Flexible warehousing startup Saltbox is growing its Seattle presence.

The company, which is headquartered in Atlanta, is doubling its space at 4786 First Ave. S. in Sodo Row with a 30,000-square-foot expansion slated to open on March 15. A Saltbox spokesperson referred to the expansion as a second location. The company opened a 31,000-square-foot space in the same warehouse complex in August.