The Zoning Board of Appeal on Tuesday approved a developer's plans to renovate a single-family home at 9 Fuller St. and add a rear extension with four floors - to create a total of 14 condos.

Anthony Monahan's plans call for three of the units to be sold as affordable, his attorney, Ryan Spitz, told the board.

Four of the units will have one bedroom, four two bedrooms and six three bedrooms, Spitz said.

He said the building would have 12 parking spaces in a garage under the extension, adding that an existing, smaller garage would be torn down to make way for the extension.

The project needed zoning variances because the building would be closer to its side and rear lot lines and would be too tall and have too many floors under the lot's zoning. Also, the building wouldn't have a loading dock as normally required for a multi-family building of that size.

Spitz said the project would help Boston meet its 2030 housing goals and newer zoning efforts calling for denser development near transit stations and lines - such as the Ashmont T station about a block away.

Through an aide, City Councilor Brian Worrell (Dorchester) supported the proposal. A neighborhood liaison with the mayor's office said a few neighbors had expressed concern about the loss of privacy with the building's proposed decks. Nobody spoke in opposition at the hearing.