Minneapolis’ Warehouse District may soon be home to a milestone in wood construction. Designed by Michael Green Architecture, real estate firm Hines Interests’ proposed T3 office tower (T3 stands for timber, technology, and transit) would be the tallest mass timber building in the United States.
The seven-story, 263,000-square-foot office block includes a concrete and steel foundation and first floor, plus an additional six floors constructed from engineered wood—primarily glulam and cross-laminated timber. The exterior is clad in corrugated weathering steel punctuated by large windows. On the interior, exposed mass timber beams recall heavy timber construction.
“This will have the ambience of the old warehouses with timber beams that everyone wants, but solves all the problems of energy efficiency and light,” Hines director Bob Pfefferle told the Minneapolis Star Tribune.
Engineered wood is an appropriate structural choice for tall buildings for several reasons, said Perkins+Will’s Rebecca Holt, primary author of the Survey of International Tall Wood Buildings. First, she said, it delivers double benefits in terms of carbon emissions. “Not only does it have a lighter carbon footprint, but it also sequesters carbon,” explained Holt. “It is a very environmentally responsible material.” Mass timber supports an efficient building envelope, and lends itself to prefabrication. Engineered wood is also lightweight. Finally, said Holt, “the quality of space cannot be ignored. For a lot of survey participants, that was one of the main reasons for choosing it.”
Despite the advantages associated with mass timber, T3 is moving ahead at a glacial pace. Hines initially anticipated breaking ground in June 2015, but pulled back marketing for the project shortly after unveiling it in November. (The developer declined to provide an interview for this article.)
The issue may be one of perception. “An obvious hurdle for timber construction is how people perceive it—from users to code officials, potential buyers, and the construction industry,” said Holt. “We know how to do what we know how to do well. Changing is a little scary.”
In February, at a meeting before the local heritage board, Hines’ Pfefferle indicated that the developer was still in talks with prospective occupants.
Whatever the holdup, Minneapolis—and the American AEC industry in general—has a lot to gain if T3 gets built. “It looks like it’s going to be a beautiful project,” said Holt. “Of course, any great example that’s solid, that performs well—we need that. People need to touch and feel it in order to see its potential.”