STONE

Multnomah County Central Courthouse

Complete insulated aluminum wall system

Multnomah County Central Courthouse

Portland, OR

©multco.us

Architect: SRG Partnership

Completion: 2020
Category: Institutional 

Project Type: Stone Engineering

Video

Jan 2017–Construction Sequence

Webinars

Sep 20—Stone Cladding Technologies

Jan 2021–Masonry: Let’s Get Creative

When the existing central courthouse was built in downtown Portland between 1909 and 1914, Multnomah County had one-third its current population. This was long before modern building code standards for earthquakes were in place. A century’s worth of public use combined with increased demands from today’s much larger population of more than 800,000 county residents created major functional difficulties and serious safety problems that had to be resolved. The courthouse is an essential home for the community's daily judicial operations and must be functional even in the case of a major catastrophe like an earthquake. The courthouse is one of the few community spaces that the public is compelled to enter—for activities ranging from jury duty to fulfilling legal obligations by paying a parking ticket or serving as a trial witness. In addition, the state of Oregon requires the county to provide facilities for the courts to operate.

The Architect’s design of this 17-storey building consists of strip of glass curtainwall and stone. Although flat—it strip staggers up the elevation and there was consideration to provide “curtainwall-like” stone wall. The challenges PICCO faced were the seismic 3" storey drift, and solving how to design a flexible enough facade system to accommodate storey drift, yet strong enough to support the stone, and also ensuring that system is a water-tight rainscreen wall—after a seismic event.

A mock-up was created for ASTM testing, a 15-minute water penetration test,  inter-story differential horizontal movement tests (no failure of anchors, frame, glass or panels was observed), and seismic movement displacement test to test the cladding.