Sash carriers mounted to the sides of a sash support the sash in a window frame for sliding movement between sliding closed and sliding open positions. Balance springs on the sash carriers counterbalance the weight of the sash during the sliding movement. The sash can be mounted to the sash carriers for tilting movement between tilt closed and tilt open positions. Brakes on the sash carriers are actuated by the sash when the sash is moved to the tilt open position, and inhibit sliding movement of the sash carriers and sash when the sash is in the tilt open position.