Who Invented The Sash Window And What Is Its Origins - A Complex Tale

It is impossible to tell who invented the sash window and what is its origins. In French, a 'chassis' means a frame and sash derives from this word. They may have been created in Holland, as the window is in some Vermeer paintings. A 'Yorkshire Sash', a sash window that slid along the horizontal axis was used in England at around the same time.

Research shows that the French may have used the horizontal sash window and later replaced this with a vertical sash. A block which swiveled and held the window open was replaced by the rope and sash weight as mechanical solutions appeared. Britain colonized many countries at this time and took away with the the architectural, cultural and artist creations they found. The Queen may have appropriated the French craftsmen as well.

Robert Hooke used them in Ham House in 1670 and by the end of the 17th century they were in Hampton Court and Kensington Palace. However, Thomas Kinwood, master craftsman to Sir Christopher Wren, is credited with the first known plan of the window, installed at the Whitehall Palace. As Wren was an influential architect and a royal favourite, he made these windows fashionable. They became a feature of both cottages and palaces in Britain and its colonies.

In a rainy climate, the window is ideal allowing for ventilation while protecting from rain through leaving a narrower gap at the bottom or top of the window. Casement windows with their hinges rotted and warped in the weather. The sash had a frame to enclose its mechanical parts. They are also more beautiful on the front of a building with larger panes and fewer wooden joins.

Originally sashes only had a lower section that opened. During the Georgian period when their use became ubiquitous, both windows were designed to move. Oak was most commonly used for the frame. As glass manufacture became more efficient, larger panes needed less wood to support them. The classic design of six panes over six, comes from this period.

The Victorians loved sash windows and embellished them with varied ornamentation. Grouped in bays, they were surrounded by fancy stone work. Ground floor rooms had larger windows for more light. Upper stories had smaller windows to increase the sense of perspective and grandeur.

Casement windows, widely used until the early 1600's were replaced by sash windows until the early 1920's. A sash window was preferred and reigned supreme. After the First World War, master craftsmen were less affordable. Casement windows were again easier to mass produce in wood or metal in factories. Who invented the sash window and what is its origins remains lost in the distant past.