Projects

Heartwood is a groundbreaking mass timber residential project in Seattle, designed by atelierjones and developed with Community Roots Housing. It is the first building in the U.S. completed under the new Type IV-C tall wood construction codes, setting a precedent for future developments.

The 67,000 SF, eight-story building provides workforce housing for residents earning 60–100% AMI (Area Medium Income), with 113 studios and 13 one-bedroom units. Shared amenities—including a courtyard, retail space, and bike storage—connect Heartwood with the adjacent Helen V Apartments, creating a unified community.

Built using cross-laminated timber (CLT) and exposed glulam beams, the project reduces its carbon footprint and is targeting 4-Star Built Green certification. The Global Warming Potential (GWP) for Heartwood’s superstructure was 38% lower compared to an equivalent concrete building. When offsetting the CO₂ sequestered in the timber, the net result is a 108% reduction – a carbon negative superstructure.

HV Engineering provided mechanical and plumbing engineering services, supporting efficient, high-performance building systems.