Over the past ten years, Boston-based firm Leers Weinzapfel Associates has emerged as a leader in the United States’s burgeoning mass timber design industry. The studio first worked with cross-laminated timber (CLT) in 2013 when it began work on the John W. Olver Design Building at the University of Massachusetts, Amherst. More recently, in 2019 Leers Weinzapfel completed the University of Arkansas’s Adohi Hall, the largest CLT building in the U.S. and winner of many accolades, including a WoodWorks Design Award announced in AN’s 2020 timber issue.
Tom Chung, one of Leers Weinzapfel’s principals, said that the firm is bullish on mass timber for its many obvious, pragmatic advantages: it’s a renewable resource, has a less carbon-intensive manufacturing process than concrete or steel, and can be locally sourced across much of the country. But for Andrea Leers, cofounding principal, the material’s advantages go beyond economic or even ecological considerations. “The contentment that comes from being in a wood environment is a huge incentive,” she said. “The smell of the wood, the feel of it, the appreciation of it is something rooted in human experience. Everybody knows wood. Everybody’s touched trees. It’s very immediate.”
Chung agreed. “Andrea and I, as we’ve practiced, we’ve heard people say, ‘Oh, I don’t like this building because there’s too much concrete or too much steel. It feels cold.’ I’ve never heard anybody complain [about a building] that there’s too much wood.”
The John W. Olver Design Building at the University of Massachusetts, Amherst, 2017
Leers Weinzapfel’s first mass timber project, a new home for the University of Massachusetts, Amherst’s design programs, was originally supposed to use a steel structural system, but representatives from the school’s building construction and technology program suggested that the firm consider engineered wood. “We have always been a firm interested in material research and development,” Leers said, “so we saw this as a great opportunity to learn a new building system.” Translating elements like 60-foot-spanning steel members into timber presented many challenges, and solutions like the massive zipper trusses in the main hall combine to create the firm’s most complex timber structure.
Adohi Hall, 2019
Administrators at the University of Arkansas wanted Adohi Hall, a 708-bed dorm Leers Weinzapfel designed with modus studio, Mackey Mitchell Architects, and OLIN, to be a mass timber building from the project’s start. (With help from Walmart and Ozarks woodlands, Arkansas is becoming a center for mass timber construction.) So the architects closely adhered to local timber code restrictions, which limited the building’s height, and the dimensions of available CLT systems, which helped determine the dimensions of the living units. Because timber cladding can be difficult to maintain at this scale on a relatively tight budget, the architects opted for a “light metal jacket,” Leers said, but left wooden ceilings exposed in student bedrooms so the material would be felt throughout the building.
Kreher Preserve & Nature, Center Preschool, 2022, anticipated
Auburn University’s School of Forestry and Wildlife Sciences runs a small, nature-focused preschool that immerses children in the great outdoors. “For the students’ typical class day they’re running around in the forest observing nature, looking at the ecology, playing with animals and insects,” Chung said. “All the fun things that we all wanted to do at camps growing up.” The Alabama school tapped Leers Weinzapfel to design a hub for the preschool’s trail-based learning in the 120-acre Kreher Preserve in the city of Auburn. The site is less than 200 miles from a CLT plant in Dothan, which will turn trees cleared for the project into wood products and supply materials used in the building. Given the project’s forested site, the architects wanted to make as much of the building as possible out of wood. When finished next year, it will have wooden ceilings, walls, and floors; a CLT structure made of local loblolly pine; and wooden piles instead of a concrete foundation.
Innovation Center, 2022, anticipated
On the site of Suffolk Downs racetrack in Revere, Massachusetts, north of Boston, HYM Investment Group is building a multiacre, mixed-use complex, and the developers asked Leers Weinzapfel to design a small gateway building for the project. When it opens in 2022, the Innovation Center, as the building will be known, will have coworking spaces on its upper floors laid out in a 20-by-25-foot grid determined by the mass timber structure. “The signature piece is the roof canopy, a gently curving, sail-like, wave-cresting form that recalls the nearby Revere Beach,” Chung said. The roof will cantilever over a terrace that is part of the central public space for the development.