The employees of the Building and Grounds Department voted Thursday to retain the Buildings and Grounds Maintenance Association (BGMA) as their bargaining agency.

The BGMA will ask the University to renew negotiations for a new contract this morning, Joseph A. Prebensen, president of the union, said Friday. The union is presently operating under its 1962 contract, though it officially expired in June.

Last week's 107 to 97 vote ended a factional dispute that has troubled the union since early July. At that time the skilled tradesmen of the union--mainly plumbers, electricians, pipefitters, and sheet-metal-workers--refused to join with other employees in negotiating a new contract.

Led by James W. Estabrook, the dissident minority formed the Mechanical Trades Employees Representative Association (MTERA), and petitioned the Massachusetts Labor Relations Board for the right to bargain separately with the University.

A central issue in the controversy was the system of wage differentials that has been in effect since 1962, when the BGMA was expanded to include all skilled and unskilled employees of the University. The skilled workers of the MTERA wished to retain the system. The BGMA faction favored re-institution of a flat wage rate for all trades.

Last week's vote probably means that the next BGMA contract will incorporate the flat-rate system. When contacted last Friday night, however, Prebensen declined to speculate on the details of the union's future proposals. "Our demands are not yet formulated," he said.

The next contract will not affect the unskilled groundsmen, who will negotiate independently with the University. The groundsmen remain, however, part of the BGMA. They were not permitted to vote in last week's election.