4 ways prefabrication benefits communities and the environment

Southwest Library
Washington D.C.

The newest library in the D.C. Public Library (DCPL) system has only been open since 2021, but it’s already an icon. Its most striking feature is its “folded plate” roof, which evokes the pages of open books and extends into the neighboring park.

The 17,000-pound mass timber roof panels were constructed offsite and lifted into place via crane in a just-in-time delivery sequence. The resulting building meshes with the neighborhood’s mid-century aesthetic and its natural setting. “When thoughtful design harnesses the power of engineering, it evokes joy,” says Jaspreet Pahwa, DCPL’s director of capital planning and construction. “This building’s placement on the site is like a moment of poetry.”

The library has won numerous design awards, but Pahwa finds even more gratification in the public’s enthusiasm for its distinctive appearance. She recalls visiting a pop-up holiday bazaar where vendors were selling handmade art celebrating DC landmarks and local celebrities, like depictions of the Capitol, Supreme Court Justice Ruth Bader Ginsburg, and the Washington Monument. “It absolutely stopped me in my tracks when I saw an artist selling postcards with a watercolor rendition of the Southwest Library,” she says. “Something becomes iconic when it captures the public imagination, and this library has done that.”

Metro Vancouver SkyTrain
Vancouver, British Columbia

Public transit stations are high-traffic, time-critical environments where safety and convenience are of utmost concern. Maintenance efforts at stations in active operation are complicated by the need to keep passengers safe and trains on schedule.

The Metro Vancouver SkyTrain stations’ prefabricated elements help minimize disruption during upgrades and routine maintenance. “We want to extend the life of these facilities, so ongoing maintenance efficiency is a big consideration for our designs,” says Marco Bonaventura, manager of facility design at TransLink Canada. “We have to consider sustainment beyond opening day. In fact, the bulk of our work involves upgrades or state of good repair.”

For instance, demountable wall panels expedited recent station upgrades, Bonaventura says. “We could augment the existing stations with new interventions quite easily. It minimized the amount of site intervention and potential disruption, particularly to customers but also to operations. It’s one of the leading reasons why we look at prefabricated components.”

Pepper Canyon West Living and Learning Neighborhood
San Diego, California

With two towers and more than 1,300 beds, Pepper Canyon West Living and Learning Neighborhood is a student residential complex that’s intended to help alleviate the student housing shortage at UC San Diego. To ensure high-quality results while meeting a tight construction timeline, the design team specified bathrooms and kitchens that were constructed in a factory and shipped to the site.

It was a smart move, says Dr. Hemlata Jhaveri, senior associate vice chancellor for Residential, Retail and Supply Chain Services at UC San Diego. “The kitchen and bathroom units arrived wrapped and ready to be lifted by the crane, and then they were slotted right in,” she says. Onsite crews could offload approximately four units per hour, or about 24 units on a typical six-hour workday. Later, after the curtainwall was installed, they connected the pre-installed wiring and plumbing to the buildings’ systems, slashing the construction timeline by approximately three weeks.

In all, prefabrication saved approximately $1 million in first costs, or material and labor expenses, and it also generated less construction waste on site, required fewer person-hours, reduced the risk of trade damage, improved the overall project schedule, and elevated quality due to the controlled shop setting. Careful coordination and attention to detail throughout the design and construction process resulted in finished units that are indistinguishable from those crafted by skilled tradespeople on site, Jhaveri says. “They’re beautiful, and quality control is actually better because everything was tested in a factory setting before it arrived.”

Tall Timber Student Housing
Burnaby, British Columbia

Prefabricated elements generate less construction waste and less waste overall because they are manufactured to order, assembled in offsite facilities, and transported efficiently. Mass timber brings even more environmental benefits because trees sequester carbon as they grow and store it when they’re made into buildings. At the British Columbia Institute of Technology (BCIT) in Burnaby, British Columbia, the new Tall Timber Student Housing project provides housing for 469 students, along with common areas and collaboration spaces, via a hybrid structure consisting of steel cores and cross-laminated timber slabs supported by steel columns.

“We’re getting very good at reducing operational carbon, or the amount of energy our buildings consume day-to-day,” says Natalka Lubiw, director of facilities development at BCIT. “Now we’re looking to reduce embodied energy or carbon, and that’s where mass timber can make an order of magnitude difference. Using mass timber reduces embodied carbon by using a renewable resource in place of what would otherwise be a concrete slab.”

Along with prefabrication’s other benefits, the sustainability aspect was particularly important because of BCIT’s educational mission. “The campus itself is a demonstration of leading-edge sustainability practices and integration, and I think this project slots right into that,” Lubiw says. “We train students for construction trades and engineering trades, among others, so this has given them the opportunity to observe and interact with mass timber installers. There’s a lot of opportunity to develop skills and talent.”