First Type IV-C Tall Wood Building in the U.S.
Heartwood | Seattle, WA
Overview
Heartwood is at the heart of Seattleās affordable housing initiatives. At eight stories and 70,000 gross square feet in the Capitol Hill Neighborhood, the Community Roots Housing project is the first tall wood building permitted by Seattle and received a $250,000 Wood Innovation grant from the U.S. Forest Service to validate the feasibility of Type IV-C multifamily housing. Mass timber was selected for the opportunity it afforded for an additional floor of units (compared to the more conventional 5-over-2 approach) and for its reduced construction schedule. When completed, Heartwood will provide 126 affordable units to a neighborhood experiencing the pain of the high cost of living.
The glulam post-and-beam frame is laid out perpendicular to the corridor, aligning with demising walls between units. This layout facilitates the horizontal distribution of services throughout the building and allows for strategic encapsulation of some timber elements as a cost-saving strategy. To deliver this fully exposed timber structure, Timberlab worked with the design team to develop a wood-to-wood bearing connection that eliminates steel hardware, saving both time and money.
Awards
WoodWorks 2022 Design Award
Team
Owner | Community Roots Housing
Developer | Skipstone
Architect | atelierjones
Structural Engineer | DCI Engineers
General Contractor | Swinerton