New Super-Tall Wood Building Underway in Milwaukee

Ascent Timber Tower from the ground

Currently in contention for the title of “world’s tallest wooden building” is “Ascent,” a 25-story mass timber tower under construction right now in downtown Milwaukee, Wisconsin. Standing 285 feet tall, the residential complex by Korb + Associates Architects benefits from the plans, approvals and fire tests completed for the never-built “Framework” tower previously planned for Portland, Oregon, funded by a $1.5-million U.S. Tall Wood Building Prize.

Ascent, set to open in 2021, will offer 493,000 square feet of mixed-use space, including 258 apartments, a pool on the sixth floor and a top floor amenity level. It will also have a six-story reinforced concrete parking podium with post-tensioned slabs and a full-height reinforced concrete core near the end of each leg.

Ascent TImber Tower

The record-breaking design “exposes the mass timber construction whenever possible to display its natural qualities,” says structural engineering firm Thornton Tomasetti, which worked on the project.

That much is apparent fro the photos. Developer New Land Enterprises wanted the building to have a natural look with a modern edge, and it definitely achieves that, inside and out. The apartments will be made almost entirely from cross laminated timber (CLT), which is made by layering kiln-dried lumber in alternating directions and pressing it together with structural adhesive.

Ascent Timber Tower inside
Ascent timber tower public area

Tall timber buildings always rise concerns about fire. 

“Any building, whether mass timber, concrete or steel, has to meet certain fire codes … that’s in the zoning code,” says Tim Gokhman, managing director of New Land Enterprise, in an interview with OnMilwaukee. “No one in the United States met it yet (with mass timber) because no one’s tried. And so in that sense it hasn’t been done.”

So, in order to get the building approved, the engineers “did the world’s first three-hour fire test,” he explains. The CLT panels were sent to a U.S. Forest Service laboratory on the UW-Madison campus. That’s an hour longer than required to meet the fire codes. “They’re not able to release the official results yet, but the initial feedback is very positive,” says Gokhman.

“Steel will fail at about 1100 degrees, and during our fire test, the temperature exceeded that. They had a rod inside the timber (near) the core of the wood, and it was below 100 degrees. Wood is not a good conductor; as a result it’s a great insulator. If you look at any forest fire and at a cross section of the tree, it right away tells you the same story.”

“The inside of the tree is always intact. It has to do with the density and that outside char layer. But the code already knows this. It’s not like the construction industry doesn’t know this. We can’t have in our building any exposed steel. It has to be protected. So either you spray it or you bury it inside the wood. So the steel is protected by the wood.”

Ascent timber tower water view

When it’s finished, Ascent will beat out the current world’s tallest mass timber building, Mjøstärnet in Norway, by four feet. It’ll also best North America’s tallest timber tower, which is currently Vancouver’s 174-foot Brock Commons Tallwood House. 

Tree Tower: Sustainable Timber High-Rise for Toronto Incorporates Living Plants

timber tower 4

Rising 18 stories from street level in Toronto, with each of its balconies augmented by verdant greenery, this sustainable structure shows off the capabilities of tall timber construction. Penda Architects teamed up with wood consulting firm Tmber to propose a modular high-rise tower built almost entirely from wood. Massive wood panels make up the main structural elements of the building, and the facade is clad in timber panels.

timber tower

Such extensive use of wood in a 200-foot-tall building will be a first for Toronto, and the architects hope it will help jump-start a trend of sustainable wooden architecture throughout the city. They joke that they’re growing the materials for future expansion of the building right on its own balconies in the form of living trees.

timber tower 3

“Our cities are an assembly of steel, concrete and glass,” says Penda. “If you walk through the city and suddenly see a tower made of wood and plants, it will create an interesting contrast. The warm, natural appearance of wood and the plants growing on its facade bring the building to life and could be a model for environmental friendly developments and sustainable extensions of our urban landscape.”

timber tower 2

The connection between the visible wooden construction of the building and the living trees “helps further develop a true ecological high rise, supplies its residents with fresher air and provides a lower carbon footprint,” says Mark Stein, CEO of Tmber. “The extensive use of wood will set ambitious sustainability targets and will be a catalyst for similar developments in Canada.”

The mixed-use building will contain residential units as well as public facilities like a community workshop, cafe and daycare center.

Timber City: A New Trend of Tall Timber Architecture on Display in Washington D.C.

framework building

The National Building Museum in Washington, D.C. doesn’t usually do current events exhibitions, but its curators say that all changed this year with Timber City due to a coming evolution in architecture. Namely: the spread of high-rise wooden structures, which are taking off across the world so fast, we can barely keep track of which one’s currently holding the record as the highest. Timber City examines tall-timber construction as it expands into a contemporary trend, comparing it to growth in the use of reinforced concrete in the early 20th century.

The exhibit shows off a wide variety of new architecture being made with new types of wooden construction techniques, including the use of cross-laminated timber (CLT). While its safety has already been tested and demonstrated convincingly enough to prompt new building codes and the embrace of architects, this type of tall timber architecture won’t be accepted as mainstream until consumers appreciate it for its physical beauty, according to Professor Susan Piedmont-Palladino, one of the project’s curators.

“This fall, the Museum challenges the notion that wood is an antiquated building material when it opens Timber City,” reads the project’s website. “The exhibition demonstrates the many advantages offered by cutting-edge methods of timber construction, including surprising strength, fire resistance, sustainability and beauty. Drawing attention to the recent boom in timber construction worldwide, Timber City further highlights several U.S. based projects, including two winners of the U.S. Tall Wood Building Prize, sponsored by the U.S. Department of Agriculture, in partnership with the Softwood Lumber Board and the Binational Softwood Lumber Council.”

The exhibit went up on September 17th and will remain in place through May 21st, 2017, so if you get a chance to visit Washington D.C., pop into the National Building Museum and check it out.

Pictured: The 130-foot-tall Framework Building in Portland, Oregon