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Last edited 07 Apr 2021
Types of window
Windows are openings fitted with glass to admit light and allow people to see out. They are often openable to allow ventilation. Although the historic use of glass dates back to the Romans, glass windows only became common domestically in England in the early-17th century, gradually becoming more versatile and widespread as plate glass processes were perfected during the Industrial Age.
- Annealed glass.
- Fire-resistant glass.
- Float glass.
- Fully tempered glass.
- Glass brick.
- Heat soaked tempered glass.
- Heat strengthened glass.
- Insulated glazing units.
- Laminated glass.
- Low-emissivity glass (Low-E glass).
- Self-cleaning glass.
- Stained glass.
- Toughened glass.
- Wired glass.
- Bay: Multi-panel windows that project in front of the external wall line, supported by a sill height wall.
- Bow: A curved bay window.
- Bullseye: A circular window.
- Clerestory: Bands of windows across the tops of buildings that allow natural light in without compromising privacy or security.
- Curtain wall: A non-structural cladding systems generally associated with large, multi-storey buildings.
- Display window: Intended for the display of products or services on sale within a building.
- Dormer: A small roofed structure that projects outwards from the main pitched roof of a building.
- Glass mullion system: Sheets of tempered glass held in position by clamps and joined by a structural silicone sealant or by metal patch plates
- Multi-lite: Windows glazed with small panes of glass separated by glazing bars, or muntins.
- Patent glazing: A non-load bearing, two-edge support cladding system.
- Picture window: A large fixed window that lets in the maximum amount of light and provides external views.
- Roof window: A window that is in the same plane as the surrounding roof, and has a minimum pitch of 15 degrees.
- Rooflight / skylight: A dome light, lantern light, skylight, ridge light of glazed barrel vault installed on an upstand, so it is not in the same plane as the surrounding roof.
- Sidelight: Positioned beside a door or main window.
- Toplight: These are usually above doors.
- Transom window: A horizontal window that is commonly mounted above a door or another window to let in more light.
 Method of opening
- Awning: Hinged at the top and opened outwards.
- Bi-fold: Made up of a number of individual sashes, usually 2, 3 or 4, hinged together.
- Casement: An opening window fixed to the frame by hinges along one of its edges.
- Fixed light: A window that is fixed in place and cannot be opened.
- Louvre: A series of parallel pieces of glazing that are hung on central pivots.
- Pivot: Hung on one hinge at centre points on each of two opposite sides allowing the window to revolve when opened.
- Sidehung: A variation on a casement window, side opening controlled by tracks and slides.
- Tilt and slide: Tilts inwards at the top and slides horizontally behind the fixed pane.
- Tilt and turn: Include a mechanism that allows them to tilt inwards from one edge or to open inwards from one side.
- Topguided: Tracks and slides enable the top to slide downwards whist the bottom opens out.
- Vertical slider / sash: Glass is fitted in ‘sashes’ (moveable panels) that slide vertically past each other.
The Window Energy Ratings (WER) is a scale developed by the British Fenestration Ratings Council (BFRC) to measure the thermal performance of windows. The BFRC label indicates the rating of the window on a scale running from A+ (the most energy efficient) to G (the least efficient).
See: Architectural styles.
 Related articles on Designing Buildings Wiki.
- Angular selective shading systems.
- Architectural styles.
- Bespoke window.
- Bay window.
- Birds and building collisions.
- Bullseye window.
- Crittall metal windows.
- Domestic windows.
- Double glazing.
- Double glazing v triple glazing.
- Easily accessible window.
- Glass manifestation.
- Historic steel-framed windows.
- Light well.
- Louvre (or louver).
- Sash windows.
- Security glazing.
- Stained glass.
- Triple glazing.
- Types of blinds.
- Types of door.
- Window and door schedules.
- Window Energy Rating.
- Window frame.
- Window parts.
- Yorkshire Lights.
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