The Charleston Digital Corridor's Flagship3 development is headed toward final approval following a vote Wednesday by the city's Board of Architectual Review.

The board approved the conceptual designs of the four-story, mixed-use building planned for 999 Morrison Drive in downtown Charleston.

The newest flagship space would offer offices for startups similar to Flagship1 and FS2; it would also offer some longer-term space for more established, high-growth companies with up to 50 employees, according to Ernest Andrade, the Corridor's Executive Director.

Andrade expects the project to be fully financed by local tech entrepreneurs and tech companies and that construction will begin this fall.

Flagship3 will be around 45,000 square feet, more than twice the combined size of Flagships and FS2, along Calhoun and Alexander streets.

Rush Dixon of Rush Dixon Architect presented the design plans for the Flagship3 to the board. Dixon pointed out design changes based on the board's prior recommendations, including a more simplified roof layout and elements more similar to Charleston's architecture and style.

For the entryway, Dixon took inspiration from unique corner entrances on buildings around Charleston. He also worked to include designs that emulate "technology and energy in motion."

Rush Dixon representatives will take the board's comments and make further revisions before going back to the board for preliminary and final approvals. The Digital Corridor is also working on the design for the parking garage as well as financing for the project.

The Flagship3 and an adjoining parking lot will be the anchor tenant for the city of Charleston's planned 10-acre Charleston Innovation District along Morrison Drive. The city and the corridor want to create a place for tech companies and startups to cluster in high-density, mixed-use developments.

The tech district includes 999 and 995 Morrison Drive. Charleston County owns 995 Morrison Drive and houses administrative buildings there.

Charleston City Council voted unanimously in July to allow buildings up to 85 feet in the tech overlay district. This vote increased the previous height restriction of 55 feet to accommodate the 76-foot tall Flagship3.

The city is also working on a new master plan for about 860 acres north of the Arthur Ravenel Jr. Bridge to accommodate a growing population. In addition to the tech district, plans call for a mix of housing options at different price points, mixed-use developments, office space, public transit, more bike lanes and parks.

Andrade said the city's passage of the tech overlay district and height allowance show "a public-private partnership at its best."

"There is a lot of work ahead, but today, the BAR affirmed that we will lead the creation of a 21st-century district of 'modern architecture' to complement the city's historic core while accelerating Charleston's high-wage, tech community," Ernest said in an email after the meeting.