Seattle, Washington

Building Type


Square Footage


Located in Seattle’s vibrant Capitol Hill district, Heartwood is an eight-story apartment building focused on sustainability, affordability, and community. As the first Type IV-C building being constructed in the US under the updated 2021 International Building Code (IBC), it is expected to be one of Seattle’s largest mass timber structures. The beautiful exposed CLT ceilings and Glulam columns within the apartments offer a unique cabin-in-the-woods feel, but with all the comfort and convenience of high-rise city living. The densely populated neighbourhood boasts plenty of amenities and local businesses within walking distance, along with public transit access to farther locations such as the neighbouring central business district. Despite this prime location, Community Roots Housing made sure the 126 units were accessible with affordable rent for middle-income residents.

It is not hard to see that sustainability is at the core of Heartwood’s design. Mass timber was chosen for its reduced construction schedule and energy usage compared to steel and concrete. What’s more, the timber was sourced from within 400 miles of Seattle from sustainably managed forests, further displaying the commitment to environmentally conscious building practices and supporting local industries. The Glulam post-and-beam frame and CLT floors together store 1,050 metric tons of CO2 while being as efficient as possible with the connection hardware used. This, along with the walkability of its location and building amenities such as bike storage and outdoor community spaces, establishes Heartwood as a model for sustainable development and mass timber construction in Seattle.

Sign Up

Register for a Technical Learning Session


Sign up for MTC Newsletter and keep up to date with all our progress.