CTBUH certifies Ascent as World’s Tallest Mass Timber Building
The Council on Tall Buildings and Urban Habitat (CTBUH) has officially declared the recently-opened Ascent tower by Korb + Associates Architects the world’s tallest timber-concrete hybrid building. The 25-story, 86.6-meter (284-foot) structure in Milwaukee takes the distinguished title in two of the mass timber categories: It is both the tallest timber building overall and the tallest concrete-timber hybrid building.
The previous world’s tallest timber building was Mjøstårnet in Brumunddal, Norway, certified by CTBUH in 2019, which stands at roughly 280 feet. Previously holding the record of tallest concrete-timber hybrid building was the approximately 276-foot HoHo building in Vienna, Austria.
The building features 259 luxury apartments, retail space, an elevated pool with operable window walls, and a sky-deck.
In May of 2019, Ascent was named a recipient of a U.S. Department of Agriculture grant awarded through the Forest Service’s Wood Innovations Grant program. The federal grant assisted with the testing needed to prove mass timber’s ability to perform as well as traditional building materials like concrete and steel to meet U.S. building codes.
Plans for the project were unveiled in 2018.While the initial design included 21 floors,updates and subsequent approvals brought the total to 25 floors in March of 2020.
The project had been presented at the 2018 international CTBUH conference in Dubai, the 2019 international CTBUH conference in Chicago, and the 2019 International Mass Timber conference in Portland.
The Ascent development was constructed using a digital twin model, allowing for materials, such as beams, columns, and panels, to arrive on site ready to use with holes pre-drilled to within 1/16-inch accuracy. According to CTBUH, it is estimated that using mass timber for the project decreased construction time by approximately 25 percent compared to a conventional, similarly-sized concrete building.