The state’s tallest mass timber project is opening soon in Seattle

Heartwood is an affordable housing project in Capitol Hill.

A rendering of the outside of Heartwood, an affordable mass-timber apartment building in Capitol Hill, Seattle.

Heartwood offers studios and one-bedrooms at below market prices.

Photo via Heartwood

Heads up, architecture nerds. We’re lumbering up to Capitol Hill to gaze at an intriguing new apartment building made nearly entirely of wood.

With a planned mid-December debut, the eight-story Heartwood (ah, clever) is the tallest construction of its kind in Washington. It’s also part of an affordable housing initiative from local nonprofit Community Roots Housing with units part of rent restriction programs.

So, put on your hard hats as we take a quick tour of the woodsy complex at 1323 E. Union St.

Mass appeal

Heartwood is a mass-timber project, meaning that its core materials were built primarily with either solid or engineered wood rather than steel + concrete (though some steel is used). Why is that a big deal?

  • Materials are locally sourced — all of Heartwood’s components came within 400 miles of the job site.
  • Workers can build it quicker (the building’s materials took only two hours to unload).
  • Construction promises to be cheaper in the long run.
  • It may be friendlier to the environment since wood stores carbon.

According to independent researchers, Heartwood’s carbon footprint was 40% less than comparable construction and the materials are likely to have a lower impact on the environment over the building’s lifespan.

Standing tall

You may be wondering if such a building is susceptible to disasters. But mass timber constructions are designed to be fire resistant. And this summer, researchers conducted an earthquake test of a 10-story mass timber building simulating conditions in Capitol Hill — it passed with flying colors.

Meeting high expectations, Heartwood’s architect hopes to replicate the building’s design for even taller projects, aiming to cut down construction time and emissions in the process.

With all that build up, Heartwood is currently leasing its 126 units before the grand opening in December. You can book a tour now.

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