Fidelity Investments will begin revamping its 750,000-square-foot Seaport World Trade Center office complex next year, consolidating a jumble of disjointed office and meeting rooms and adding new outdoor amenities and retail space.

The upgrades include new publicly-accessible plazas, expanded aprons on Commonwealth Pier and five programmed spaces on the Boston HarborWalk.

Fidelity’s real estate arm, Pembroke, will demolish five sections of the existing building’s perimeter to make way for the new outdoor amenities. Fidelity has occupied the property for over three decades through a long-term lease with Massport.

“It is essentially at the end of its life. It’s an inhospitable back office experience and we see enormous potential to revitalize the workforce experience, but also the waterfront experience,” Andrew Dankwerth, senior vice president at Pembroke, told Boston Planning and Development Authority (BPDA) directors at their monthly meeting Thursday.

The 132,000-square-foot exhibition hall space is being eliminated, while the office space component will increase from 502,000 to 636,000 square feet, and 33,000 square feet of retail space will be added, according to BPDA documents. Event space spread around the building will be consolidated and brought closer to the entrance on Seaport Boulevard, Dankwerth said.

As part of a community benefits agreement, Fidelity will pay $500,000 for construction of a new dock for water shuttles.

Construction is scheduled to run from 2020 to 2024.