The tilt-turn is the dominant and most recommended window style, now gaining popularity among discerning architects, designers and homeowners in North America. This versatile design is three windows in one: an inward opening casement in the turn position, a secure top-venting hopper in the tilt position and a tightly sealed picture window when closed.
In the tilt position, the window opens at the top with hinges at the bottom. In the turn position, the window is hinged on the side and opens by swinging inward. The uniqueness of this window is determined by the presence of another middle position, which opens at an angle of 45° providing a gap with a size between 10 and 13 millimetres at the top of the window. This is sufficient to ensure controlled ventilation of the room without heat loss.