Abstract: A tilt window includes a frame with a sill, a header and a pair of jambs, each extruded from rigid plastic material. Each member is formed of multi-hollow construction for overall strength and rigidity. The jamb comprises, in cross-section, a base and an inner leg, an outer leg and center leg projecting from the base to form inner and outer channels. A portion of each center leg and outer leg projects to form a sash engagement panel. The sashes are held within the respective channels by sliding balance shoes and latch members, and may be tilted inwardly away from the sash engagement panels for cleaning.