Milwaukee is home to the world’s tallest mass-timber building

Work is complete on the mass timber Ascent apartment tower construction site in downtown Milwaukee (Photo: Reuters)

It’s official: The world’s tallest mass-timber structure is located in none other than Milwaukee, Wisconsin.

The 284-foot tall high-rise apartment complex - known as Ascent - has been recognized by the Council on Tall Buildings and Urban Habitat (CTBUH) as the World’s Tallest Timber-Concrete Hybrid Building.

The 25-story building contains 259 apartments and its mass-timber residential floors are constructed above a five-story concrete parking garage using a system of glued-laminated timber, or glulam, beams.

Columns support cross-laminated timber floors, with two concrete cores providing lateral stability. Post-tensioned concrete beams transfer loads from the residential floors to the concrete garage structure below.

Around 50% of Ascent’s mass timber structure remains visible inside the building, so residents can see and touch it.

Mass timber construction, in contrast to light-frame wood construction, is built using a category of engineered wood products typically made of large, solid wood panels, columns or beams often manufactured off-site for load-bearing wall, floor and roof construction.

Engineered for high strength ratings like concrete and steel, mass timber is significantly lighter in weight. It’s considered an environmentally friendly substitute for carbon-intensive materials and building systems.

In the case of Ascent, it’s estimated that using mass timber for the structural system decreased construction time by approximately 25%, compared to a conventionally constructed concrete building of the same scale. Ascent was built using a digital twin model, so every beam, column and panel could arrive on site ready to assemble, with holes predrilled.

The process of constructing Ascent brought together experts from around the world and it is hoped that it has established a model for future tall timber projects.