Google is expanding in South Lake Union again.

The tech company is set to take over the new 12-story, 322K SF office tower planned at Mercer Street and Westlake Avenue in South Lake Union, the Seattle Times reports.

Vulcan Real Estate is building the project, which is directly across the street from a Google office development that is under construction. Vulcan is also constructing that four-building, 607K SF Google office campus. The campus is set to be complete in early 2019.

Construction costs on the newest project are expected to be $88.5M and will replace a block of three buildings that include Guitar Center, Uptown Espresso and the Clements Rice office building. It should be complete in 2021.

Once the new tower is complete, Google will occupy nearly 1M SF of office space in South Lake Union.

Google currently has 3,000 employees in the greater Seattle area, including Fremont and Kirkland. The new buildings will give the company room to grow the number of employees to between 4,800 to 6,300.