What is a horizontal pivot window?
A horizontal pivot window is a window whose sash rotates about a horizontal axis located at roughly half the height of the window. When opened, one half of the sash swings inwards and the other half outwards, usually the top inwards and the bottom outwards. In Dutch it is called a ‘tuimelraam’, a tumbling window.
How it works
The pivots are fitted at the left and right of the frame, on the axis of the sash. Because the weight above and below the axis is roughly balanced, the window turns easily. Many versions can rotate far enough for the outer face of the glass to face the room. A friction brake or stay in the hardware holds the sash in the chosen position.
Pivot window or another type?
- Top-hung window: hinged at the top, opens outwards.
- Hopper window: hinged at the bottom, tilts inwards.
- Vertical pivot window: rotates about a vertical axis, so it swings sideways.
- Horizontal pivot window: rotates about a horizontal axis in the middle.
Application
- Ventilation: an opening forms at both top and bottom, so warm air escapes at the top while cooler air enters below.
- Tall or large windows in commercial buildings and high-rise, where the glass must be cleaned from the inside.
- Roof windows: many roof windows work on the same principle with a centre pivot.
Tips and points of attention
- Room inside: the top half swings into the room. Mind curtains, blinds, window sills and plants.
- Weather seals: the rebate is on one side above the axis and on the other side below it. When repairing or replacing, the seals must close properly in both halves.
- Safety: on upper floors, a restrictor or child safety catch is sensible for windows that rotate far.
- Look after the hardware: lubricate the pivots now and then and check the brake; a slack brake lets the sash slam shut in the wind.
Related terms
- Vertical pivot window
- Hopper window
- Tilt and turn window
- Pivot hinge
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