word 'sash' is derived from the French word 'chassis',
meaning frame. However there is little evidence of it
being a French innovation.
French term became commonplace is unknown but it is one
of many English words in common use that have been
derived from the French. Nowadays the trend is in the
opposite direction, much to their annoyance.
innovation in the sash window was the use of a counter
balancing weight. Sash windows without counter balancing
were produced way before the 17th Century. They were
originally designed to operate horizontally and then
later in the vertical, as now, but they would have been
heavy to open and were held in place with wedges and
counter balancing idea has not been historically traced
but they were well in evidence towards the end of the 17th
Century in great houses like Chatsworth and Kensington
Christopher Wren was an ardent fan of the sash window,
he was doubtless impressed by its simple but effective
principle and they soon became a distinctive feature of
Georgian and later Victorian buildings, great and small.
Traditionally made from hard woods such as oak, the
design enabled the user to open the window as much or as
little as they wished, and in a country prone to wind
they had the added advantage of not jutting out like
sails catching the wind when opened.
the cost of labour rose, quick to fit, mass produced
windows came to the fore, but the skills of the sash
window maker are still in demand and there will always
be a craftsman somewhere who gets a special thrill from
making one of the few remaining mechanical devices made