The Zoning Board of Appeals has approved the Parc at Medfield apartment development by a vote of 2 to 1, but without deciding on its final conditions for the project. The conditions, which may include a reduction in the number of apartments, from 96 to 94, are slated to be resolved during the board’s 4 p.m. meeting Monday. The complex is being proposed by the Gatehouse Group under the state’s Chapter 40B affordable-housing law, which allows developers to bypass certain local zoning rules in communities like Medfield, where less than 10 percent of the housing stock is considered by the state to be affordable. Medfield’s figure is 4 percent. Under the law, Gatehouse must rent a percentage of the units at below-market rates to income-eligible tenants. The zoning board voted to approve the project, slated for a West Street site near Route 27, at its Dec. 6 meeting. The dissenting vote was cast by board chairman Robert Sylvia, who resigned after the hearing in protest of the project’s approval.