The origin of the sliding sash window is something of a mystery, with various theories as to where the design originated from. Some speculate that it is a derivative of a simpler version that opened horizontally and is referred to as the ‘Yorkshire Sash'. Others argue that the horizontal sliding sash has its origins in Holland and some argue that actually, it is French. It seems that this may be so, as the word ‘sash' is actually a variation of the French word ‘chassis', which means frame. However, it has also been argues that the French version of the sash was not developed with counter-balancing; instead the sliding sash frame was held in place by a swivel block.
The earliest recorded account of a sash window is thought to be from W. Horman, within his 1589, Vulgaria. It states,
"Glasen window is let in the light...I have many pretty wyndowes shette with levys goynge up and down."
By the end of the 17th Century these windows were regularly used within English properties, with many famous examples, such as both Kensington Palace and Hampton Court Palace. It is thought that the earliest recording of a fully developed sash specification was taken by Sir Christopher Wren's master joiner, Thomas Kinward, while he was working at Whitehall Palace. Due to the royal approval, and the endorsement from Wren, wooden sliding sash windows became a status symbol throughout Britain and its (then) colonies. Used almost exclusively in new buildings, royal palaces and simple cottages, the sliding sash remained first-choice until the turn of this century.
With many advantages, the sash was also best suited to the British wet weather; closing the window vertically allows for good ventilation whilst limiting the amount of rain allowed in. Also, being contained within a box limits the chances of frame distortion and rot - offering a longer lifespan. Aesthetically, the sliding sash also adds an element of grace to a building - even when open.
The sash aesthetic was particularly suited to Georgian architecture, which whole heartedly embraced the design. It was then that the design was improved to allow for two moving panels of glass, rather than a fixed top panel. As glass manufacture improved, larger panes of glass were used and the classic Georgian ‘six over six' design was born.
By the Victorian era, box sash windows were widely used and decorated, inside and out, with lavish ornaments. The sash windows were now grouped in impressive bay designs and decorated with intricate moldings, leaded lights and latticework.
By the turn of that century sliding sash windows had become the most widely used window in Britain. However, since the First World War, their popularity has waned due to both their impracticality during the war (large panes of glass having to be taped up in order to avoid bomb blasts), and their high manufacturing costs post-war.
In recent years the sliding sash window has developed, with current techniques and materials improving the design. The charm of the sash window is a traditional part of our streets and town's aesthetic. Sash window specialists can now incorporate the current advances in window technology into the classic sash window aesthetic; improving energy efficiency, security and home comforts.