Commonwealth Building

The Commonwealth Building is a 14-story commercial office tower in Portland, Oregon, United States, located at 421 SW 6th Avenue between Washington and Stark Streets. Designed by architect Pietro Belluschi, it was built between 1944 and 1948 and was originally known as the Equitable Building. It is noted as one of the first glass box towers ever built, pioneering many modern features and predating the more famous Lever House in Manhattan.


The building, which was built as the headquarters in Portland of the Equitable Savings and Loan Association, was originally intended to be 12 stories high but was later expanded to 14. It is constructed of sea-green glass and was the first to be sheathed in aluminum. It was also the first to use double-glazed window panels, and was the first to be completely sealed and fully air-conditioned.


The Commonwealth Building was added to the National Register of Historic Places (as the Equitable Building) in 1976.


In 1980, the American Society of Mechanical Engineers (ASME) designated the Commonwealth Building as a National Historic Mechanical Engineering Landmark. The ASME History & Heritage Committee bestowed this landmark status for the specific feature: the first large commercial building in the United States to pioneer the use of heat pumps for heating and cooling.

Building Activity

  • updated a digital reference
    about 5 years ago via Annotator
  • updated a digital reference
    about 5 years ago via OpenBuildings.com