Developer Hines has broken ground in Minneapolis' North Loop on its all-timber office building, the first commercial property in the U.S. to use an engineered wood material for its interior and structure.

The Houston-based real estate company announced Monday the start of construction on the 220,000-square-foot, seven-story office building (being called T3 for its emphasis on timber, transit and technology) that has garnered national attention.

Hines hired Vancouver-based Michael Green Architecture, in conjunction with DLR Group, to design the building. Michael Green is among the world's foremost experts in heavy timber construction and an advocate for timber as a sustainable building material. While old-growth timber -- the kind needed to support the weight of a tall building -- is unavailable for construction today, an engineering process that presses smaller pieces of wood together can re-create the load capacity of heavy timber.

Following the initial announcement in November, the Wall Street Journal showcased the project, saying it will be the tallest modern all-timber structure in the U.S. once completed. Hines said Monday that it expects the building to open in early fall 2016.

Locally, the building has been the subject of much chatter since Hines is building it without any tenants -- something the industry calls "speculative" development. The T3 site borders two existing Hines properties — the Dock Street Flats and Union Plaza, an office building. To the south is a surface parking lot where Hines, more than two years ago, proposed building a 20-story glass tower.

And while many developers are hesitant to build new office space before signing a tenant, Hines' local leadership said in November they are confident its design will appropriately reflect the historical character of the neighborhood while offering a fresh space for companies looking to attract young talent.

"This office building combines the aesthetic, spatial volumes, and warmth of older brick and timber buildings, with state-of-the-art amenities and systems. This combination of 'old & new' allows for high densification and meaningful recruitment and retention benefits for T3's occupants," said Hines Managing Director Steve Luthman, in a news release.

Jones Lang LaSalle has been hired to lease the space.