A plaster frame for a luminaire includes a first attachment tab on a side of the plaster frame and a second attachment tab on the side of the plaster frame. The plaster frame further includes a back wall. The first attachment tab and the second attachment tab each include a rib protruding toward the back wall. The back wall and the first attachment tab define a first space for a hanger bar assembly to extend therethrough, and the back wall and the second attachment tab define a second space for the hanger bar assembly to extend therethrough.