A proposed bylaw that would make mixed-use buildings legal in Bridgewater’s downtown area for the first time in many years has been approved by the Planning Board and sent to the Town Council for consideration, Town Planner Greg Guimond said. Although grandfathered apartments exist over businesses, reconstruction of buildings beyond repair could be only one story tall under current policy, he said. The proposal would allow five to eight residential units per acre, by special permit, in a mixed-use project. The higher number would be allowed if some units are designated as affordable housing, according to the planner. He said the town’s master plan called for the change about 10 years ago, but it has not been made, and that the bylaw could encourage reinvestment in downtown buildings. The Planning Board voted to approve the proposal on March 18.