Children's of Alabama plans to move forward with the construction of a 12-story parking deck and six-story office building on 4th Avenue South.

The conceptual design of the structures was approved Wednesday morning by the city of Birmingham's Design Review Committee. The committee also approved the hospital starting site work and construction of the foundations.

Children's of Alabama must go back to the Design Review Committee in early 2018 to receive final approvals.

Demolition of an existing hospital warehouse on the property located between 16th and 17th streets has started, a hospital spokesperson confirmed.

Construction on the $54 million project isn't slated to start until January 2018 and conclude in spring 2019.

Children's of Alabama first announced plans for the project in July.

The new office building will house non-clinical support services, many of which have been located outside of the main campus since construction began on the Benjamin Russell Hospital for Children building in 2008, according to the hospital.

The parking deck will add 1,500 parking spaces. It will be constructed on an existing surface parking lot used by Children's employees.

The deck will be constructed before the 115,000-square-foot office building.

About 200 offsite workers will move to the main campus when the project is complete.

"This project will help to relieve parking congestion on our campus," Mike McDevitt, Children's Vice President for Facilities, said in July. "By adding this much-needed parking for staff, we can also dedicate space closer to the hospital itself for our patients' families and visitors. There are many days, especially during cold and flu season, when our current parking is, quite frankly, inadequate."

Brasfield & Gorrie is the general contractor. Williams Blackstock Architects is the project's architect.

The parking deck and office building will be connected by a pedestrian bridge across 4th Avenue South to Children's existing Park Place building. It'll connect all of Children's Russell Campus facilities.