stuff in the ground,” he said. “Here, we’ve got a logical path. The field crew (members), if there is doubt, come in here and look at the model to see where they’re going.”

The use of BIM helped overcome the biggest challenge – how to maximize the 8,500-square-foot footprint, said Doug Shapiro, director of construction for Hoyt Street Properties, which is developing the project.

“Coordination is probably the biggest savings,” he said. “With the model, we were able to sit with the preconstruction team and resolve conflicts. That helps the construction process, which saves time, which is cost.”

BIM paved the way for substantial use of prefabricated materials, which will cut down on labor and time needed to install items on site. Most trades working on the site will prefabricate their materials, Shapiro said.

Electrical panels will be prewired off site, requiring limited cutting when they are installed. Plumbing and sprinkler lines also will be prefabricated and assembled on site. Other prefabricated parts include cabinets shipped from Italy and a German-made high-density foam showering system. Both will be ready to install.

Another prefabricated element, a curtain wall window system supplied by Portland-based Benson Industries, will essentially be snapped into place, Shapiro said. Unlike a window wall system, fixed between the ceiling above and floor below, the curtain wall system will hook onto the building’s exterior face. The system has been used on other large projects, including the Edith Green-Wendell Wyatt Federal Building in Portland and the Freedom Tower in New York City, said Garry Peters, project manager for Benson Industries.

“What’s nice about the system is that we can control seals and assembly in factory conditions so we know it’s all airtight and goes in as it should be,” he said.

The glass will contribute to the tower’s sleek and slender look upon completion in spring 2016, said Brad Demby, project designer for Boora Architects. The tower will be the tallest in the Pearl District, he added.

“The goal was to have a glassy building that reflected the sky around it,” he said. “That part of the Pearl – the North Pearl District – is trying to be brighter and lighter than the Brewery Blocks. We think this tower will epitomize this new vision.”

The Cosmopolitan

Location: Pearl District

Cost: $115 million

Construction start date: July 2014

Anticipated completion date: April 2016

Owner: Block 15 LLC

Architect: Boora Architects

Landscape architect: 2.ink Studio

Engineer: KPFF Consulting Engineers

General contractor: Andersen Construction