Developer proposes turning Portland Street office building into 25 apartments

A developer has filed plans with the Boston Planning Department to convert what is now a vacant six-story office building at 129 Portland St. into 25 apartments and ground-floor retail space, under the city's office-to-residential tax-abatement pilot.

Charlestown developer Greg McCarthy has an agreement to buy the building and then convert it into residential units under the city pilot, which offers a 29-year break on property tax for the building, through an abatement of up to 75% of the building's assessed value. Boston currently assesses at $8.6 million.

Last month, McCarthy proposed a similar conversion of a one-time BU Medical Center office building on Albany Street in the South End into 24 residential units.

Under McCarthy's plans for the Portland Street building, which dates to the 1890s, units would range in size from studios to three bedrooms. Four of the units would be rented as affordable, another would be made available to tenants with a Section 8 housing voucher.

His filing estimates conversion costs of $4 million.

129 Portland is a brick structure in excellent condition. The exterior needs little to no work. The majority of the project will include restoration of the existing facades with little to no changes from the current configuration.

129 Portland St. filings.