Home AEC 126-Unit Heartwood in Seattle Tops Out as First Type IV-C Tall Mass...

126-Unit Heartwood in Seattle Tops Out as First Type IV-C Tall Mass Timber Building in North America

Seattle, Heartwood, Capitol Hill, DCI Engineers, Puget Sound

SEATTLE, Wash. – Dec. 13, 2022 – On Wednesday, December 14, the structure for Heartwood—the first Type IV-C tall mass timber building in North America—will be completed. Located in Seattle’s Capitol Hill neighborhood, Heartwood is an eight-story, workforce housing building that utilizes cross-laminated timber (CLT)floor panels and a glulam post and beam system.

DCI Engineers, the Engineer of Record and Specialty Engineer on the project, is also providing structural design for 1510 Webster, the first Type IV-A tall mass timber building in North America and first point-supported mass plywood panel (MPP) building in the world. Currently under construction, the 21-story residential building will be the tallest mass timber building in the world in a high seismic zone.

Both structures are the result of a recent code adoption for tall mass timber in the U.S. DCI’s Director of Sustainability & Mass Timber, Ethan Martin, was part of the efforts to introduce tall mass timber to the industry.

“Tall mass timber provides a third data point for building options,” said Martin. “It’s no longer just concrete and steel as your high-rise choices.”

About DCI Engineers
DCI Engineers is a nationally accredited and recognized civil and structural engineering firm. Founded in 1988, DCI Engineers employs more than 350 engineering, technical, and support staff members in Washington, Oregon, Idaho, California, Texas, Alaska, Colorado, Montana, Delaware, and Pennsylvania. Employees of DCI Engineers are respected professionals in their specialties, with grounding in practical design. Many of the firm’s engineers hold advanced degrees and have won numerous design awards.