Image courtesy The Davis Cos.

A Boston developer is proposing an expansion nearly doubling the size of the 88 Black Falcon property in an early test of plans to allow more non-industrial uses within the Raymond L. Flynn Marine Park.

The Davis Cos. proposes a 4-story, 330,600-square-foot addition to the nearly 354,000-square-foot complex including a mix of office, R&D, lab and marine industrial tenants.

The Davis Cos. acquired the ground lease for the property, which is owned by Massport, in 2017 for $60 million. Under state Chapter 91 regulations, 75 percent of the building’s space is reserved for marine industrial uses.

But Boston officials have proposed changes to the zoning for the 191-acre marine park reflecting declining demand for industrial space, as office, lab and residential projects have spread across the Seaport District in the past decade.

The state Executive Office of Environmental Affairs is reviewing proposed zoning changes allowing more non-industrial uses on the upper floors of buildings in the marine park, which includes industrial buildings that were once part of the South Boston Naval Annex.

The project would add 174 parking spaces and could include improvements to the intersection of Drydock and Black Falcon avenues and pedestrian access, according to a notification letter submitted to the Boston Planning and Development Agency.