Robbinsville-based Sharbell Development Corp. started construction last week on two new buildings at the Plainsboro Village Center, in the Middlesex County township.

The buildings include a three-story, 30,000-square-foot medical office facility and an 18,000-square-foot mixed-use property with 6,000 square feet of ground floor retail and eight condominiums. Both properties are expected to be complete in 12 to 14 months, according to the developer.

“The plan for the community has always incorporated these two buildings,” said Sharbell principal Tom Troy.”It was just a question of waiting for the market to catch up.”

Plainsboro Village Center “which currently consists of eight buildings comprising 75,000 square feet of retail and office space, as well as 11 detached homes and 12 townhouses” is about 90 percent occupied, he said. The complex is anchored by the town’s new library, which was completed two months ago.

The medical office building is being driven by the new University Medical Center of Princeton at Plainsboro, which will be located about 1.5 miles away from the project and is slated to open in early 2012, Troy said.