First Modern Tall Wood Building in the U.S.

The T3 office building in Minneapolis Designed by Michael Green Architecture (MGA) and architect-of-record DLR Group for real estate firm Hines, T3—short for “Timber, Technology, Transit”—is a seven-story, 220,000-square-foot structure scheduled to open later this month. It will be the largest mass timber building in the United States. MGA associate Candice Nichol says Hines wanted to use mass timber as a differentiator: “Hines understood that the market is looking for office spaces that people actually enjoy working in.” The simple, boxy design picks up visual cues from neighboring historic structures in Minneapolis’ North Loop district. From a distance, the structure looks like another speculative commercial building with a conventional column grid and repetitive floor plates. Yet how it performs both structurally and aesthetically reveals another story. T3 uses spruce-pine-fir NLT panels combined with a spruce glulam post-and-beam frame, and a concrete topping slab. NLT was chosen because it was slightly more economical than other mass timber systems, at least for now. “The T3 structural framing system—columns on a 20- to 30-foot-grid, beams running one direction between columns, and panels spanning across the beams—is an efficient one,” says Lucas Epp, a structural engineer and 3D manager at Delta, British Columbia–based fabricator StructureCraft. The system’s efficiency extends to the material sourcing and construction processes. Most of the project’s lumber came from trees in the Pacific Northwest region killed by the mountain pine beetle. Classified as a “Type IV–Heavy Timber” system by the Minnesota State Building Code, the sprinklered building is not required to have a specific fire rating. However, Epp anticipates the structure to achieve an equivalent rating of more than three hours based in part on the protective charring phenomenon of wood. The timber structure also lends itself to material and cost savings in interior finishes. Commercial buildings typically obscure their structure behind gypsum wallboard and acoustic ceiling tiles because not all occupants appreciate the look of exposed concrete or steel and its requisite fireproofing. Though its exterior is clad in weathering steel, its interior is simply the timber framework. The T3 office building in Minneapolis Designed by Michael Green Architecture (MGA) and architect-of-record DLR Group for real estate firm Hines, T3—short for “Timber, Technology, Transit”—is a seven-story, 220,000-square-foot structure scheduled to open later this month. It will be the largest mass timber building in the United States. MGA associate Candice Nichol says Hines wanted to use mass timber as a differentiator: “Hines understood that the market is looking for office spaces that people actually enjoy working in.” The simple, boxy design picks up visual cues from neighboring historic structures in Minneapolis’ North Loop district. From a distance, the structure looks like another speculative commercial building with a conventional column grid and repetitive floor plates. Yet how it performs both structurally and aesthetically reveals another story. T3 uses spruce-pine-fir NLT panels combined with a spruce glulam post-and-beam frame, and a concrete topping slab. NLT was chosen because it was slightly more economical than other mass timber systems, at least for now. “The T3 structural framing system—columns on a 20- to 30-foot-grid, beams running one direction between columns, and panels spanning across the beams—is an efficient one,” says Lucas Epp, a structural engineer and 3D manager at Delta, British Columbia–based fabricator StructureCraft. The system’s efficiency extends to the material sourcing and construction processes. Most of the project’s lumber came from trees in the Pacific Northwest region killed by the mountain pine beetle. Classified as a “Type IV–Heavy Timber” system by the Minnesota State Building Code, the sprinklered building is not required to have a specific fire rating. However, Epp anticipates the structure to achieve an equivalent rating of more than three hours based in part on the protective charring phenomenon of wood. The timber structure also lends itself to material and cost savings in interior finishes. Commercial buildings typically obscure their structure behind gypsum wallboard and acoustic ceiling tiles because not all occupants appreciate the look of exposed concrete or steel and its requisite fireproofing. Though its exterior is clad in weathering steel, its interior is simply the timber framework.